Search the FAQ Archives

3 - A - B - C - D - E - F - G - H - I - J - K - L - M
N - O - P - Q - R - S - T - U - V - W - X - Y - Z
faqs.org - Internet FAQ Archives

8051 microcontroller FAQ


[ Usenet FAQs | Web FAQs | Documents | RFC Index | Business Photos and Profiles ]
Archive-name: microcontroller-faq/8051
Posting-Frequency: monthly
Last-modified: September 11, 1997

See reader questions & answers on this topic! - Help others by sharing your knowledge
This article is a collection of information sources on the Intel 8051
family of microcontrollers (and variants).

The following topics are addressed:

      0)  Rantings and ravings (to make the FAQ zero-based)

      1)  ABOUT THIS FAQ
    1.1)  Who put this FAQ together?
    1.2)  How can I contribute to this FAQ?
    1.3)  What newsgroups will this FAQ be posted to?
    1.4)  May I distribute this FAQ or post it somewhere else?
    1.5)  How about FAQs on other microcontrollers?

      2)  ABOUT THE 8051
    2.1)  The 8051 microcontroller
    2.2)  8051 Flavors
    2.3)  16-bit 8051 parts
    2.4)  8051 representatives and approximate prices
    2.5)  Common and New 80x51 variants
    2.6)  Advantages realized in implementing control applications on
          this family of microcontrollers
    2.7)  Getting started
    2.8)  Technical Questions and Answers

      3)  SOURCES OF INFORMATION ON THE 8051
    3.1)  FTP sites
    3.2)  Web pages
    3.3)  Mailing lists
    3.4)  BBSs
    3.5)  Help available!

      4)  8051 PRODUCTS
    4.1)  Free languages and development tools
    4.2)  Free C compilers
    4.3)  Commercially available products

      5)  8051 DOCUMENTATION
    5.1)  Periodicals
    5.2)  Books
    5.3)  Miscellaneous documentation


0)  Rantings and ravings

    Disclaimer:  Just so it is understood, the "rantings and ravings" are
    my rantings and raving.  My readers are refined and sophisticated and
    would never rant or rave.  I, on the other hand, sit in front of the
    TV in torn underwear and drink beer out of the bottle.

    =====> OK, I know this FAQ is long. Very long. Well... it's
    ridiculously long. If you are inconvenienced or strenuously object to
    the posting of this FAQ, please DON'T FLAME me or send me nasty mail.
    Just think what I have to go through. This FAQ takes a lot of my
    time, of which I have very little to spare. I'm open for suggestions.
    I've considered the following:
        - splitting it up into smaller parts
        - eliminating certain sections which may no longer be relevant -
          the web and search engines certainly seem to make a lot of this
          FAQ obsolete (or am I mistaken on this?)
        - not posting it to the newsgroups and just turning this
          whole mess into a [large] web page (the problem with this
          is that I don't have a web site)
        - forgetting about it all together and reminding my kids that I'm
          their father (if you all tell me to go packing, I'll gladly
          fold up shop and devote more time to family, friends, and
          personal hygiene)
    I would be happy to hear ideas on how this FAQ could be improved for
    the reader. If it makes MY job easier, then that's even better.


    OK, with that out of the way, let's get on with it...


    Well, it's finally here. A free C compiler for the 8051. Featured in
    Dr. Dobb's August 1997 issue, Andy Yuen's Retargetable Concurrent
    Small C (RCSC) is based on James E. Hendrix' lengendary Small C. A
    previous iteration of RCSC, Concurrent Small C was introduced in the
    August 1996 issue of Dr. Dobbs. With the release of this compiler,
    Andy Yuen is very likely to become a folk hero.

    So, why are you still reading this? The FAQ will wait! First download
    a copy of RCSC. You can get it from: http://www.ddj.com or
    ftp://ftp.mv.com/pub/. Then go out and find a copy of Dr. Dobb's
    August 1997 issue.

    You'll still need to purchase either James E. Hendrix's "A Small C
    Compiler" (ISBN 0-13-814724-8) or the Dr. Dobb's Small C Compiler
    Resource CD. This of course means that the free C compiler isn't
    totally free, but then again, what is?


    If you'd like to start learning about microcontrollers, but the
    thought of finding all the parts and then building one scares you,
    take a look at the line of boards available from American Educational
    Systems. They have three boards: AES-51 (8051), AES-11 (68hc11), and
    AES-88 (8088). All three boards are built along the same lines and
    include RAM, ROM, LCD display, keypad, A/D, serial ports, digital I/O
    ports, and logic probe. Also included is a full bookshelf of
    documentation. The AES-51 comes with a hardware manual, language
    manual, and Intel's 8051 User's Manual (over 500 pages of reference
    material). The board has a built in BASIC-52 and monitor built into
    external ROM on board. The BASIC even includes commands for
    displaying on the LCD. These boards are ridiculously easy to use and
    program - you can get started experimenting right away.

    This is a perfect system for students and hobbyists. Even
    professionals will find this system useful as a prototyping tool and
    test bed. Highly recommended.

    For more information, contact:
          American Educational Systems
          970 West 17th St.
          Santa Ana, CA  92706  USA
          (800)730-3232 or (714)550-8094   Fax: (714)550-9941


    SPJ Systems (Pune, India) has announced version 3.0 of their C
    compiler for the 8051.  The major new feature of this version is
    support for the "bit" type.  Although this version imposes some
    limitations on the use of this newly supported type, you can now use
    the bit manipulation capability of the 8051.  One important benefit
    will be smaller code size and code which is easier to maintain and
    understand.

    A working demo of the compiler package, which includes the library
    sources and permits the compilation of small programs, is available
    from their web site.

    For questions or comments about the product, you can contact them at:
          SPJ SYSTEMS
          114, Chitrashala Bldg.
          562, Sadashiv Peth
          Pune, India
          Phone: 91-212-451607   Fax: 91-212-480285
          Email: spjs@giaspn01.vsnl.net.in
          Web:   http://www.prime-digest.w1.com/spj


    Air Born Electronics in Australia has some nice project plans for the
    8051 available on their web site. Point your browser at:
         http://www.airborn.com.au/


    MDL Labs offers the following BASIC language packages for the 8051:
         1. BASIKIT--Integrated Programming Environment for BASIC-52
            and for MDL-BASIC-I, MDL-BASIC-P, and MDL-BASIC-D. BASIKIT
            includes a full-screen editor and permits writing programs
            with labels rather than line numbers.
         2. MDL-BASIC-I and MDL-BASIC-P are supersets of the original
            BASIC-52, for the Intel 8052 and the Phillips PCB83C552,
            respectively. All bugs removed.
         3. MDL-BASIC-D is a BASIC for the Dallas 87C530 which accesses
            all the features of the chip, including both serial ports,
            the Watchdog, and the power-saving features. The BASIC will
            address up to 512K of memory and will collect data into that
            memory via serial port interrupts. It runs faster at 25 MHz
            than compiled code on the 8052.
         MDL Labs
         1073 Limberlost Court
         Columbus, OH 43235
         Tel/Fax: 614-431-2675
         Email: arl@infinet.com


    Students at the Universidade Federal de Santa Catarina, Brazil
    developed a "Remote Lab for the 8051". You send a machine code of the
    8051 to a remote host (where there is 8051 board plugged in the PC)
    and receive the values of the registers. Study the 8051
    microcontroller, without buying a board. For more information:
          www.inf.ufsc.br/~jbosco/labvir.htm
    The Email of students are:
          Miguel <wf@ambiente.com.br>
          Cleber <cleber@inf.ufsc.br>


    Hans Schou write to inform that the USB organization now has their
    own homepage: http://www.usb.org (was http://www.teleport.com/~usb).
    Hans is also willing to help out with problems using the 8051. His
    new email address is: chlor@schou.dk


    TCG (in Taiwan) has introduced two new products. One product is
    32K-byte EPROM Emulator and the other is AT89C2051/1051 programmer
    with limited emulation capability. These products feature platform
    independence. You can use PC, Mac, Unix workstation, or even a dumb
    terminal. All the necessary commands are built into the on-board
    controller. For more information, check out these web sites:
         http://www.yp.at-taiwan.com/~com00121
         http://www.hth.com
    For more information:
         TCG
         11 Ally22 Ln21 Pei-Ta Rd., Hsin-Chu City, Taiwan, R.O.C.
         (886)3-532-7372   Fax: 886-3-531-7162
         Email:ch.bbs@csie.nctu.edu.tw


    Take care,

              Uncle Russ


1)  ABOUT THIS FAQ

1.1)  Who put this FAQ together?

    I was prompted to put this FAQ together in response to my own
    frustration in searching for information, and to the constant
    occurrence of requests for information on this subject in various
    newsgroups.  Hopefully others won't need to go through what I did.

    Normally, I spend all day programming in assembler or C on an IBM PC.
    With my hobbyist hat on I decided to try my hand at a little
    microcontroller project design.  When it came time to start, I had no
    idea what to do.  I had nothing to start with - no assembler, no
    programming language, no simulator.  I cobbled together a simulator
    to help me learn about the workings of the chip.  It's not being made
    available to the public since I'm afraid the simulator isn't very
    good.  It was for my own use, so the user interface (there is none)
    really sucks eggs.

    I decided to search the net for information on the 8051.  This list
    was compiled the hard way, logging onto every anonymous ftp site I
    could find and looking around.  I also used Archie, other FAQs and
    lists, and every reference to the 8051 that appeared in the various
    news groups.  It took a long time till stuff finally started popping
    up.  I saved all of my notes and the result was the first version of
    this FAQ.  Responses have been pouring in, and the result is a much
    more complete and thorough FAQ.


1.2)  How can I contribute to this list?

    I please ask that if you have any suggestions or additions, or you
    would like to correct any of the information contained herein, please
    send me a note.
         My Email address is:  russ@shani.net
         My Snail-Mail address is:
               Russ Hersch
               HaVradim 11
               Ginot Shomron
               ISRAEL

    The list of individuals who have sent suggestions and encouragement
    is endless.  I hope it suffices to say "Thank you to all who have
    contributed to this FAQ - we all appreciate it."

    Special thanks to recent contributors:
          Pramod Ramade (SPJ Systems)
          Mark Meyer (American Educational Systems)
          Michael Markowitz (EDN magazine)
          Enrique Viseras
          Philippe Techer (Virtual Micro Design)
          Richard Lane
          Ray Lavender (MDL Labs)
          Hans Schou
          Alfred Arnold
          CH Tsai (TCG, Taiwan)

    I hope that those of you who know of interesting items for the 8051
    will share with everyone by contributing to this list.  Piles of
    stuff is turning up thanks to everyone's help.

    If you are a manufacturer and have a web site, ftp site, or BBS
    available that supports the 8051, please let me know by EMail so that
    I can add it to this FAQ.  Also, please feel free to update me on new
    products.


1.3)  What newsgroups will this FAQ be posted to?

    This FAQ will be posted to the following newsgroups:
          comp.sys.intel
          comp.realtime
          comp.robotics
          comp.lang.forth
          sci.electronics
    These newsgroups often contain discussions, announcements, or
    information on the 8051.  Check them out from time to time.

    The schedule for posting will be once a month.  I can't promise that
    it will be on time, but I hope to post it on the 26th of each month.

    You might also want to check out the following newsgroups, since they
    quite frequently have discussions about the 8051 and other
    microcontrollers:
          comp.arch.embedded
          alt.comp.hardware.homebuilt

    A bit farther afield, but still of possible interest:
          comp.lang.misc
          comp.ai.fuzzy
          comp.dsp
          sci.engr.control
          sci.engr.semiconductors


1.4)  May I post this FAQ to my local BBS?

    I am putting no restrictions on the use of this FAQ except - It must
    be distributed in its entirety with the copyright notice, and no
    financial gain may be realized from it.  After all, I have spent, and
    continue to spend, a lot of time on this.  The only thing that I
    intend to gain from it is more information on the 8051, and getting
    to know my fellow 8051 groupies better.

    For this reason I have appended a copyright statement to the end of
    this FAQ.  I feel pretty silly doing this, but I just want to protect
    myself.  The copyright does not limit the use of this list for
    noncommercial purposes.  I hereby give my permission to one and all
    to pass this list around and post it wherever you want - as long as
    it is not for financial gain.

        Thank you.


1.5)  How about FAQs on other microcontrollers?

    If anyone wishes to start a FAQ on another microcontroller, please
    feel free to copy the format of this FAQ - I don't intend on
    copyrighting the look and feel ;-).  With a common format, we will
    all benefit when trying to find information on a particular
    microcontroller.


    Other Microcontroller FAQs

      Subject:  PIC microcontrollers
      Newsgroups:  <no longer posted to newsgroups>
      Web page:  http://digiserve.com/takdesign
      Maintainer:  Tom Kellett
                   Email: Tom@takdsign.demon.co.uk

      Subject:  68hc11 microcontrollers
      Newsgroups:  comp.realtime
                   comp.robotics
                   sci.electronics
      Archive:  rtfm.mit.edu :  <plus all mirror sites>
                /pub/usenet/comp.answers/microcontroller-faq/68hc11
                /pub/usenet/sci.answers/microcontroller-faq/68hc11
                /pub/usenet/news.answers/microcontroller-faq/68hc11
      Maintainer:  Robert Boys - Ontario, Canada
                   Email: rboys@best.com
                   Russ Hersch (maintainer emeritus :-)

      Subject:  Microcontroller primer and FAQ
      Newsgroups:  comp.sys.intel
                   comp.arch.embedded
                   comp.robotics
                   sci.electronics
                   alt.comp.hardware.homebuilt
      Archive:  rtfm.mit.edu :  <plus all mirror sites>
                /pub/usenet/comp.answers/microcontroller-faq/primer
                /pub/usenet/sci.answers/microcontroller-faq/primer
                /pub/usenet/news.answers/microcontroller-faq/primer
      Maintainer:  Russ Hersch
                   Email: russ@shani.net


    Additional FAQs of interest

      Subject:  I2C protocol
      Newsgroups:  sci.electronics
                   alt.hardware.homebuilt
                   comp.robotics
                   comp.protocols.misc.
      Comments:    The I2C bus is a simple 2 wire serial interface
                   developed by Philips.  A number of 8051 variants as
                   well as several peripherals include I2C support.
      Maintainer:  Vincent Himpe
                   Email: Vincent.Himpe@ping.be

      Subject:  Robotics
      Newsgroups:  comp.robotics
      Maintainer:  Kevin Dowling
                   (412)268-8830
                   Email: nivek@ri.cmu.edu
                   Smail: Carnegie Mellon University
                          The Robotics Institute
                          Pittsburgh, PA 15213

      Subject:  Electronics
      Newsgroups:  sci.electronics
      Comments:  There are a number of FAQs available in this newsgroup
                 on various subjects.  Among some of the subjects covered
                 are:  LCDs, stepper motors, etc.

      FAQ subject:  Real-time
      Newsgroups:  comp.realtime, comp.answers, news.answers
      Archive:  rtfm.mit.edu : pub/usenet/comp.realtime
      Maintainer:  Mark Linimon
                       Lonesome Dove Computing Services
                       Roanoke, Virginia
                   Email: linimon@nominil.lonesome.com.

      Subject:  Motorola 68K microprocessor line
      Newsgroups:  comp.sys.m68k
      Comments:  without a doubt, one of the finest FAQs ever written
                 (well, of course Bob paid me to say this ;-)
      Archive:  bode.ee.ualberta.ca : pub/motorola/general
                ftp.luth.se : /pub/misc/motorola/faq
                file name of archive is m68kfaq?.zip (? is version)
      Maintainer:  Robert Boys - Ontario, Canada
                   Email: rboys@best.com


    For more detailed information on various 8051 microcontroller parts,
    see the article posted to comp.robotics and sci.electronics which
    provides a tabular cross reference of features and pin counts on a
    wide range of microcontrollers (including the 8051 family).  This
    list was compiled and is being maintained by Roger Nelson
    <rnelson@wsuaix.csc.wsu.edu>.

    For more information on various microcontrollers and their features,
    refer to the Microcontroller primer and FAQ listed above.


2)  ABOUT THE 8051


2.1)  The 8051 microcontroller

    The 8051 is an 8 bit microcontroller originally developed by Intel in
    1980.  It is the world's most popular microcontroller core, made by
    many independent manufacturers (truly multi-sourced).  There were 126
    million 8051s (and variants) shipped in 1993!!

    A typical 8051 contains:
       - CPU with boolean processor
       - 5 or 6 interrupts: 2 are external
                            2 priority levels
       - 2 or 3 16-bit timer/counters
       - programmable full-duplex serial port
         (baud rate provided by one of the timers)
       - 32 I/O lines (four 8-bit ports)
       - RAM
       - ROM/EPROM in some models

    The 8051 architecture is a tad bizarre, but then so are the
    architectures of most microcontrollers due to their specialization
    (check out the PIC for creativity - for that matter, take a look at
    any RISC chip).  One vexing problem with the 8051 is its very
    non-orthogonal instruction set - especially the restrictions on
    accessing the different address spaces.  However, after some time
    programming the chip, you can get used to it - maybe even appreciate
    it.

    One strong point of the 8051 is the way it handles interrupts.
    Vectoring to fixed 8-byte areas is convenient and efficient.  Most
    interrupt routines are very short (or at least they should be), and
    generally can fit into the 8-byte area.  Of course if your interrupt
    routine is longer, you can still jump to the appropriate routine from
    within the 8 byte interrupt region.

    The 8051 instruction set is optimized for the one-bit operations so
    often desired in real-world, real-time control applications.  The
    boolean processor provides direct support for bit manipulation.  This
    leads to more efficient programs that need to deal with binary input
    and output conditions inherent in digital-control problems.  Bit
    addressing can be used for test pin monitoring or program control
    flags.


2.2)  8051 Flavors

    The 8051 has the widest range of variants of any embedded controller
    on the market.  The smallest device is the Atmel 89c1051, a 20 Pin
    FLASH variant with 2 timers, UART, 20mA.  The fastest parts are from
    Dallas, with performance close to 10 MIPS!  The most powerful chip is
    the Siemens 80C517A, with 32 Bit ALU, 2 UARTS, 2K RAM, PLCC84
    package, 8 x 16 Bit PWMs, and other features.

    Among the major manufacturers are:
        AMD      Enhanced 8051 parts (no longer producing 80x51 parts)
        Atmel    FLASH and semi-custom parts
        Dallas   Battery backed, program download, and fastest variants
        Intel    8051 through 80c51gb / 80c51sl
        ISSI     IS80C51/31 runs up to 40MHz
        Matra    80c154, low voltage static variants
        OKI      80c154, mask parts
        Philips  87c748 thru 89c588 - more variants than anyone else
        Siemens  80c501 through 80c517a, and SIECO cores
        SMC      COM20051 with ARCNET token bus network engine
        SSI      80x52, 2 x HDLC variant for MODEM use

    Advanced Micro Devices (AMD)

       AMD was one of the first manufacturers of enhanced variants
       including such features as:  dual data pointers, slave interface
       with arbitration unit, dual port RAM, FIFO buffers, and others.
       They are now out of the 8051 business.


    Atmel

       The smallest current device is the ATMEL 89c1051, a 20 Pin FLASH
       variant with 2 timers, UART, 20mA.  ATMEL was the first with
       standard pinout FLASH, and with more program cycles than other
       custom pinout FLASH.  These parts compete with OTP and MASK
       product on price, but eliminate inventory problems and the hidden
       costs of OTP development.  This will put real pressure on
       "vanilla" micros like PIC and ST6.


    Dallas Soft Microcontrollers - DS5000(T), DS5001(T), DS2250(T)

       The Dallas Soft Microcontrollers have standard 8051 cores with
       on-chip non-volatile RAM instead of ROM.  This gives the user the
       ability to easily alter the system and is perfect for data
       logging.  These processors are available in both chip and module
       solutions.  Among the features included in this family of
       products:
          - on-chip non-volatile RAM
          - loader in ROM for downloading programs (eliminates the hassle
            of EPROM erase/program/install cycle)
          - built in real time clock option
          - watchdog timer
          - software security (program and data encryption)

       The DS500x is a standard 40 pin DIP package (well, mostly
       standard, it is really a BOX which is about double the height of a
       normal chip).  The DS225x is a SIP version which is functionally
       identical to the DS5000 but usually a bit less expensive.

       The nice thing about having the RAM on-chip, is that the I/O ports
       are unaffected.  When the RAM is configured as CODE memory, the
       DS5000 behaves exactly as a single-chip 8051.  The NV-RAM is
       static with a built-in lithium battery, and has no limitations on
       the number of writes.  You can download your code as many times as
       you like without damaging the device.  The DS5000 also includes a
       loader in ROM, which permits you to bootstrap code into the RAM to
       get underway.  The loader and on-chip RAM have an encryption
       feature with which you can protect your code from being read back
       from the device if you wish.


    Dallas High-Speed Micros - DS80c320, DS87c520, DS87c530

       Real barn-burners - performance up to 10 MIPS!  Dallas was the
       first to speed up the core.  Wasted clock and memory cycles have
       been removed using a redesigned processor core.  As a result,
       every 8051 instruction is executed up to 3 times faster than the
       original for the same crystal speed.  Clock speeds from DC to
       33MHz!

       High performance doesn't just mean speed.  High integration gives
       the user 2 full-duplex hardware serial ports, 13 total interrupt
       sources (6 external), watchdog timer, power management, power-fail
       reset, and other features.


    Intel MCS-51

       Introduced in 1980, it has become the industry standard for
       embedded control.  Intel offers a wide variety of 8051 versions
       with different configurations of on-board EPROM/ROM.  Also low
       power, high integration, and specialized parts are also offered.


    OKI

       OKI makes an 85c154 piggyback - an 8751 but with an EPROM socket
       on top!  Great with an EPROM emulator.


    Philips

       Philips has more 8051 variants than anyone else.  Among the
       derivatives that they have:  40MHz, 24 pin skinny DIP, low
       voltage, quad flat pack (QFP) versions for saving board space,
       OTP, I2C bus, and so on.

       The c5xx line features high integration, with many built-in
       features including built-in EMI/RFI suppression.

       The c7xx series are very low-end, inexpensive micros.  They are
       offered with less memory (1k, 2k, etc.) and fewer features.  In
       fact the 83c750 sells for only $1 in very high OEM volumes.


    Siemens sab80c517a

       The 80c517a is one of the most powerful 8051 variants available.
       It features high clock speed (40 MHz), and high integration with
       32 Bit ALU, 2 UARTS, 2K RAM, PLCC84 package, 8x16 bit PWMs, and
       more.


    Standard Microsystems Corporation SMC COM20051
       The COM20051 is an integrated microcontroller and network
       interface which features:
         -  high performance and low cost
         -  based on popular 8051 architecture
         -  drop-in replacement for 80C32 PLCC
         -  network supports up to 255 nodes
         -  powerful network diagnostics
         -  maximum 512 byte packets
         -  duplicate node ID detection
         -  self-configuring network protocol
         -  retains all 8051 peripherals including Serial I/O and
            2 Timers
         -  utilizes ARCNET(R) Token Bus Network Engine
         -  requires no special emulators
         -  5 Mbps to 156 Kbps data rate
         -  network interface supports RS-485, twisted pair,
            coaxial, and fiber optic interfaces
         -  "receive all" mode allows any packet to be received


    Silicon Systems Inc. SSI73M2910/2910A

       The SSI73M2910 is a high performance microcontroller designed for
       modem and communications applications.
         - 8052 Compatible Instruction set.
         - 34 MHz Operation @ 4.5 - 5.5V
         - 44 MHz Operation @ 4.75 - 5.5.V (2910A)
         - 22 MHz Operation @ 3.3 - 5.5.V
         - HDLC Support Logic (Packetizer, 16 and 32 CRC, zero ID)
         - 24 pins for user programmable I/O ports
         - 8 pins programmable chip select logic or I/O for memory mapped
           peripherals eliminating glue logic
         - 3 external interrupt sources (programmable polarity)
         - 16 dedicated latched address pins
         - Multiplexed latched/address bus
         - Instruction cycle time identical to 8052
         - Buffered oscillator (or OSC/2) output pin
         - 1.8432 MHz UART clock available
         - Bank select circuitry to support up to 128K of external
           program memory
         - 100-Lead TQFP package available for PCMCIA applications
         - Also available in 100-Lead QFP package


2.3)  16-bit 8051 parts


    A joint project between Intel and Philips Semiconductors has resulted
    in two new excting products - 16 bit 8051s!  Due to a disagreement
    between the parties, they each went their separate ways.  Intel
    developed the MCS-251, which was originally called the ZX (this name
    can still be found on one of the Intel slide shows).  Philips came
    out with the eXtended Architecture (XA) line.

    The Intel MCS-251 is a drop-in replacement for the 8051 (at least,
    after programming the mode control bits first), and is also binary
    compatible.  The XA is more of a 16 bit micro which also happens to
    be source code compatible.  One can argue the merits of which
    approach is better.

    Pin compatible parts allow instant performance upgrades for existing
    designs, and the binary compatibility truly preserves users
    investment in code and tools.  By staying firmly in the 80x51 camp,
    Intel allows users transparent access to an enormous horsepower
    range.  To further improve throughput in numerically intensive areas,
    users can use INTEGER, LONGINT, and FLOAT libraries written for the
    MCS-251.  The Philips XA is not a drop-in replacement for the 8051.

    Binary code compatibility is nice, you can move right up to a more
    powerful engine without having to bust a gut (We all know the Intel
    binary compatible success story with their 80x86 microprocessors).
    But if you're working on a new design, how necessary is binary
    compatibility?  If you're just looking for a souped up '51, Dallas
    already has the 320.  If you need the advanced features, you'll need
    to recompile or rewrite your software anyhow.  You'll also have to
    drag along some compatibility baggage with you in order to use the 16
    bit operations - these are preceded by an escape code (A5H), the only
    instruction not used in the 8051 instruction set.

    With source code compatibility, you have to recompile your code (with
    a new set of development tools), since the instruction set has been
    recrafted to allow the biggest bang for the buck.  This process isn't
    100% transparent, but then again, binary compatibility isn't either.

    If you're upgrading an existing design, the 251 is probably your only
    reasonable choice (although you might also want to consider the
    Dallas 320).  On new designs, you'll have a tough decision to make.
    Whichever path you choose to take, the 8051 will never be the same
    again.


    Intel MCS-251

       The Intel MCS-251 is 100% binary and pin compatible with the 8051,
       but with a 5-15 times boost in horsepower.  This is achieved by a
       six fold gain in bus cycles, and further hardware improvements to
       avoid wasted bus cycles.

       Further performance gains are possible by recoding critical
       sections to take advantage of the new features:  powerful 8/16/32
       bit instructions, flexible 8/16/32 registers, 16MB linear address
       space, 16-bit stack pointer, enhanced BIT manipulations, and
       improved control instructions.  In addition to extra 16/32 bit
       instructions, the 251 includes 40 registers with Accumulator and
       Index functions overlayed as 16x8, 16x16, 10x32.

       Should we expect a 351 in the future.  How about a 451?  Or maybe
       a Penti-uC?


    Philips 8051XA

       By tossing compatibility out the window, Philips was able to
       develop a true 16 microcontroller while at the same time
       preserving the basic 8051 instruction set (source).  The benefits
       of this break with tradition result in a chip that has dual 16MB
       address spaces (data and code), multitasking support with task
       protected memory segments, a separate SFR bus, fast context
       switching, and optimized code efficiency.  Other features include:
       hardware divide and multiply (over 100 times faster than an 8051),
       32 vectored interrupts, 16 hardware exceptions, and 16 trap
       instructions.


2.4)  8051 representatives and approximate prices (in USD $)

    There are many, many varieties of 8051 out there.  This is only a
    small sampling of typical prices on Intel chips.

        8031 (128 bytes RAM)...................................3.59
        80C31 (CMOS version of previous).......................6.95
        8051AH (256 bytes RAM).................................6.95
        8051AHBASIC (w/Basic interpreter built in)............29.95
        8751 (4K EPROM, 128 bytes RAM)........................26.95
        87C51 (CMOS version of previous)......................39.95


2.5)  Common and New 80x51 variants

    Intel has announced that 8052AH-BASIC has reached its EOL (end of
    life) and is not any more in production. Resellers may still have
    some chips in stock. However, both source and object code is
    available in many ftp-sites (and Intel BBS) and can be loaded into
    any 8052-compatible internal ROM memory (or external ROM, but then
    PROG and DMA cannot be used).

    At least few years ago, MicroMint Inc. (4 Park St, Vernon,
    CT 06066, USA) was selling their own 80C52-BASIC at USD 25, speed DC
    12 MHz, CMOS.

    <Thanks to Eero-Pekka Mand>


    Thanks to Jim Granville of Mandeno Granville Electronics, Ltd. for
    the following nice summary.

    Key:
        PCA programmable counter array
        LV  low voltage
        PWM pulse width modulation
        CC  capture/compare
        UPI Universal Peripheral Interface (Philips)

    Variant  Pins  Mfg     RAM  CODE XRAM  Notes (LV - low voltage)
    ---------------------------------------------------------------------
    MCS251    40   Intel    1K  16K    0   16 Bit 80x51FX! Prelim
    80C509L  100qf Siemens 256  64Kx  3K   ALU,PWM,CC,2UART,10bA/D
    80C517A   84   Siemens 256  64Kx  2K   ALU,8PWM,CC,2UART,10bA/D
    80C537A   84   Siemens 256  32K   2K   ALU,8PWM,CC,2UART,10bA/D
    80537     84   Siemens 256  64Kx   0   ALU,8PWM,CC,2UART,8bA/D
    80517     84   Siemens 256   8K    0   ALU,8PWM,CC,2UART,8bA/D
    73D2910 100qfp SSI     256 128Kx   0   80C52+Ports+HDLC
    80C535A   68   Siemens 256  64Kx  1K   515+10bA/D,1K XRAM,BRG,OWD
    80CE558  80qfp Philips 256  64Kx 768   Enhanced 80C552, Sep i2c, RSO
    80C515A   68   Siemens 256  32K   1K   515+10bA/D,1K XRAM,BRG,OWD
    80535     68   Siemens 256  64Kx   0   Timer2CaptComp 6ports 8/10bA/D
    80515     68   Siemens 256   8K    0   Timer2 CaptComp 4 ports 8b A/D
    80C535    68   Siemens 256  64Kx   0   Timer2 CaptComp 5 ports 8b A/D
    80C51GB   68   Intel   256  64Kx   0   8051FA+PCA, 8b A/D, SPI
    87C51GB   68   Intel   256   8K    0   8051FA+PCA, 8b A/D, SPI
    80C592    68   Philips 256  64Kx 256   552-i2c+CAN+XRAM
    87C592    68   Philips 256  16K  256   552-i2c+CAN+XRAM
    87C598    80   Philips 256  32K  256   552-i2c+CAN+XRAM
    80C552    68   Philips 256  64Kx   0   10b A/D, i2c, CaptComp, PWM
    87C552    68   Philips 256   8K    0   10b A/D, i2c, CaptComp, PWM
    80C562    68   Philips 256  64Kx   0   8b A/D, i2c, CaptComp, PWM
    SABC505C  44   Siemens 256  64Kx 256   8bA/D,XRAM,OWD,CAN V2B, Xt2
    SABC504   44   Siemens 256  64Kx 256   10bA/D,XRAM,OWD,DC Motor PWM
    87C451    68   Philips 128   4K    0   7 Ports, 1 Handshake
    80C451    68   Philips 128  64Kx   0   7 Ports, 1 Handshake
    87C453    68   Philips 256   8K    0   7 Ports, 1 Handshake
    83CL580  56,64 Philips 256   6K    0   LV 8052+ADC+i2c+More INTs,WDOG
    80C320    40   Dallas  256  64Kx   0   FAST, 2 DPTR 2 UART VRST
    80C310    40   Dallas  256  64Kx   0   Simpler 80C320 e62.5Mhz
    87C520    40   Dallas  256  16K   1K   16K OTP enhanced 80C320
    80C51FX   40   Intel   256  64Kx   0   80C58i+PCA,AsRST
    87C51FA   40   Intel   256   8K    0   8052+PCA,Enh Serial Automotive
    87C51FB   40   Intel   256  16K    0   8052+PCA,Enh Serial Automotive
    87C51FC   40   Intel   256  32K    0   8052+PCA,Enh Serial Automotive
    8XC51FB   40   Philips 256  16K    0   87C51FB with ALE RFI mode
    87C51FXL  40   Intel   256  32K    0   3.3v 80C51FC
    80C152JD  68   Intel   256  64Kx   0   HDLC/SDLC Serial
    80C152    48   Intel   256  64Kx   0   HDLC Serial
    8044      40   Intel   192  64Kx   0   RUPI Serial
    80C575    40   Philips 256  64Kx   0   8052+PCA,AnalogComp,WDOG,RSTLo
    87C575    40   Philips 256   8K    0   8052+PCA,AnalogComp,WDOG,RSTLo
    80C576    40   Philips 256   8K    0 8052+PCA,UPI,A/D,PWM,WDOG,VRSTLo
    87C576    40   Philips 256   8K    0 8052+PCA,UPI,A/D,PWM,WDOG,VRSTLo
    SABC501   40   Siemens 256  64Kx   0   40MHz Enhanced 8052 U/D
    SABC502   40   Siemens 256  64Kx 256   8052+XRAM+8DP+WD+BRG+OWD
    80C528    40   Philips 256  64Kx 256   8052+Wdog, XRAM
    87C528    40   Philips 256  32K  256   8052+Wdog, XRAM
    89CE528   44   Philips 256  32KF 256   Flash 528
    87C524    40   Philips 256  16K  256   16K 87C528
    80C550    40   Philips 128   4K    0   8b A/D WDog
    80CL781   40   Philips 256  64Kx   0   LV 8052, More INTs, WDOG
    83CL781   40   Philips 256  16K    0   LV 8052, More INTs, WDOG
    80CL782   40   Philips 256  64Kx   0   LV, faster 781
    89S8252  40.44 Atmel   256 10KFE   0   FLASH, 8K+2KEE, WDOG, SPI
    89C55    40.44 Atmel   256 20KF    0   FLASH, Fast,LV 87C52+20K
    89C52    40.44 Atmel   256  8KF    0   FLASH, Fast,LV 87C52
    87C54     40   Intel   256  16K    0   16K 87C52i
    87C58     40   Intel   256  32K    0   32K 87C52i
    87C52     40   Intel   256   8K    0   8052+U/D+OscO+4Li
    80C154    40   Matra   256  64Kx   0   Enhanced 8052 (also OKI)
    83C154D   40   Matra   256  32K    0   Enhanced 8052
    83C154    40   OKI     256  16K    0   Enhanced 8052
    80C654    40   Philips 256  64Kx   0   i2c
    87C652    40   Philips 256   8K    0   i2c
    87C654    40   Philips 256  16K    0   i2c
    83CE654  44qfp Philips 256  16K    0   i2c, low RFI 654
    DS5000    40   Dallas  128  32KR 32K   80x51 Secure+NVsupport,BootLdr
    DS2250   40sim Dallas  128  32K  32K   5000, in SIMM package
    DS5001   80qfp Dallas  128  64Kx 64K   Enhanced DS5000, RPC BatSw
    80C851    40   Philips 128  64Kx   0   8051+256B EEPROM
    83C852     6   Philips 256   6K    0   ALU,2K EEPROM SmartCard,Die
    8052      40   All     256  64Kx   0   8051+Timer2
    8752      40   Intel   256   8K    0   8051+Timer2
    80C52     40   Siemens 256  64Kx   0   8051+Timer2,Philips,Oki,Matra
    88SC54C   8    Atmel   256  64Kx 512   8052+PublicKey,prelim
    80CL410   40   Philips 128  64Kx   0   LV, More INTs i2c-UART
    80CL31    40   Philips 128  64Kx   0   LV, More Ints 80x51
    80CL610   40   Philips 256  64Kx   0   LV, More INTs i2c-UART
    83CL411   40   Philips 256  64Kx   0   80CL31 with 256 RAM, No T2
    89C51    40.44 Atmel   128   4KF   0   FLASH,Fast,LV 87C51
    8751      40   All     128   4K    0   Core processor,UART,Tmr0,Tmr1
    87C51     40   All     128   4K    0   Core processor,UART,Tmr0,Tmr1
    8031      40   All     128  64Kx   0   Core processor,UART,Tmr0,Tmr1
    8051      40   All     128   4K    0   Core processor,UART,Tmr0,Tmr1
    80C31L    40   Matra   128  64Kx   0   LV 80x51
    87C752    28   Philips  64   2KE   0   87751+ A/D, PWM
    87C749    28   Philips  64   2KE   0   87C752 - i2c
    87C751    24   Philips  64   2KE   0   Small size, bit i2c
    87C748    24   Philips  64   2KE   0   87C751 - i2c
    87C750    24   Philips  64   1KE   0   Small size
    89C2051   20   Atmel   128   2KF   0   20Pin 89C51,+AnaComp+LED
    89C1051   20   Atmel    64   1KF   0   20Pin 2051 -uart,timer1


2.6)  Advantages realized in implementing control applications on this
      family of microcontrollers

    Wildly popular - readily available and widely supported, a full range
    of free and commercial support products is available

    Fast and effective - the architecture correlates closely with the
    problem being solved (control systems), specialized instructions mean
    that fewer bytes of code need to be fetched and fewer conditional
    jumps are processed

    Low cost - high level of system integration within one component,
    only a handful of components needed to create a working system

    Wide range -  ONE set of tools covers the greatest horsepower range
    of any microcontroller family, other suppliers handle a number of
    DIFFERENT and INCOMPATIBLE (and often single-sourced) cores to cover
    the same power range as the 80x51, the 8051 provides a real cost
    savings in tools, training, and software support

    Compatibility - opcodes and binaries are the SAME for all 80x51
    variants (unlike most other microcontroller families)

    Multi-sourced - over 12 manufacturers, hundreds of varieties,
    something for everyone with the security of ready availability

    Constant improvements - improvements in silicon/design increase speed
    and power annually, 16 bit models coming from several manufacturers,
    low cost skinny DIP models now available


2.7)  Getting started

    If you are interested in getting started with the 8051, you will need
    to concern yourself with getting the appropriate hardware and
    software to develop your system.

    A good start would be to pick up a couple of books on the subject.
    Two really great books for beginners are "The Microcontroller Idea
    Book" by Jan Axelson (Lakeview Research) and "Programming and
    Interfacing the 8051 Microcontroller" by Sencer Yeralan and Ashutosh
    Ahluwalia (Addison Wesley).  Both books contain complete plans for
    microcontroller boards/systems if you plan on rolling your own.  The
    Yeralan/Ahluwalia books also contains a diskette with just about all
    of the software that you'll need to get started progamming for the
    8051 (assembler, simulator, etc).  These books also have many circuit
    and code examples and are very useful for the beginner (I'm going to
    need an extra copy of each for reading in the bathroom :-).


    Which software you choose is mostly a matter of personal preference,
    how much time you have to invest, how much money you have to invest,
    and what you want to accomplish.  Serious work can be accomplished
    using much of the free software listed in this FAQ, however in most
    cases technical support is unavailable.  Registering shareware, or
    buying a mainstream commercial package gives you backup and support
    and helps you get going much faster.

    If you are a hobbyist or student, and would like to program in C, I
    would recommend looking at the Dunfield Development System.  I use
    this package and it is a powerful package for only $100.  It includes
    a full suite of development tools including C compiler, assembler,
    linker, and much more.  A hardware-resident simulator/emulator is
    available for an additional $50.  Another C compiler package from
    Micro Computer Control provides similar capabilities for the same
    price.

    A wide range of development options exists for all budgets and
    purposes.  One convenient way to start is the Ceibo/Philips DS-750
    development system, based on the 80c75x (a scaled down 8051 variant).
    The "emulator" board programs the chips (so you won't need an EPROM
    programmer and the debugger has a user interface much like Borland's
    Turbo Debugger.

    The development system that I use is based on the Dallas DS5000.  The
    nice thing about the DS5000 is that you can upload your programs
    directly to the chip (no EPROM needed!).  The Dunfield package
    provides excellent support for this chip, including plans for
    building a "pseudo-ice".  With this setup, all you need to do is
    upload your program, and debug (emulate) on the target hardware.
    This setup is highly recommended.


    One other possibility is the 8052AH-BASIC chip.  With a Basic
    interpreter built in, you have an interactive development system when
    attached to your PC.  Jan Axelson's book gives complete coverage on
    this chip, including plans to build your own system, programming in
    Basic, and interfacing to various peripherals and devices.


    What might be the easiest way to get started, is by buying a complete
    development package. The AES-51 from American Educational Systems is
    a good example. This package comes complete with everything you need
    to get started and do real work. The microcontroller board has just
    about every peripheral you'll ever need built right in (LCD, keypad,
    A/D, D/A, I/O, etc) and comes with a built-in monitor and BASIC. Also
    included is a shelf full of tutorial and reference books and a
    diskette with the required support software for your PC. For less
    than $300, you get a complete and professionally designed and
    packaged educational tool. AES also has two other boards (based on
    the 68hc11 and 8088) which have the same basic appearance and
    functionality.


2.8)  Technical Questions and Answers

    Q:  Why are ports P0 and P2 unavailable for I/O when using external
        memory?

    A:  The output drivers of ports 0 and 2, and the input buffers of
        port 0, are used to access external memory.  Port 0 outputs the
        low byte of the external memory address, time-multiplexed with
        the byte being read/written.  Port 2 outputs the high byte of the
        external memory address when the address is 16 bits wide.
        Otherwise, the port 2 pins continue to emit the P2 SFR contents.
        Therefore, when external memory is being used, ports 0 and 2 are
        unavailable for their primary use as general I/O lines.


    Q:  Is there anything I can do to use these ports for I/O when using
        external memory?

    A1: Not really.

    A2: If you really want to make your life miserable, you can try to
        use P2 for output when it isn't being used for memory access.
        The contents of the SFR latch for port 2 are not modified during
        the execution of a Data Memory fetch cycle on the Expanded Bus.
        If an instruction requiring a cycle on the Expanded Bus is not
        followed by another instruction requiring a cycle on the Expanded
        Bus, then the original contents of the port 2 SFR latch will
        appear during the next machine cycle.  That is, when PSEN, RD and
        WR are all inactive, you can use port 2 for output (check the
        timing charts in the data book).  The chip will emit the contents
        of the P2 SFR at that time.  Do you REALLY want to bother with
        this though?

    A3: By including the external RAM "on-chip", the Dallas DS5000 makes
        these ports available for I/O.  The SLIC E2 from Xicor does the
        same thing for other 8051 parts.

    A4: If you really need the extra I/O ports, there are number of 8051
        variants that have additional ports.  Philips and Siemens are two
        such manufacturers that have these parts in their product lines.


    Q:  I'm outputting a 1 to a pin on port 0, but I'm not getting a 1
        out.  If I use a pin on port 1 instead, it works fine.  What am I
        doing wrong?

    A:  Port 0 has open drain outputs.  Ports 1, 2, and 3 have internal
        pullups.  What does this mean?  See the next question and answer.


    Q:  Port 0 has open drain outputs.  Ports 1, 2, and 3 have internal
        pullups. What does this mean, and why should I care?

    A:  When used as outputs, all port pins will drive the state to which
        the associated SFR latch bit has been set.  Except for port 0,
        which will only drive low (not high).  When a 0 is written to a
        bit in port 0, the pin is pulled low (0).  But, when a 1 is
        written to a bit in port 0, the pin goes into a high impedance
        state - or in other words, "disconnected", no value.  To be able
        to get a 1 as output, you need an external pullup resistor to
        pull up the port (to 1) when the port is in its high impedence
        state.  Typical values for pullups might be 470 ohm to drive a
        LED, and 4.7K or higher to drive logic circuits.

    C:  Any port pin may be used as a general purpose input simply by
        writing a 1 into the associated SFR latch bit.  Since ports 1, 2,
        and 3 have internal pull-up devices they will pull high and will
        source current when pulled low.  When a port 0 bit is programmed
        for input (set to 1) it will go to a high impedance state.


    Q:  Why is such an oddball crystal frequency of 11.0592 MHz used so
        often for 8051 designs.

    A1: 11.0592 MHz crystals are often used because it can be divided to
        give you exact clock rates for most of the common baud rates for
        the UART, especially for the higher speeds (9600, 19200).
        Despite the "oddball" value, these crystals are readily available
        and commonly used.

    A2: When Timer 1 is used as the baud rate generator, the baud rates
        in Modes 1 and 3 are determined by the Timer 1 overflow rate and
        the value of SMOD (PCON.7 - double speed baud rates) as follows:

                            smod
                           2
           Baud rate =   ------   x (Timer 1 overflow rate)
                           32

        Most typically, the timer is configured in the auto-reload mode
        (mode 2, high nibble of TMOD = 0100B).  In this case, the baud
        rate is given as:

                            smod
                           2        Oscillator frequency
           Baud rate =   -------  x --------------------
                           32         12 x (256 - TH1)

        Some typical baud rates for an 11.0592 crystal:

           Baud rate  SMOD   TH1
           ---------------------
             19200      1   0FDH
              9600      0   0FDH
              4800      0   0FAH
              2400      0   0F4H
              1200      0   0E8H
               300      0   0A0H

        Another way to look at it, would be to rework the formula to give
        us the crystal frequency that we need for the desired baud rate:

                                                        smod
        Minimum crystal frequency =  Baud rate x 384 / 2

        This gives us the minimum crystal frequency possible for the
        desired baud rate.  The frequency can be evenly multiplied to
        obtain higher clock speeds.

        As an example, the minimum crystal frequency for 19.2K baud is:
              3.6864 = 19200 x 384 / 2 (smod is 1 for 19.2K baud)

              11.0592 = 3.6864 x 3


        To determine the timer reload value needed, the formula can be
        changed to factor in the multiplier:
                                                             smod
        Crystal frequency = Baud rate x (256 - TH1) x 384 / 2


        From the example above, the multiplier (3) is used to determine
        TH1:
              TH1 = 256 - 3 = 253 = 0FDH

        The crystal frequency for 19.2K baud is:
              11.0592 = 19200 x (256 - 0FDH) x 384 / 2
                      (smod is 1 for 19.2K baud)


        Other values can also give good results, but 11.0592 is one of
        the higher speed crystals that allows high baud rates.

    A:  Well, you wanta talk about oddball values?  Another good crystal
        value is 7.3728 MHz and its multiples. Using counter1 this gives
        an even 38.4 kbps rate exactly, which is not possible with
        11.0952 MHz Xtal. <Thanks to Eero-Pekka Mand>


    Q:  How do I decrement the data pointer (DPTR)?  Where did the DEC
        DPTR instruction go?

    A1: You can't decrement DPTR.  Although there is an INC DPTR
        instruction, there is no DEC DPTR.  In fact, there is no other
        way to change the contents of DPTR except for MOV and INC.

    A2: You can use the accumulator as an offset if you need to perform
        "calculations" on the DPTR.  As an example:
              MOV   DPTR,#9000         ; load base address into DPTR
              MOV   A,#10              ; load desired offset
              MOVC  A,@A+DPTR          ; retrieve desired data

    A3: Another method would be to use indirect addressing.  Instructions
        such as MOVX A,@Ri can address a 256 byte "page" of external RAM.
        The value represented by @Ri (@R0 or @R1) is emitted to Port 0,
        which is the low byte of the external RAM address bus.  In
        addition, the contents of the P2 register is emitted to Port 2,
        which is the high byte of the external memory address bus.  The
        indirect addressing register together with the P2 register, which
        specifies the "current page number", gives us a 16 bit pointer
        into the external memory address space.

        This technique can make moving data in external memory much
        faster than reloading DPTR every time.  The indirect addressing
        register can be manipulated much easier than DPTR which can only
        be loaded and incremented.  Just remember to make sure that P2
        contains the proper value for the high byte of the address.

    A4: Inside the BASIC interpreter source code, and published in its
        manual, is a short and efficient subroutine to decrement data
        pointer, only 6 statements:
            XCH A,DPL ; JNZ $+4 ; DEC DPH ; DEC A ; XCH A,DPL ; RET
        Only DPTR is affected, not A or any flags!
        <Thanks to Eero-Pekka Mand>


    Q:  I'm trying to PUSH and POP the accumulator, but my assembler
        complains about the instruction  PUSH  A.  What's wrong with
        this?

    A:  In instructions that are accumulator specific, A is used to
        represent the accumulator.  However, PUSH and POP have no
        accumulator specific forms, only direct addressing forms.
        Therefore, you need to specify the correct accumulator "address"
        - ACC.  Use the instruction PUSH ACC.


    Q:  The 8052 AH-BASIC interpreter seems to work OK when I perform
        simple interpreted commands.  For example:
             READY
             > PRINT "HELLO"
             HELLO
        However, when I try to enter a [numbered] statement, I get an
        error:
             READY
             > 10 PRINT "HELLO"
             INVALID LINE NUMBER..!!
        I get the same error when I try LIST.  No matter what value I set
        a variable to, it returns a 0.  What's my problem?

    A1: Faulty memory decoding or addressing is the most common cause for
        this error message.  This happens when RD/WR is affecting two (or
        more) active memory chips. So, decode each CS very carefully!

    A2: Your address decoding might also indicate that there is more
        memory than really exists.  Go over your circuit design and
        inspect your wiring carefully.


    Q:  Can I use C for time critical code?

    A:  The code produced by many of the excellent compilers today, is
        remarkably efficient - for both speed and size.  Modern compilers
        are quite adept at keeping track of register and variable usage.
        Further optimization techiniques result in code that can be as
        good or better than hand written assembler.  Even for ISRs
        (interrupt service routines), C should be acceptable for all but
        the most time critical routines.

        Makes you think twice about breaking your head over assembly
        code.


    Q:  The Intel MCS-51 assembly language defines alternate symbols AR0
        ... AR7 for registers R0 ... R7.  What is this good for? (Thanks
        to Wolfgang Heinz who submitted this Q & A)

    A:  Some 8051 instructions do not support all possible addressing
        modes.  For example, the PUSH and POP instructions are only
        available with direct addressing. Since the registers R0 ... R7
        are mapped into the internal memory, they must also have a DATA
        (= direct) address.  The special assembler symbols AR0 ... AR7
        are simply the absolute DATA addresses of registers R0 ... R7.
        Although there is no instruction PUSH R5 with true register
        addressing, you can do it with PUSH AR5 (= direct addressing)!

    Q:  Usually the 8051 register banks are switched with the RS0 and RS1
        bits in the status register PSW at runtime.  But how is it
        possible to switch the banks at assembly time with the USING
        instruction, implemented in so many 8051 assemblers?
        (Thanks to Wolfgang Heinz who submitted this Q & A)

    A:  Not at all!  This must ALWAYS be done with bits RS0 and RS1 at
        runtime.  The USING instruction switches only the absolute DATA
        addresses of the special assembler symbols AR0 ... AR7 according
        to the selected bank number.  With most assemblers that implement
        relocatable segments and object modules, the linker is forced to
        reserve space for the corresponding register bank in the internal
        memory.


    Q:  The Intel 8x151/8x251 won't "drop-in" for an 8051. What gives?
        (Thanks to Dave Baldwin of The Computer Journal for this one)

    A:  You need to use a programmer to set a couple bits to the correct
        state.  This info is hidden away in an app note available from
        their fax-back service.




3)  SOURCES OF INFORMATION ON THE 8051


3.1)  FTP sites

    The following is a list of the various anonymous ftp sites that have
    8051 source code and programming languages.  There are many others
    that  are not listed here that contains bits and pieces.  Usually you
    can find them using Archie and searching for "8051", "AS31", "ASM51",
    "MCS-51", "MCS51", and stuff like that.

    ftp.pppl.gov (formerly lyman.pppl.gov)
        - this is a great source of 8051 stuff
        /pub/8051
        /pub/incoming - check this out for new untested/unsorted items

    ftp.funet.fi (nic.funet.fi)
        - this is a great one, too
        /pub/compilers/8051
        /pub/microprocs/MCS-51   <mirror of ftp.pppl.gov>
        other subdirectories in /pub/microprocs include:
          1802, 6805, 6811, 8048, 8096 and many other microprocessors

    ftp.intel.com
        - this ftp site is pretty good now, and getting better all the
          time!
        - send comments to:  ftp-admin@intel.com
        /pub/mcs51
        /pub/mcs51/tools - contains various development tools

    ftp.InetBSystems.us.com
        - lots of good stuff here!
        /pub/Philips-MCU/bbs
        - contains the following directories:
            .../assemblers - assemblers, disassemblers, and simulators
            .../basic - Basic utilities and interpreters
            .../forth - Forth programming tools
            .../debuggers - monitors and debuggers
            .../utilities - miscellaneous information and utilities
            .../examples - code examples
            .../unsorted - new [unsorted] files
            .../xa - files on the new XA "16 bit 8051"
        /pub/Philips-MCU/archive - email archive

    nctuccca.edu.tw
        - mirror of ftp.intel.com
        - /vendors/Intel

    ftp.zilker.net
        - /pub/philips
        - Philips "mini ftp site" set up by Phil Wood of Philips
        - lots of 8051 code and programming tools from their BBS

    ftp.mcc.ac.uk
        - this is a new 8051 ftp site
        - soon to be improved

    ftp.bsl.unsw.edu.au
        - new 8051 ftp site
        - accepting uploads

    info@circellar.com - Email (not ftp)
        - send Email to get information file on services available
        - all Circuit Cellar INK and BYTE related files available

    ftp.ee.ualberta.ca
        /pub/cookbook/digital
        - circuits of all types
        - prog51.zip is a programmer for the ATMEL 89C51 flash part
          by Werner Terreblanche

    ftp.luth.se
        /pub/languages/assembler

    asterix.inescn.pt - FORTH archive
        /pub/forth/8051

    hpcsos.col.hp.com
        /mirrors/.hpib0/forth/8051 (mirror of asterix Forth archive)
        /misc/ns32k/beowulf/a-8051
        /mirrors/.hpib0/forth/eForth

    ftp.armory.com (Steve Walz)
        /pub/user/rstevew/8051
        /pub/user/rstevew/TB8051
        /pub/user/rstevew/incoming

    ftp.oak.oakland.edu
        - has information and software for a wide range of
          microprocessors and microcontrollers, you may have to look
          around a bit

    130.123.96.9
        giovanni/51forth.zip

    ai.uga.edu
        /pub/hardware
        - stuff on the Philips 87C750/1/2 microcontrollers
        - assembler, an update for the software in the DS-750 kit,
          notebook of some early experiences and code
        - responses welcome, Michael A. Covington (mcovingt@ai.uga.edu)

    ftp.hte.com
        - HiTech Equipment Corporation's ftp site
        - information about their products including some sample code,
          a free 8051 simulator, and various things from around the net
          that relate to the 8051 family

    csd4.csd.uwm.edu - no longer supports 8051, don't even try


3.2)  Web pages

    8051 board level products
        - http://bailey2.unibase.com/local/beck04.html

    8051 Microcontrollers
        - http://www.cit.ac.nz/smac/cbt/hwsys/i8051/default.htm

    AM Research Web Site
        - http://www.amresearch.com/
        - Forth development systems and boards.

    Automation and Process Control (Olaf Pfeiffer)
        - http://www.ba-karlsruhe.de/automation/home.html
        - http://www.ba-karlsruhe.de/automation/FAQ

    Archimedes Software
        - http://www.archimedes.com/devtools

    Brian Brown's 8051 web page
        - http://www.cit.ac.nz/smac/cbt/hwsys/i8051/default.htm
        - contains Brian Brown's 8051 course
        - lots of other good stuff

    Cera/EG3 Electronic Engineers' Toolbox (home page)
        - http://www.eg3.com/ebox.htm
        - http://www.cera2.com/ebox.htm
    Cera/EG3 MCU/MPU resources
        - http://www.cera2.com/micro.htm
    Cera/EG3 Navi-GATOR (embedded development tools and chip-specific)
        - http://www.cera2.com/gator.htm

    Chip Directory and Chip Manufacturers (Jaap van Ganswijk)
        - http://www.hitex.com/chipdir           (USA, California)
        - http://www.civil.mtu.edu/chipdir       (USA, Michigan)
        - http://www.leg.ufrj.br/chipdir         (Brasil)
        - http://www.xs4all.nl/~ganswijk/chipdir (The Netherlands)
        - http://bbs.cc.uniud.it/chipdir         (Italy)

    Chipmaker web page
        - http://www.scruznet.com/~gcreager/hello5.htm
        - contains over 200 URLs of chipmakers

    Chris Burkey's (KB8ZLI) web page
        - plans for a cheap (about $10) and simple (4 chips) ROM emulator
        - ftp://ieee.cas.uc.edu/pub/electronics/software/burkey/

    Circuit Cellar Ink
        - http://www.circellar.com

    Dallas Semiconductor
        - http://www.dalsemi.com

    Gernsback Web page (Electronics Now, Popular Electronics)
        - http://www.gernsback.com
        - current issue information, recent article related files, FTP
          site, subscription information

    Emulation Technology
        - http://www.emulation.com

    FIG (Forth Interest Group) web site
        - http://www.forth.org/fig.html
        - http://www.forth.org/Forth/FAQ

    Forth, Inc.
        - http://www.earthlink.net/~forth
        - follow the links to chipFORTH, then to 8051

    French Forth web site
        - http://ourworld.compuserve.com/homepages/mp7
          maintained by Marc Petremann:
             17, allee de la Noiseraie
             F - 93160 NOISY LE GRAND
             Email: 100647.3306@compuserve.com
        - http://ourworld.compuserve.com/homepages/bioforth
          maintained by Gerard SOULA

    Gregory Pugh's homepage
        - http://sleepy.anest.ufl.edu/~glp/8051.html

    Hi-Tech Software
        - http://www.hitech.com.au
        - demo C compiler available (limits - 1K size, no library source)

    Intel MCS(R) 51 Microcontroller Family
        - http://www.intel.com/embedded/051/index.html
        - http://www.intel.com/design/usb/ (information on USB)

    S. Joel Katz's web page
        - http://www.panix.com/stimpson/micro.html
        - information about 8051 and related microcontrollers
        - not much information yet, but it is increasing rapidly

    Ken Tindell's CAN web pag
        - http://www.nrtt.demon.co.uk/can.html
        - Source code to drive the Intel 82527 CAN controller is
          available: just send e-mail to info@nrtt.demon.co.uk, with
          "Request Intel 82527 drivers" (without the quotes) in the
          subject line.

    Lakeview Research (Jan Axelson)
        - http://www.lvr.com/
        - microcontroller page (resources for 8052-Basic projects):
          http://www.lvr.com/microc.htm

    Mike Miller's 8051 Home Page
        - http://www.ece.orst.edu/serv/8051/
        - pointers to other 8051 pages
        - contains html copy of this FAQ

    Nohau Elektronik AB
        - http://www.nohau.com/nohau

    Packet Radio web page
        - http://www.tu-bs.de/studenten/akafunk/pr8051
        - Contains some schematics and code to do packet radio (AX.25)
          experiments with different types of MCS51 controllers. Packet
          radio is used by ham radio amateurs to exchange data. There is
          an almost worldwide net of PR stations.
        - The programs were written by August Gihr and they are only
          available on the packet radio net or this web page.

    Paul's 8051 Tools, Projects and Free Code
        - http://www.ece.orst.edu/~paul/8051-goodies/goodies-index.html
        - page contents: AS31 Assembler
                         PAULMON 8051 Family Monitor/Debugger
                         Low-Cost 8051 Development Board Designs
                         8051 Code Library
                         Atmel 89C2051 in-circuit programmer

    Philips
        - http://www.semiconductors.philips.com/ps/philips17.html

    The Polis research project web page
    - http://www-cad.eecs.berkeley.edu/Respep/Research/hsc/abstract.html

    Pseudocorp
        - http://www.teleport.com/~rhowden
        - New Site - products and pricing

    Richard Grant's 8051 Based Vario
        - http://cougar.stanford.edu:7878/RGvario/vario.html
        - Hang-Gliding/Paragliding WWW server. The application is an
          8751 based variometer (used by pilots to indicate the rate of
          ascent or descent). It includes schematics and assembly
          language source.

    Silicon Studio's web site
        - http://sistudio.com
        - plans for a simple, REALLY simple (2 transistors and 5
          resistors), 2051 programmer, called the BlowIT 2051

    Standard Microsystems Corporation
        - http://www.smc.com

    Steve Merrifield's 8051 home page
        - http://www.ee.latrobe.edu.au/postgrad/steve/8051.html

    Systronix web site
        - http://www.systronix.com

    Thomas Wedemeyer's SAB80C535 web page
        - http://www.zfn.uni-bremen.de/~g16i/
        - SAB80C535 based board design
        - English and German

    USB web page
        - http://www.usb.org/

    Xicor's web page
        - http://www.xicor.com/
        - 8051 code - http://www.xicor.com/xicor/menulink/link42.htm
        - 8051 microperipherals -
          http://www.xicor.com/xicor/menulink/link6.htm


3.3)  Mailing lists

    Philips-News@InetBSystems.us.com - Email (not ftp)
        - send Email with "subscribe" in the subject field to be put
          on list for newsletter
    Philips-archive@InetBSystems.us.com - Email (not ftp)
        - send Email message with the word "help" in the subject line to
          learn how to access the archive
    Philips-forum-request@InetBSystems.us.com  - Email (not ftp)
        - send an Email message with the word "subscribe" in the subject
          line to participate in the forum, and receive usage
          instructions and guidelines
    Philips-Info@InetBSystems.us.com - Email (not ftp)
        - send Email message to get information on all of Philips Email
          services


3.4)  BBSs

    The following BBSs have 8051 information:

    Blue Earth Research
        - support for their line of microcontroller boards
        - (507)387-4007

    Circuit Cellar, Inc.
        - contains code from their magazine articles and from the
          original Circuit Cellar articles in Byte magazine, also
          contains many other interesting items
        - GOOD STUFF HERE!
        - The BBS is mentioned in the masthead of each issue (on the
          table of contents page).  Excerpts from the BBS appear in Ken
          Davidson's ConnecTime column in every issue with a description
          of how to access the system at the end of every column.
        - (203)871-1988
        - Voice: (203)875-2751
        - Fax: (203)872-2204

    The Computer Journal - TCJ/DIBs BBS
        - 8051 code and assembler(s), lots of sample code
        - Forth section also with Camel51
        - 916-722-5799

    Dallas Semiconductor
        - Support for their line of innovative products

    Dunfield Development Systems
        - support for their Micro-C compiler and development tools
        - includes a lot of nice goodies - CHECK THIS OUT!
        - (613) 256-6289

    Electronics Now
        - contains code from their magazine articles
        - (516)293-2283
        - 1200/2400, 8N1

    Intel American Marketing Applications Support Bulletin Board System
        - 16 lines, hi-speed modems (14.4K)
        - Lots of useful info and files (including design examples)!
        - Full ANSI-BBS with color is recommended, but support for just
          about all terminal types is provided
        - (916)356-3600 (24 hours)
          Auto config: 1200 thru 14.4K Baud
          8 data bits, no parity, 1 stop

    Hi-Tech Software
        - +61 7 3300 5235 (Australia)

    Iota Systems, Inc.
        - Support for their line of hardware and software products
        - 15 application notes which show how to hook up such things as
          clocks, A/D, D/A, and special chips to the 8051
        - (702)831-4732

    Jens Holm's electronics BBS:
        - one of a number of BBSs that are networked over most of the
          industrial part of Europe
        - +45-86-510356 (Denmark)
        - distributes all shareware and freeware software which
          relates to electronics
        - system administrator - Jens Holm
          jholm@bjarke.nrg.dtu.dk or Jens.holm@asgaard.dk

    Massilia Underground BBS (Marseille, France)
        - +33-91794120
        - fidonet 2:323/25
        - not a commercial BBS
        - microcontroller related stuff (assemblers, debuggers,
          boards, etc), some 8051 stuff
        - everything coming in is tested

    Micro Computer Control Corporation
        - (609)466-4117

    Philips Semiconductor - Europe
        - support for: standard logic, programmable logic,
          in-car electronics (now open), 8 and 16 bit microcontrollers,
          I2C software, third party software, discrete semiconductors,
          cross assemblers (general), RF (planned)
        - PHIBBS is located in the Netherlands: +31-40-721102
        - maximum 21600 baud / V42bis / HST/Vterbo
        - 24 hours a day available
        - Help desk: +31-40-722749  (9.00 AM - 16.00 PM CET)

    Philips Semiconductor - North America
        - support for their 8051 variants
        - contains many good source code items
        - partially mirrored on ftp.pppl.gov and nic.funet.fi
        - (800)451-6644 or (408)991-2406

    PseudoCorp
        - support for their line of simulators and assemblers
        - (804)873-4838

    Realtime Control & Forth Board (RCFB)
        - Forth and assembly for the 8051
        - 300 through 14.4 baud
        - (303)278-0364 (24 hours)

    Systronix Inc.
        - support for their line of development tools
        - (801)487-2778


3.5)  Help available!

    Listed here are individuals who have expressed interest in helping
    others with hardware and software problems for 8051 systems.

    Does any one else out there think that they can help?  Just let me
    know what your areas of specialization are and I'll add your name to
    the list.  Thanks!

    Dick Barnett <rbarnett@purdue.edu>
           voice: 765-494-7497
           snail: Richard H. Barnett, PE, Ph.D.
                  Professor of Electrical Engineering Technology
                  Purdue University
                  1415 Knoy Hall of Technology
                  West Lafayette, IN 47907-1415
       Specializes in 8051 (core processors), 80C552, and 87C751
       applications.

    Mark Hopkins <mark@omnifest.uwm.edu>
       Mark is the author of the CAS assembler and of the 8051.ZIP
       programs.  He's now working on JOLT, a code generator with a
       C-like syntax.  His areas of specialization include:
       multitasking, interrupts, basic stuff (like addressing, memory
       spaces), the 8052 BASIC chip, interfacing the chip with external
       inputs and outputs

    Hans Schou <chlor@schou.dk>
       Hans is offering his assistance to users of the Standard
       Microsystems Corp. COM20051.  He's not an expert, but he has some
       experience with it.

    Neville Miles <nevm@scitec.com.au or nmes@ozemail.com.au>
       Applications and programming the Intel 8051.  He's also using
       Atmel parts if you need help with these.

    Steve <paxit@inetnebr.com>
       Steve has designed hardware and written software for the Atmel
       AT89C1051, Intel 87C52, and Philips 87C751, and has also built a
       programmer for the Atmel AT89C1051. He knows both hardware and
       software.


4)  8051 PRODUCTS

    This section includes descriptions and references to free and
    commercial software for the 8051.  FTP sites and BBSs contain many
    quality packages and code samples for free.  For heavy duty use, you
    might prefer the many commercial packages that are available.  With
    the public domain (or free) stuff, you're usually on your own.  The
    commercial packages usually provide extensive documentation and
    support.


4.1)  Free languages and development tools

    The following is a list of the languages and development tools that I
    could find on the net.  Nearly all of them include source code,
    however not all are public domain.

    Assembler

      Program: asem5112.zip
      Description: 8051 cross assembler for MS-DOS, freeware
      Author: W.W. Heinz
      Location: ftp.ix.de : /pub/elrad/023
                oak.oakland.edu : /SimTel/msdos/crossasm
                garbo.uwasa.fi : /pc/assembler

      Program: ML-ASM51.ZIP
      Description: MetaLink's 8051 family macro assembler
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs
                 http://www.psyber.com/~tcj/tcjtools/ml-asm51.zip

      Program: A51.ZIP
      Description: PseudoSam 8051 Cross Assembler
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs

      Program: AS31.ZIP
      Description:  C source for an 8051 assembler, and a simple monitor
      Author:  Ken Stauffer
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs
                 ftp.uu.net
                 oak.oakland.edu : /pub/msdos/crossasm/as31.zip
                 many other locations (use Archie to find)

      Program: CUG292WK.ZIP
      Description:  C source for a cross assembler, includes 8051
      Author:  Alan R. Baldwin
      Location:  oak.oakland.edu : /pub/msdos/crossasm
                 pc.usl.edu : /pub/msdos/systools
                 many other locations (use Archie to find)

      Program: Frankenstein
      Description:  C source for a cross assembler, includes 8051
      Author:  Mark Zenier
      Location:  ftp.njit.edu : /pub/msdos/frankasm/FRANKASM.ZOO
                 lth.se : /pub/netnews/alt.sources/volume90/dec
                 ftp.uni-kl.de : /pub1/unix/languages/frankenstein.tar.Z
                 many other locations (use Archie to find)

      Program:  CAS 8051 assembler
      Description:  Experimental one-pass assembler for the 8051
                    with C-like syntax.  Includes assembler, linker
                    and disassembler.
      Author:  Mark Hopkins
      Location:  ftp.pppl.gov : /pub/8051/assem
                 ftp.funet.fi : /pub/microprocs/MCS-51/csd4-archive/assem

      Program:  a51
      Description:  Portable cross assembler (source in C), other
                    processors available
      Author:  William C. Colley, III
      Location:  hpcsos.col.hp.com : /misc/ns32k/beowulf/a-8051

      Program:  TASM
      Description:  Table driven cross-assembler for DOS, supports
                    many different microcontrollers and microprocessors
      Author:  Speech Technology Inc.
      Location:  various different places

      Program: HASM, HSIM
      Description: A configurable Makroassembler/Simulator
      Comment:  Only for private, educational, and evaluation use
                Only available in German
      Author: Dipl.- Ing. H.P. Hohe
      Location: ftp.ix.de:pub/elrad/022/hasm18.zip
                ftp.ix.de:pub/elrad/022/hasm18.txt
                  and mirrors of ftp.ix.de

      Program:  as
      Description:  Portable cross assembler for (8051, TMS, PIC,
                    DSP5600, 68hc11).
      Comments:     Original version in German only. Turbo Pascal source
                    available for free. Unix version comes in source
                    form and is compilable in German or English.
      Author:  Alfred Arnold
      Location: ftp.uni-stuttgart.de : /pub/systems/msdos/programming/as
                  (original version in Turbo Pascal)
                sunsite.unc.edu:
                     /pub/Linux/devel/lang/assemblers/asl-1.41r5.tar.gz
                  (new C version for Unix systems)


    Basic

      Program:  BASIC52.ZIP (BASIC-52.ZIP)
      Description:  Source files for original BASIC 52 interpreter
      Author:  Intel Corporation, Embedded Controller Operations
      Location:  ftp.intel.com : /pub/mcs51
                 ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs

      Program:  BAS051.ZIP
      Description:  Converts IBM BASIC to 8051 assembly (compiler)
      Author:  Winefred Washington
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/8051/signetics-bbs

      Program:  BASIC31.ZIP
      Description:  BASIC-52 interpreter for 8031/8051 in external EPROM
      Author:  Intel w/ changes by Dan Karmann
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs

      Program:  TB-51.ZIP
      Description:  TinyBASIC for 8031
      Author:  JHW (from Intel InSite library) w/ fixes by Tom Schotland
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs

      Program:  TB51ML23.ZIP
      Description:  MetaLink ASM compatible tiny BASIC
      Author:  adapted for MetaLink assembler by Jim Lum
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs


    Forth

      Program:  EFORTH51.ZIP
      Description:  eFORTH environment for the 8051
      Author:  C. H. Ting
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs
                 asterix.inescn.pt : /pub/forth/8051
                 hpcsos.col.hp.com : /mirrors/.hpib0/forth/eForth

      Program:  FORTH51.ZIP (FORTH86.ZIP used as host)
      Description:  FORTH development system for 8051 with PC host
      Author:  William H. Payne, the author of "Embedded Controller
               Forth for the 8051 Family"
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs
                 asterix.inescn.pt : /pub/forth/8051
                 hpcsos.col.hp.com : /mirrors/.hpib0/forth/8051

      Program:  XD8051.ZIP
      Description:  Development environment for use with F-PC Forth
      Author:  Paulo A.D. Ferreira
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs

      Program:  51FORTH.ZIP
      Description:  Subroutine threaded Forth
      Author:  Scott Gehmlich
      Location:  hpcsos.col.hp.com : /mirrors/.hpib0/forth/8051
                 130.123.96.9 : /giovanni/51forth.zip

      Program:  FORTH552.ZIP
      Description:  A Non-Standard Forth System for the Signetics 80C552
      Author:  Alberto Pasquale
      Location:  asterix.inescn.pt : /pub/forth/8051
                 hpcsos.col.hp.com : /mirrors/.hpib0/forth/8051

      Program:  CamelForth/51
      Description:  ANSI Standard Forth for the 8051 family
      Author:  Brad Rodriquez
                  email: bj@headwaters.com
                  amateur packet radio: VE3RHJ@VE3IJD.#CON.ON.CAN.NA
      Location: ftp://ftp.taygeta.com/pub/Forth/Camel/

      Program:  8051 eForth
      Description:  Public Domain optimized eForth for 8051 and 68HC11,
                    written in native UCASM assemblers.
      Comments:  Most of the documentation is in German.  Supplied with
                 EFTERM terminal emulator.
      Author:  W. Schemmer
      Location:  Available for $25 from:
                 Offete Enterprises, 1306 South B Street
                 San Mateo CA 94402
                 (415)574-8250


    Development systems

      Program:  8051.zip
      Description:  Many development tools including: debugger, monitor,
                    LCD and stepper moter driver, communications, host
                    client, and much more.  This is a great collection of
                    tools.
      Author:  Mark Hopkins
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/csd4-archive

      Program:  RISM and IECM51.EXE compatible host system
      Description:  RISM is a reduced instruction set monitor and
                    IECM51.EXE is its compatible host system for a PC
      Comments:  These two programs together constitute a bare-bones
                 method of developing 80C51 system code without an
                 emulator.  RISM51X is installed in the target system
                 and connected to a host PC system through a serial port.
                 The host PC runs the debugger IECM51.EXE.  Once the
                 system has been debugged, RISM can be removed and the
                 target can be run in stand-alone mode.
      Author:  Intel
      Location:  ftp.intel.com : /pub/mcs51/tools

      Program:  ApBUILDER 2.0
      Description:  Development system for the Intel MCS-51(R) family
                    (also for the MCS-96(R) family, 80x186, and 80x386
                    embedded microcontrollers).
      Comments:  Requires Windows 3.1
                 APBUILDR.TXT - description in ASCII
                 APBDISK1.EXE - binary self-extracting file for disk 1
                 APBDISK2.EXE - binary self-extracting file for disk 2
      Author:  Intel
      Location:  ftp.intel.com : /pub/mcs51 and /pub/mcs96

      Program:  FXDSMAN.EXE
      Description:  8xC51Fx data sheets and manual in Windows 3.1
                    hypertext style
      Comments:  binary self-extracting file for one diskette
      Author:  Intel
      Location:  ftp.intel.com : /pub/mcs51/80c51

      Program: sim51d
      Description:  Shareware Simulator in German
                    DM 50 to register for full version
      Author:  Werner Hennig-Roleff
      Location:  ftp.pppl.gov : /pub/8051/hannover

      Program: PDS51.ZIP or EXE or
               PDSxxx.ZIP where xxx represents the version number
      Description: This is the IDE for the Philips PDS51 system. It
                   contains a simulation engine and can therefore be run
                   in a standalone mode. Great for evaluating the PDS51
                   product or just as a full environment simulator.
      Location: Philips North America BBS (800)451-6644, (408)991-2406
                http://www.he.net/~adr
                CompuServe:
                   Software Development Forum, Embedded Systems Section
                     (GO CLMFOR)
                   PC Programming Forum, Tools/Debuggers forum
                     (GO PCPROG)

      Program: NoICE
      Description:  PC-hosted debugger (NOT a simulator) for use with a
                    variety of microprocessor targets (Z80/Z180, Z8,
                    8051, 80(1)96, 6809, 68HC11, 65(C)02, M50740/M38000,
                    TMS370, and H8/300). The debugger consists of a
                    target-specific DOS program, NOICExxx.EXE, and a
                    target-resident monitor program (about 1K code).
      Comments:  Shareware.  The distributed version is fully functional.
                 Registration is $25 in the US, $30 elsewhere.
      Author:  John Hartman <102203.1513@compuserve.com>
      Location: any Simtel archive/mirror
                    or
                CompuServe:
                   GO SDFORUM, library section 12, embedded systems
                   GO IBMFF, do keyword search for "NoICE"
                    or
                The Circuit Cellar BBS at 860-871-1988

      Program: sim552vq.zip
      Description:  8051/80C552 simulator (Freeware)
      Comments:  Program is capable of reading .HEX and .S19 records, or
                 saving memory to a file.  It supports both code and
                 data.  Written in Turbo Pascal for XT and upwards.
      Author:  Brian Brown
      Location:  cscnt.cit.ac.nz : /pub/intel/sim552v1.zip

      Program: HASM, HSIM
      Description: A configurable Makroassembler/Simulator
      Comments: Only available in German
      Author: Dipl.- Ing. H.P. Hohe
      Copyright: Only private , Education and evalutation use
      Location: ftp.ix.de:pub/elrad/022/hasm18.zip
                ftp.ix.de:pub/elrad/022/hasm18.txt
                  and mirrors of ftp.ix.de

      Program: Emily52
      Description:  simulator
      Comments:  Shareware.
      Author:  Dunfield Development Systems
      Location: any Simtel archive/mirror

      Program: BlowIT
      Description:  Atmel 2051 programer
      Comments:  Freeware
      Author:  Silicon Studio
      Location: http://sistudio.com/


    Real-Time Operating Systems (RTOS)

      Program:  TERSE
      Description:  - Signature-Scheduled dataflow operating system
                    (RTOS) developed for embedded single-processor and
                    distributed microcontroller systems.  Easy to use,
                    very compact, and encourages totally deterministic
                    and safe performance.
                    - The first implementation is for the 8051 family,
                    and occupies from 260 to 450 bytes, the latter
                    offering network support.
                    - public domain
      Comments:  Also available is a new type of "terse-Case" development
                 methodology, particularly suited to embedded distributed
                 systems.
      Author: Barry Kauler
              Department of C & C Engineering
              Edith Cowan University, Joondalup Drive
              Joondalup, WA 6027, Australia.
              Email: b.kauler@cowan.edu.au
      Location:  WWW - ftp://scorpion.cowan.edu.au/pub/terse/


4.2)  Free C compilers

    There is finally a free C compiler for the 8051.  The Retargetable
    Concurrent Small C (RCSC) compiler is featured in an article in the
    August 1997 Dr. Dobbs. RCSC is downloadable from Dr. Dobb's at:
        http://www.ddj.com
        ftp://ftp.mv.com/pub/

    Several commercial C compilers have evaluation versions available.
    These are not too useful (even for hobbyist projects) since they
    usually don't include libraries.  However, they do afford the user
    the chance to inspect the quality of the code generated.

    In most cases, it makes more sense to invest a bit, and get something
    serious.  Also, by buying a commercial package, you have the
    advantage of having the documentation, and being able to get
    technical support.  As Hershel Roberson says about the Dunfield
    package, "It is certainly worth the money. It is probably 3/4 as good
    as compilers that cost 10 times as much!"

    There are three low-cost C compilers currently available for 8051
    development:

    Dunfield Development Systems

    I've been using the Dunfield Development System, and its really quite
    nice.  I've also heard many good things about it from others.  For
    $100 you get a near ANSI-C compiler, run-time library with source,
    assembler, ROM debugger, integrated development environment, monitor
    with source, utilities, and other extras.  A high quality simulator
    for only $50 is also available separately.  The simulator has an
    option allowing you to interface to your target by using an on-chip
    monitor.  Although not freeware, the low price, the features, all of
    the extra goodies, and the good reviews make this a package worth
    looking at.  Also, if you're interested in working on more than one
    family of microcontroller, Dunfield supports a wide range.  This
    means only needing to learn one system, instead of many.

          Dunfield Development Systems
          P.O. Box 31044, Nepean, Ontario Canada   K2B 8S8
          (613)256-5820   Fax: (613)256-5821
          BBS: (613)256-6289
          Web:   http://www.dunfield.com
          Email: General information:      info@dunfield.com
          Sales inquiries/Administration: sales@dunfield.com
          Technical inquiries/Support      tech@dunfield.com

    Micro Computer Control Corporation

    Another low priced ($100) C compiler comes from Micro Computer
    Control.  This package was unavailable for review, but according to
    the manufacturer, it features:  Cross compilers running under DOS are
    available for the 8051 and the Z8 (including Super-8).  This package
    includes a C compiler, assembler, linker, librarian, and extensive
    printed documentation.  A simulator/source code debugger is available
    for an additional $79.95.  The simulator is completely configurable,
    so much so that you don't even need the target hardware to test with.
    You can configure all I/O and other features of your target chip or
    environment.

          Micro Computer Control Corporation
          PO Box 275, 17 Model Ave., Hopewell, NJ  08525
          (609)466-1751   Fax: (609)466-4116   BBS: (609)466-4117
          Email: 73062.3336@compuserve.com

    SPJ Systems

    C-31 is a new cross compiler from SPJ Systems.  The full package
    which costs $150 (USD) includes a C compiler (ANSI compatible
    subset), assembler, source linker, and simulator (source code
    debugger).  Compiler features include: support for floating point
    numbers, extensive collection of library routines, support for using
    Special Function Registers (SFR), assembly language interface,
    peripheral keyword (allows specifying an address of a standard
    peripheral).

    The simulator allows source level debugging.  A few memory mapped
    hardware peripherals are simulated including an LCD display, 8279
    keyboard processor, and an 8255 parallel port.  (SPJ also has a plain
    simulator available as a separate product for assembly/machine code
    debugging.)

    A working demo of the compiler package, which includes the library
    sources and permits the compilation of small programs, is available
    from their web site.  This is a new package with a few rough edges,
    but it easy to use, has a decent price, and has good potential.
    Check out the demo on their web site and see for yourselves.

          SPJ Systems
          114, Chitrashala Bldg.
          562, Sadashiv Peth
          Pune, India
          Phone: 91-212-451607   Fax: 91-212-480285
          Email: spjs@giaspn01.vsnl.net.in
          Web:   http://www.prime-digest.w1.com/spj


4.3)  Commercially available products

    Many firms (large and small) offer a variety of 8051 microcontroller
    variants, programming languages, support packages, and development
    systems.

    No endorsement is implied by inclusion in this list.  I apologize to
    anyone I left out;  It's only because I didn't know about you.  If
    you want to be included in this list, just drop me a line - please.
    Any corrections and additions appreciated.

    C compilers ($$$ - high, $$ - medium, $ - low priced)
        - 2500 A.D.
        - Archimedes Software  $$$ & $$
             same as Keil Electronics C
             Archimedes is introducing StartRight, a low cost 8051 C
                compiler for $700
        - Avocet Systems  $$
             repackaging of the Hi-Tech Software C compiler
        - BSO/Tasking  $$
        - Crossware Products
        - Dunfield Development Systems  $
             Complete C compiler development system for MS-DOS
             includes: compiler, run-time library with source, assembler,
                ROM debugger, integrated development environment, monitor
                with source, utilities, and other extras
             low price:  $100
             good reputation and good support
             works well with the Dallas DS5000/DS2250
        - Franklin Software  $$ ? (new prices)
             now marketing their own C compiler
             includes: PC-Lint and an IDE
        - IAR Systems
             IAR tool kit comes with a C-Cross compiler, assembler,
                Xlink linker, Xlib librarian, C-SPY simulator, editor,
                make utility and a real-time kernel
             formerly licensed for distribution in the US and Canada
                under the Archimedes brand name
        - Hi-Tech Software  $$
             assembler, C compiler, linker, library, serial port
                debugger, and Windows style integrated development
                environment
             ANSI C and IEEE 32 float compatable with some very useful
                extensions
             $900US
        - Intermetrics Microsystems Software, Inc.
             Whitesmith's compiler, assembler, and C source level
             debugger
        - Keil Electronics  $$$
             compiler, assembler, debugger, real-time kernel, ROM
                monitor, libraries for special 8051's to set SFR,
                embedded I/O devices, A/D, etc.
        - Mandeno Granville Electronics, Ltd
             SYS51C - ANSI C Cross Compiler
        - Micro Computer Control  $
             Developer's kit includes "C"-like compiler, assembler,
                linker, librarian, extensive printed documentation
             low cost ($99.95)
        - Okapi Systems
        - Production Languages Corporation
             DOS- and Windows- based compilers
             Integrated development environment includes ANSI C compiler,
                assembler, linker, librarian, debugger
        - Signum Systems
        - SPJ Systems  $
             low cost ($150.00)

    Basic interpreters/compilers
        - Binary Technology, Inc.
        - Iota Systems, Inc.
             Basic-752 interpreter (simulator also available)
             Basic-52 Plus interpreter
        - MDL Labs
             BASIKIT--Integrated Programming Environment for BASIC-52,
                and for MDL-BASIC-I, MDL-BASIC-P, and MDL-BASIC-D.
    BASIKIT includes a full-screen editor and permits writing
                programs with labels rather than line numbers.
             MDL-BASIC-I and MDL-BASIC-P are supersets of the original
                BASIC-52, for the Intel 8052 and the Philips PCB83C552.
             MDL-BASIC-D is a BASIC for the Dallas 87C530 which accesses
                all the features of the chip, including both serial
                ports, the Watchdog, and the power-saving features. The
                BASIC will address up to 512K of memory and will collect
                data into that memory via serial port interrupts. It runs
                faster at 25 MHz than compiled code on the 8052.
        - Micro Future
             Basic-52 development system
        - Systronix Inc. (Basic compiler)

    Pascal
        - Mandeno Granville Electronics, Ltd
             PASCAL51 - Advanced Turbo PASCAL compliant cross compiler
        - Scientific Engineering Labs

    Modula-2
        - Mandeno Granville Electronics, Ltd
             Mod51 - optimizing Modula-2 Compiler, smallest program is 14
             bytes, ideal for both very tight/fast projects and very
             large ones with multiple modules, produces smaller/tighter
             code than C, has extensive libraries and working examples
        - Vail Silicon Tools, Inc.

    PL/M
        - BSO/Tasking

    Board level products
        - Ackerman Computers Sciences (ACS)
        - AM Research
             complete FORTH based system with PC based host system
        - Binary Technology, Inc.
        - Blue Earth Research
        - Blue Ridge Micros (8031 and 8052-BASIC based boards)
        - CG Microsystems
             MCU system based on the DS80C320
             piles of features including 2 ISA slots
             about $90 for the basic system
        - Circuit Cellar Inc.
        - DataCraft International
        - Dunfield Development Systems
        - EE Systems
        - Forth, Inc.
        - HiTech Equipment Corp.
        - Iota Systems, Inc. (line of development packages, boards,
             peripherals, and components)
        - J & M Microtek, Inc.
        - L.S. Electronic Systems Design
        - Mandeno Granville Electronics, Ltd
        - New Micros
             8051 based NMIY0031 SBC
             $39 + shipping you
             includes: SBC with 8051 (Siemens SAB8051, can be
                substituted), 8K RAM, EPROM with a burnt-in monitor which
                supports downloading hex files into the RAM and executing
                them
             the board can accept 3 memory chips (each one up to
                32K), one of which is for program, one for data and the
                third can be configured as wanted
             it has a 4x5 matrix keyboard interface, LCD interface,
                RS232 and support for RS422/485 (need to add the chips)
    prototyping area of about 3.5 x 2 inches
             on floppy you get:  User manual for the board in Word
                and plain text formats with many programming examples in
                all supplied languages (about 150 pages), A51 assembler,
                Small C compiler, hex file for the MCS-52 Basic
                interpreter EPROM with MCS-52 manual, hex file for
                MAX-FORTH interpreter EPROM with documentation, hex file
                for the supplied monitor and documentation, and a
                terminal program
        - Parallax, Inc.
        - Prologic Designs
        - Rigel Corporation
        - Software Science
             nice boards with prototyping area
        - Suncoast Technologies
        - URDA, Inc.

    Assemblers
        - 2500 A.D.
        - Archimedes Software
             same as Keil Electronics
             Archimedes is introducing StartRight, a low cost 8051
                assembler for $200
        - BSO/Tasking
        - Crossware Products
        - Custom Computer Consultants
        - Cybernetics Microsystems
        - Dunfield Development Systems
             Supports both Intel and Motorola style syntax
        - Emulation Technology, Inc.
        - Intel Corporation
        - Keil Electronics
        - Lear Com Company
        - Metalink
        - Micro Computer Control
        - Microtek Research
        - Nohau Corporation
        - Okapi Systems
        - Onset Computer Corporation (8051 Assember for MAC)
        - Parallax, Inc.
        - PseudoCorp
        - Raven Computer Systems
        - Signum Systems
        - Speech Technology Inc.
             TASM (table driven cross assembler supports many different
             microcontrollers and microprocessors)
        - Universal Cross Assemblers
             CROSS32 supports 40-50 different processors

    Forth
        - AM Research
             Development system, features kernel of less than 700 bytes
        - Forth, Inc.
             A cross-development product for the 8051 family
                which includes a board and extensive documentation.
        - Forth Systeme
        - MPE: MicroProcessor Engineering Ltd.
             A cross-development system for the 8051 family
                extensive documentation
             interactive single chip development, multitasking,
                bank switching for more than 64k code
        - Offete Enterprises
             8051 eForth (C. H. Ting -- $25.00).  "A small ROM based
                Forth system ... Source code is in MASM IBM 5.25 disk
                with 8051 eForth Implementation Note."

    ROM Monitor-based Debuggers
        - ChipTools (ChipView-51 looks like turbo debugger)
        - Dunfield Development Systems
             Can be used with DS5000 for single-chip in-circuit
                emulation

    Simulators
        - 2500 A.D.
        - Avocet Systems
        - ChipTools
             on a 33 MHz 486 matches the speed of a 12 MHz 8051
        - Crossware (simulator running under Windows)
        - Cybernetic Micro Systems
        - Dunfield Development Systems
             Low cost $50.00
             500,000+ instructions/second on 486/33
             Can interface to target system for physical I/O
             Includes PC hosted "on chip" debugger with identical user
                interface
        - HiTech Equipment Corp.
        - Hitex
        - Iota Systems, Inc.
        - J & M Microtek, Inc.
        - Keil Electronics
        - Lear Com Company
        - Mandeno Granville Electronics, Ltd
        - Micro Computer Control Corporation
             Simulator/source code debugger ($79.95)
        - Microtek Research
        - Production Languages Corp.
        - PseudoCorp

    Emulators ($$$ - high, $$ - medium, $ - low priced)
      <Thanks to Alistair George for this bit of important advice...
      Potential customers of emulators should check to make sure that the
      emulator supports the required external hardware (ports,
      interrupts, etc) before they buy - its probably the most
      important spec, but one easily missed. Some emulators only offer
      very minimal support, which sometimes hardly makes it worthwhile to
      bother.>
        - Advanced Micro Solutions  $$
        - Advanced Microcomputer Systems, Inc.  $
        - Applied Digital Research Ltd.  $$
        - American Automation  $$$  $$
        - Applied Microsystems  $$
        - ChipTools (front end for Nohau's emulator)
        - Cybernetic Micro Systems  $
        - Dunfield Development Systems $
             plans for pseudo-ice using Dallas DS5000/DS2250
             used together with their resident monitor and host debugger
        - Emulation Technology, Inc. $$
             OpenEmulator in-circuit emulators adaptable for over a
                hundred microcontrollers/microprocessors
        - HBI Limited  $
        - Hewlett-Packard  $$$
        - HiTech Equipment Corp.
        - Hitex  $$
        - Huntsville Microsystems  $$
        - Intel Corporation  $$$
        - Kontron Electronics  $$$
        - Lauterbach Datentechnik GmbH
             8051 In-Circuit Emulators based on a universal high-
                performance emulation system called TRACE32.
        - Mandeno Granville Electronics, Ltd
             full line covering everything from the Atmel flash to the
                Siemens powerhouse 80c517a
        - MetaLink Corporation  $$  $
        - Nohau Corporation  $$
        - Orion Instruments  $$$
        - Philips $$ $
             DS-750 pseudo-ICE developed by Philips and CEIBO
                real-time emulation and simulator debug mode
                source-level debugging for C, PL/M, and assembler
                programs 8xC75x parts
                low cost - only $100 from Philips ($250 from CEIBO)
                DOS and Windows versions available
             PDS51 board level In-Circuit Emulation system
                no stolen resources
                Daughter boards support wide range of Philips derivatives
                approximately $US1000 to $US1200 depending on daughter
                  board
        - Signum Systems  $$
        - Sophia Systems  $$$
        - Zax Corporation
        - Zitek Corporation  $$$

    Real-time
        - Byte-BOS Integrated Systems
             small, prioritized, preemptive real-time kernel
        - Embedded System Products (formerly A.T. Barrett and Associates)
             ROMable embedded-system kernel: source provided.  Provides
             programming interface identical on all target platforms.
             Basic, advanced, and extended library packages available.
        - Intellimap Engineering
             DCE51 real time operating system
        - JMI Software Systems, Inc.
             small, prioritized, preemptive real-time kernel
        - StarCom
             CRTX, embedded real-time micro kernel primarily intended for
             embedded 8-bit applications using 8051, 68HC11, 80188 etc.
             Simple, low cost, and includes ANSI C source for
             portability.
        - U S Software
             SuperTask! - multitasking executive

    Trainers
        - Advanced Educational Systems (AES)
             complete learning system (board, LCD, keypad, A/D, D/A, etc)
        - Sun Equipment Corp.
             trainers

    Miscellaneous
        - Creative Applications Engineering, Inc
             CheepTools (integrated environment)
        - Dallas Semiconductor
             evaluation/development kit for their DS5000 (very nice)
        - Data Sync Engineering (disassembler)
        - Datarescue
             IDA - an interactive, multi-os disassembler supporting:
             OS/2, Win95, Win NT, Win, NLMs and more. Unlike other
             disassemblers, IDA works with you, allowing you to modify
             the disassembled code "on the fly". It supports many
             processors, various input file formats, and can produce
             various output files etc.  IDA has a built-in C-like
             language and sports a TVision user interface.
        - Educational Laboratories
             development courses:
               8051 Microcontroller Based Computer Design
               Programming 8051 Based Computers
             each course $19.95, both $29.95
        - Electronic Product Design, Inc.
             development system (integrated package with assembler,
             project manager, text editor, programmer)
        - Exor Inc. (ladder logic compiler)
        - Feger + Co.
             offers a series of German language 8051 related books they
             call `MC-Tools' describing the processors and/or projects
             for PC-addin boards:
             MC-Tools 1 - 80c535 project for DM 119; includes 260 page
               book, an empty PCB, and a diskette with assembler,
               debugger, PC-Oscilloscope
             MC-Tools 4 - same as above but based on 80c537
             MC-Tools 3 - Die 8051-Microcontroller Familie vom 8051 zum
               80C517A; text book on the 8051 and Siemens derivatives,
               360 pages.
             MC-Tools 5 - handbook on the 80C517 and 80C517A, 360 pages
        - Iota Systems, Inc.
             integrated environment system
        - Mandeno Granville Electronics, Ltd
             PIC to 8051 conversion program
        - Parallax, Inc.
             programmers
        - Philips
             87C51 programmers
               LCPx5x - 24 and 28 pin DIL and 68 pin PLCC Philips parts
                      - 748, 749, 750, 751, 752, 451, 453, 552
               LCPx5x40 - 40 pin DIL or 44 pin PLCC Philips parts
               Range further expanded by adaptors
               Low cost, board level
        - Quantasm Corp.
             ASMFLOW - produces flowchart and tree diagrams from source
                code, register usage analysis, Xref, timing info
        - TCG
             EPROM emulator
             Atmel 2051 programmer
        - U S Software
             USNET - TCP/IP networking suite
             USFiles - file system
             GOFAST - floating point library
        - Xicor
             SLIC2E microperipherals - wires up directly to an 8051 and
               needs no glue logic, contains:
                  - 8K x 8 EEPROM in individual 4K segments
                  - 2 8-BIT I/O ports
                  - 16 8-BIT RAM registers
                  - Integrated Interrupt Controller Module
                  - Internal programmable address decoding
                  - code loaded at the factory allowing users to
                    download programs into EEPROM
             Development Support package includes a DATA BOOK, a
               SAMPLE of the CHIP (PDIP or PLCC, your choice) and PC
               compatible software for downloading and testing your
               programs. $15
             Development system includes a populated board. $180


    2500 A.D.       109 Brookdale Ave., Box 480, Buena Vista, CO  81211
                    (719)395-8683

    Ackerman Computer Sciences (ACS)
                    4276 Lago Way, Sarasota, FL  34241
                    (813)377-5775   Fax: (813)378-4226

    Advanced Educational Systems (AES)
                    1407 North Batavia Street, Orange, CA  92677
                    (800)730-3232   (714)744-0981   Fax: (714)744-2693

    Advanced Micro Devices
                    901 Thompson Place, PO Box 3453
                    Sunnyvale, CA  94088-3000
                    (408)732-2400

    Advanced Microcomputer Systems, Inc.
                    1321 NW 65th Place, Fort Lauderdale, FL 33309
                    (305)975-9515  Fax: (305)975-9698

    Advanced Micro Solutions
                    1033 S Imperial Dr., Hartland, WI 53029
                    (414)367-3577

    American Automation
                    2651 Dow Avenue, Tustin, CA  92680
                    (714)731-1661

    AM Research     4600 Hidden Oaks Lane, Loomis, CA  95650
                    (800)949-8051   (916)652-7472   Fax: (916)6642
                    BBS: (916)652-7117
                    Email: support@amresearch.com
                    http://www.amresearch.com

    Applied Digital Research Ltd.
                    P.O. Box 6480, Wellesley St, Auckland, NEW ZEALAND
                    +64 9 480-8827
                    Email: rossmcm@adr.co.nz
                    Compuserve: 100351,716
                    WWW: http://www.he.net/~adr/



    Applied Microsystems
                    5020 148th Ave. N.E., PO Box 97002
                    Redmond, WA  98073-9702

    Archimedes Software
                    2159 Union St., San Francisco, CA  94123
                    (415)567-4010
                    WWW: http://www.archimedes.com/devtools

    Ashling Microsystems Ltd
    Ireland         Plessey Technological Park
                    Limerick, Ireland
                    +353 61 334466   Fax:  +353 61 334477
    United Kingdom  Butler House
                    19-23 Market Street
                    Maidenhead, Berkshire,  UK
                    +0628 773070   Fax: 0628 773009

    Atmel           2125 O'Nel Drive, San Jose, CA  95131
                    (800)365-3375  (408)441-0311   Fax: (408)436-4300

    Avocet Systems  120 Union St., Rockport, ME  04856
                    (800)448-8500  (207)236-9055   Fax: (207)236-6713

    Binary Technology, Inc.
                    PO Box 541, Carlisle, MA  01741
                    (508)369-9556   Fax: (508)369-9549

    Blue Earth Research
                    165 W. Lind Ct., Mankato, MN  56001-0400
                    (507)387-4001   Fax: (507)387-4008
                    BBS: (507)387-4007

    Blue Ridge Micros
                    2505 Plymouth Rd., Johnson City, TN  37601
                    (615)335-6696   Fax: (615)929-3164

    BSO/Tasking
    International   333 Elm Street, Dedham, MA  02026-4530
                    (800)458-8276  (617)320-9400  Fax: (617)320-9212
    Europe          Tasking Software BV
                    P O Box 899, 3800 AW Amersfoort, Netherlands
                    +31 33 558584   Fax: +31 33 550033

    Business Data Computers
                    P.O. Box 1549, Chester, CA  96020

    Byte-BOS Integrated Systems
                    P.O. Box 3067, Del Mar, CA 92014
                    (800)788-7288   (619)755-8836

    CG Microsystems
                    http://home.earthlink.net/~cgmicro/

    ChipTools Inc   (905)274-6244   Fax: (905)891-2715
                    Email: chiptool@hookup.net
                    Web: http://www.chiptools.com/

    Circuit Cellar Inc.
                    4 Park St., Vernon, CT  06066
                    (203)875-2751   Fax: (203)872-2204

    Creative Applications Engineering, Inc
                    Ed Carryer
                    (415)494-2363   BBS: (415)494-8463

    Crossware Products
                    St John's Innovation Centre
                    Cowley Road, Cambridge, CB4 4WS, UK
                    +44 1223 421263  Fax: +44 1223 421006
                    Email: sales@crossware.com
                    Web: http://www.crossware.com

    Custom Computer Consultants
                    1807 Huron River Drive, Ypsilanti, MI 48197

    Cybernetic Micro Systems
                    Box 3000, San Gregorio, CA  94074
                    (415)726-3000

    Dallas Semiconductor
                    4401 S. Beltwood Parkway, Dallas, TX  75244-3292
                    (214)450-0448   Fax: (214)450-3715
                    International:  (214)450-5351
                    Orders:  (800)336-6933
                    Email: micro.support@dalsemi.com
                    Web: www.dalsemi.com

    DataCraft International
                    2828 Ione Dr., San Jose, CA  95132
                    (800)873-3709   (408)259-4866

    Data Sync Engineering
                    40 Trinity St., Newton, NJ 07860
                    (201)383-1355   Fax: (201)383-9382
                    Email: sales@datasynceng.com
                    Web: http://www.datasynceng.com

    DataRescue sprl
                    110 route du Condroz, 4121 Neupre  Belgium
                    Web: http://www.datarescue.com

    Dunfield Development Systems
                    P.O. Box 31044, Nepean, Ontario Canada   K2B 8S8
                    (613)256-5820   Fax: (613)256-5821
                    BBS: (613)256-6289
                    Web:   http://www.dunfield.com
                    Email: General information:      info@dunfield.com
                    Sales inquiries/Administration: sales@dunfield.com
                    Technical inquiries/Support      tech@dunfield.com
                    Old Email address:  ddunfield@bix.com

    EE Systems      50935 Hill Dr., Elkhart, IN  46514
                    (219)296-1754   Fax: (219)522-4271

    Electronic Product Design, Inc.
                    6963 Bluebelle Way, Springfield, OR  97478
                    (503)741-0778

    Embedded System Products (formerly A.T. Barrett and Associates)
                    11501 Chimney Rock, Houston, TX  77035-2900
                    (800)525-4302   (713)728-9688   Fax: (713)728-1049

    Emulation Technology, Inc.
                    2344 Walsh Avenue, Bldg. F, Santa Clara, CA  95051
                    (408)982-0660   Fax: (408)982-0664
                    Email: et@pmail.emulation.com
                    WWW: http://www.emulation.com
                    FTP: ftp.emulation.com

    Exor Inc.
                    4740T Interstate Dr., Cincinnati, OH 45246
                    (513)874-4665   Fax: (513)874-3684

    Feger + Co., Hardware + Software Verlags OHG
                    Marienstrasse 1, D-83301 Traunreut, Germany

    Forth, Inc.     1-800-55FORTH
                    http://www.earthlink.net/~forth

    Forth Systeme   P.O. Box 1103, Breisach, Germany
                    7767-551

    Franklin Software
                    (408)296-8051

    HBI Limited
                    6F, 1 Fleming Road, Hong Kong
                    852-891-3673  Fax: 852-834-9748

    Hewlett-Packard 1501 Page Mill Rd., Palo Alto, CA  94304

    HiTech Equipment Corp.
                    9400 Activity Rd., San Diego, CA  92126
                    (619)566-1892   Fax: (619)530-1458
                    Email: info@hte.com   ftp: ftp.hte.com

    Hi-Tech Software
                    PO Box 103, Alderly QLD 4051, Australia
                    (+61-7) 300 5011   Fax: (+61-7) 300 5246
                    BBS: +61 7 3300 5235
                    Email: hitech@hitech.com.au
                    WWW: http://www.hitech.com.au/

    Hitex
    North America   HiTOOLS Inc., 2055 Gateway Place, Suite 400
                    San Jose, CA 95110
                    (408) 451 3986   Fax: (408) 441 9486
                    http://www.hitex.com  info@hitex.com
    Germany         Greschbachstr 12, 76229 Karlsruhe
                    0721/9628-0      Fax: 0721/9628-149
                    info@hitex.ti.ba-karlsruhe.de
                    http://www.ba-karlsruhe.de/BA/firmen/hitex
    United Kingdom  Sir William Lyons Road, Science Park
                    Coventry CV4 7EX
                    +0203 692066     Fax: +0203 692131

    Huntsville Microsystems
                    4040 S. Memorial Parkway, PO Box 12415
                    Huntsville, AL  35802

    IAR Systems Software
    North America   One Maritime Plaza, Suite 1770
                    San Fransisco, CA 94111  USA
                    (415)765-5500   Fax: (415)765-5503
    Sweden          IAR Systems AB
                    Box 23051
                    S-750 23 Uppsala, Sweden
                    +46 18 16 7800   Fax: +46 18 16 7838
    Germany         IAR Systems GmbH
                    Brucknerstrasse 27
                    D-81677 Munchen, Germany
                    +49 89 470 6022   Fax: +49 89 470 9565
    United Kingdom  IAR Systems Ltd
                    9 Spice Court
                    Plantation Wharf, York Rd
                    London SWII 3UE, England
                    +44 71 924 3334   Fax: +44 71 924 5341

    Intel Corporation
                    3065 Bowers Ave., Santa Clara, CA  95051
                    Technical Help: (800)628-8686 (USA/Canada only)
                       5 am to 5 pm PST
                    Email: james_sampson@ccm.hf.intel.com
                    Faxback support: (800)628-2283 (USA/Canada)
                       touch tone phones only
                       Will only FAX to USA/Canada locations
                       English or Japanese support is available
                    BBS: (916)356-3600  24 Hr.
                       Auto config: 1200 thru 14.4K Baud

    Intellimap Engineering
                    1140 Morrison Dr., Suite 222
                    Ottawa Ontario Canada K2H 8S9
                    (613)829-3196   Fax: (613)820-1773

    Intermetrics Microsystems Software, Inc.
                    733 Concord Ave., Cambridge, MA  02138
                    (617)661-0072   Fax: (617)868-2843

    Iota Systems, Inc.
                    924 Incline Way, Suite N / POB 8987
                    Incline Village, NV  89452-8987
                    (702)831-6302   Fax: (702)831-4629

    Integrated Silicom Solution
                    2231 Lawson Lane, Santa Clara, CA  95054
                    (800)379-4774  Fax: (408)588-0806

    J & M Microtek, Inc.
                    83 Seaman Rd., W Orange, NJ  07052
                    (201)325-1892   Fax: (201)736-4567

    JMI Software Systems, Inc.
                    P.O. Box 481, 904 Sheble Lane, Spring House, PA 19477
                    (215)628-0840   Fax: (215)628-0353

    KC Automation GmbH (support for Sysoft products)
                    Alfredo Knecht
                    CH-6991 Neggio, Switzerland
                    Fax: ++41-91591149
                    Email: akne@tinet.ch

    Keil Elektronik GmbH
    Europe          Bretonischer Ring 15
                    D-85630 Grasbrunn b. Muenchen, Germany
                    49 89 / 46 50 57   Fax: 49 89 / 46 81 62
    North America   Keil Software
                    16990 Dallas Parkway, Suit 120, Dallas, TX  75248
                    (800)348-8051 (sales and tech support)
                    (214)735-8052   Fax: (214)735-8055
                    CompuServe: 71715,1604
                    BBS: (214)713-9883
                    Web: http://www.keil.com/
                    FTP: ftp://ftp.keil.com/

    Kontron Electronics
                    D-8057 Eching/Munich
                    Oskar von Miller Str. 1, Germany
                    (0 81 65) 77-0

    Lakeview Research (Jan Axelson)
                    2209 Winnebago St., Madison, WI  53704
                    (608)241-5824
                    Email: jaxelson@lvr.com
                    WWW: http://www.lvr.com/

    Lauterbach Datentechnik GmbH
    Europe          Fichtenstr. 27, D-85649 Hofolding, Germany
                    ++49 (0)8104 8943 31   Fax: ++49 (0)8104 8943 49
                    Compuserve: 100272,507
                    Email: sales@lauterbach.com
                    WWW: http://www.lauterbach.com
    USA             Lauterbach Inc.
                    945 Concord Street, Framingham,MA 01701
                    (508)620-4521   Fax: (508)620-4522

    Lear Com Company
                    2440 Kipling St. Suite 206, Lakewood, CO  80215
                    (303)232-2226   Fax: (303)232-8721

    Logical Systems Corporation (Disassembler, Simulator)
    Micro Dialects, Inc.
                    POB 30014, Cincinnati, OH  45230
                    (513)271-9100

    Logisoft        Box 61929, Sunnyvale CA  94086
                    (408)773-8465  Fax: (408)773-8466

    L.S. Electronic Systems Design
                    2280 Camilla Rd., Mississauga, Ontario
                    Canada  L5A 2J8
                    (905)277-4893   Fax: (905)277-0047

    Lumino B.V
                    Web: http://www.lumino.nl/lumino/

    Mandeno Granville Electronics, Ltd
                    128 Grange Rd., Auckland 3, New Zealand
                    +64 9 6300 558   Fax: +64 9 6301 720

    Matra Semiconductor
                    2840-100 San Tomas Expressway, Santa Clara, CA  95051
                    (408)986-9000

    MDL Labs
                    1073 Limberlost Court,  Columbus, OH 43235
                    Tel/Fax: 614-431-2675
                    Email: arl@infinet.com

    MetaLink Corporation
    North America   325 E. Elliot Road, Chandler, AZ  85255
                    (800)638-2423   (602)926-0797
                    Fax:  (602)926-1198
    Europe          MetaLink Europe GmbH
                    Westring 2, 8011<85614>
                    Kirchseeon-Eglharting, Germany
                    (08091)2046   Fax: (08091)2386

    Micro Computer Control Corporation
                    PO Box 275, 17 Model Ave., Hopewell, NJ  08525
                    (609)466-1751   Fax: (609)466-4116
                    BBS: (609)466-4117
                    Email: 73062.3336@compuserve.com

    Micro Future    40944 Cascado Place, Fremont, CA  94539
                    (510)657-0264   Fax: (510)657-5441
                    BBS: (510)657-5442

    MicroMint       4 Park St., Vernon, CT  06066
                    (203)875-2751   Fax: (203)872-2204

    Microtek International, Inc.
    North America   Microtek International, Inc.
                    3300 N.W. 211th Terrace, Hillsboro, OR  97124
                    (503)645-7333   Fax: (503)629-8460
    Europe          Microtek Electronics Europe GmbH
                    Starnberger Strasse 22, 82131 Gauting bei Munchen
                    Germany
                    +49(89)893139-30    Fax: +49(89)893139-50

    MPE: MicroProcessor Engineering Ltd.
                    133 Hill Lane, Shirley, Southampton SO1 5AF U.K.
                    +44 1703 631441   Fax: +44 1703 339691
                    Email: mpe@mpeltd.demon.co.uk
                           sales@mpeltd.demon.co.uk
                           70730.3576@compuserve.com

    New Micros of Dallas Texas

    Nohau Corporation
                    51 E. Campbell Ave., Campbell, CA  95008
                    (408)866-1820
                    (408)378-2912 (24 hr. information center)
                    Fax: (408)378-7869
                    Email: nohau@shell.portal.com
                    WWW: http://www.nohau.com/nohau

    Offete Enterprises, Inc.
                    1306 South B Street, San Mateo, CA  94402
                    (415) 574-8250

    Okapi Systems   (206)258-1163

    Onset Computer Corporation
                    199 Main St.,  P.O. Bos 1030
                    North Falmouth, MA 02556-1030
                    (508)563-9000   Fax: (508)563-9477

    Orion Instruments, Inc.
                    1376 Borregas Avenue, Sunnyvale, CA  94089
                    (408)747-0440  Fax: (408)747-0688
                    Email: info@oritools.com
                    http://www.oritools.com

    Orion Instruments
                    180 Independence Drive, Menlo Park, CA  94025
                    (800)729-7700   Fax: (415)327-9881

    Parallax, Inc.  6200 Desimone Lane, #69A, Citrus Heights, CA  95621
                    (916)721-8217

    Philips Microcontroller Product Group
                    811 East Arques Ave. / POB 3409
                    Sunnvale, CA  94088-3409
                    Technical documentation:
                        Sunnyvale, CA - (800)447-1500  Fax: (408)991-3773
                        Eindhoven, Netherlands - Fax: 31-40-724825
                    Technical questions:
                        Sunnyvale, CA - (408)991-3518

    Production Languages Corporation
                    P.O. Box 109, Weatherford, TX  76086
                    (800)525-6289   (817)599-8365   Fax: (817)599-5098

    Prologic Designs
                    PO Box 19026, Baltimore, MD  21204
                    (410)661-5950   Fax: (410)661-5950

    PseudoCorp      2597 Potter St., Eugene, OR 97405
                    (541)683-9173   Fax: (541)683-9186
                    Email: rhowden@teleport.com
                    Web: http://www.teleport.com/~rhowden

    Quantasm Corporation
                    19672 Stevens Creek Blvd.
                    Cupertino, CA  95014
                    (800)765-8086   (408)244-6826   Fax: (408)244-7268

    Raven Computer Systems
                    PO Box 12116, St. Paul, MN  55112
                    (612)636-0365

    Rigel Corporation
                    P.O. Box 90040, Gainesville, FL  32607

    Scientific Engineering Labs
                    255 Beacon St., Suite 3D, Somerville, MA  02143
                    (617)625-0288

    Siemens Components, Inc.
                    Integrated Circuit Division, 10950 N. Tantau Ave.
                    Cupertino, CA  95014
                    (800)777-4363  Fax: (708)296-4805

    Signetics Corporation (see Philips Microcontroller Product Group)

    Signum Systems  Mountain View, CA     (415)903-2220
                    Thousand Oaks, CA     (805)371-4608

    Software Science
                    3570 Roundbottom Rd., Cincinnati, OH  45244
                    (513)561-2060  Fax: (513)271-3181
                    Email: pbarnes@iglou.com

    Sophia Systems  NS Bldg. 2-4-1, Nishishinjuku, Shinuku-ku
                    Tokyo 160, Japan
                    03-348-7000

    Speech Technology Inc., Software Division
                    837 Front Street South, Issaquah, WA  98027
                    (206)392-8150

    SPJ Systems     114, Chitrashala Bldg.
                    562, Sadashiv Peth
                    Pune, India
                    91-212-451607   Fax: 91-212-480285
                    Email: spjs@giaspn01.vsnl.net.in
                    Web: http://www.prime-digest.w1.com/spj

    Standard Microsystems Corporation
                    80 Arkay Dr.,  Hauppage, NY  11788
                    (516)435-6000    Fax: (516)231-6004
                    WWW: http://www.smc.com
                    Email: techsupport@smc.com

    StarCom         WWW: http://www.n2.net/starcom

    Sun Equipment Corporation
    Lodestar Electronics Corp.
                    616 Hawick Rd., Raleigh, NC  27615
                    (800)870-1955   (919)881-2141   Fax: (919)870-5720

    Suncoast Technologies
                    P.O. Box 5835, Spring Hill FL 34606
                    Voice/FAX (352)596-7599
                    Email: suncoast@earthlink.net
                    WWW: http://home.earthlink.net/~suncoast/

    Sysoft SA       (closed as of 1989 - see KC Automation GmbH)

    Systronix Inc.  555 S. 300 E., Salt Lake City, UT  84111
                    (801)534-1017  Fax: (801)534-1019
                    BBS: (801)487-2778

    TCG
                    11 Ally22 Ln21 Pei-Ta Rd.
                    Hsin-Chu City, Taiwan, R.O.C.
                    (886)3-532-7372   Fax: 886-3-531-7162
                    Email:ch.bbs@csie.nctu.edu.tw
                    http://www.yp.at-taiwan.com/~com00121
                    http://www.hth.com

    URDA, Inc.      (800)338-0517   (412)683-8732

    US Software     14215 N.W. Science Park Drive, Portland, OR  97229
                    (800)356-7097   (503)641-8446   Fax: (503)644-2413
                    Product information available by ftp -
                       ftp.netcom.com : pub/ussw

    Universal Cross Assemblers
                    Canada
                    (506)849-8952   Fax: (506)847-0681

    Vail Silicon Tools, Inc.
                    Box 165, Pompano Beach FL  33069
                    (305)491-7443   Fax: (305)974-8531

    Xicor
                    1511 Buckeye Dr., Milpitas, CA
                    (408)432-8888   Fax: (408)432-0640
                    Email: info@smtpgat.xicor.com
                    http//www.xicor.com
                    BBS: (800)258-8864

    Zax Corporation
                    2572 White Road, Irving, CA 92714
                    (800)421-0982   (714)474-1170

    Zitek Corporation
                    1651 East Edinger Ave., Santa Ana, Ca  92705
                    (714)541-2931


5)  8051 DOCUMENTATION


5.1) Periodicals that cover the 8051

    Various magazines and journals (journals seems to be THE popular name
    for magazines these days) provide articles from time to time on the
    8051 family of microcontrollers:

    The Computer Applications Journal (Circuit Cellar Ink)
        - programming and construction articles
        - POB 7694, Riverton, NJ  08077-8784
        - FAX: (203)872-2204
        - Voice orders: (609)786-0409
        - Email orders: ken.davidson@circellar.com
        - BBS: (203)871-1988
          WWW: http://www.circellar.com
        - $21.95, $31.95 surface Canada and Mexico,
          $49.95 air all other countries

    Computer Design
        - industry announcements and trends
        - One Technology Park Drive, P.O. Box 990, Westford, MA  01886
        - (508)692-0700

    The Computer Journal
        - programming and construction articles, specializing in 8-bit
          and older computers (Z80-CP/M, TRS-80, Xerox, microcontrollers,
          etc)
        - programming and construction articles, specializing in old
          computers (S-100, CP/M, TRS-80, Xerox, Adam, etc)
        - P.O. Box 3900, Citrus Heights, CA 95611-3900
        - (800)424-8825 or (916) 722-4970   FAX: (916) 722-7480
        - BBS: (916) 722-5799
        - Web: http://www.psyber.com/~tcj
        - Email: tcj@psyber.com
                 Dave Baldwin: dibald@netcom.com
                 Bill Kibler: kibler@psyber.com
        - USENET newsgroup alt.tcj

    Dr. Dobbs Journal
        - programming articles, concepts, and designs
        - 411 Borel Ave., San Mateo, CA  94402
        - (415)358-9500

    EDN
        - Cahners Publishing Company
          8773 South Ridgeline Blvd., Highlands Ranch, CO 80126-2329
        - annual microprocessor and DSP editions
        - http://www.ednmag.com/

    Electronic Engineering Times
        - industry announcements and trends
        - FREE to qualified engineers and managers involved in
          engineering decisions
        - Fulfillment Dept., PO Box 9055, Jericho, NY  11753-8955
        - FAX: (516)733-6960

    Electronics Now
        - construction articles
        - Box 55115, Boulder, CO  80321-5115
        - $19.97 one year

    Elektor Electronics
        - programming and construction articles
        - World Wide Subscription Service Ltd
          Unit 4, Gibbs Reed Farm, Pashley Road
          Ticehurst TN5 7HE, England
        - 27 UK pounds
     or
        - Old Colony Sound Lab, P.O. Box 243, Peterborough, NH 03458
        - Tel. (603)924-6371, 924-6526
        - Fax: (603)924-9467
        - $57 USA and Canada per year

    Embedded Systems Programming
        - programming and systems design articles
        - Miller Freeman Publications
        - 500 Howard St., San Francisco, CA  94105
        - Miller Freeman: (415)905-2200
        - Embedded Systems Programming phone: (800)829-5537

    Forth Dimensions
        - monthly magazine on Forth
        - Forth Interest Group, P.O. Box 2154, Oakland, California 94621
        - (510)893-6784   Fax: (510)535-1295
        - Email: johnhall@aol.com
        - Forth Interest Group home page:
             http://taygeta.oc.nps.navy.mil/fig_home.html

    Inquisitor Magazine
        - If you're the type that watched Gilligan's Island for its
          socio-political insights, then you'll love a new 'zine that
          just crossed my desk - Inquisitor Magazine.  It's general
          philosophy seems to be ... well, it seems to be ... uh, yeah!
          Technical in nature, bizarre, tongue in cheek, eclectic,
          electric, did I mention bizarre(?), and lots of fun.  Worth
          looking at if you like the out of the ordinary.  The moving
          force behind this magazine is Daniel Drennan, who seems to have
          suffered from an overdose of radiation from his computer
          monitor ;-).
        - Dan is offering issue 1 of Inquisitor for free except for
          postage ($1.00 in the United States; $2.00 for Canada and
          overseas surface mail; and $3.00 for overseas airmail).  This
          issue contains plans, schematics, and troubleshooting tips for
          putting together a 8052-based microcontroller.  If you're
          thinking of putting together an 8051 system, you might want to
          check this out.
        - Planetarium Station, P.O.Box 132, New York, NY  10024-0132
        - (212)595-8370
        - Email: inquisitor@echonyc.com
        - $16 per year (4 issues)

    Microcomputer Journal
        - programming and construction articles
        - Midnight Engineering, 1700 Washington Av., Rocky Ford, CO 81067
        - (719)254-4558  Fax: (719)254-4517

    Midnight Engineering
        - 1700 Washington Ave., Rocky Road, CO  81067
          (719)254-4558   Fax: (719)254-4517

    MW Media - Product Directories
        - 8051 Product Directory
          (survey of various 8051 products)
        - Intel Development Tools Handbook
          (survey of commercial development tools for the 8051, 8096,
          and 80186 lines of Intel microprocessors)
        - This documents could very well be a "must" if you're into
          serious development using one of these chips.  If you are
          "just" a hobbyist, see how the "other half" lives.
        - other guides on Intel development tools, Embedded Intel 386,
          Intel 486/Pentium, 8051 products, Hitachi microcontroller
          development tools, AMD FusionE86, AMD 29K; low power products,
          DSP, multimedia CD
        - FREE to qualified developers
        - MW Media
        - Fairmont Plaza, 50 W. San Fernando, #675, San Jose, CA  95113
        - (408)288-4721 and (408)286-4200
        - FAX: (408)288-4728

    Nuts & Volts Magazine
        - A National Publication for the Buying and Selling of
          Electronic Equipment
        - 430 Princeland Court, Corona, CA  91719
        - Mailed third class, USA only:  $17.00 one year
                                         $31.00 two years
        - Mailed first class, one year only:  $34.00-USA
                                              $35.00-Canada/Mexico
        - Foreign/Air Mail - $70.00;  Foreign/Surface - $39.00
        - (800)783-4624
        - Email:  74262.3664@compuserve.com


5.2)  Books on the 8051

5.2.1)  List of books

    I don't have information on all of these, only that they exist.  I
    would greatly appreciate it if someone could provide a short synopsis
    and the complete book name if you are familiar with any of these
    titles.



    The 8051 Family of Microcontrollers
        - Richard H. Barnett
        - Prentice-Hall, 1995
        - ISBN 0-02-306281-9

    8051 Interfacing and Applications
        - Applied Logic Engineering
        - 13008 93rd Place North, Maple Grove, MN  55369
        - (612)494-3704

    The 8051 Microcontroller
        - I. Scott MacKenzie
        - Prentice Hall
        - 2nd edition, 1995
        - ISBN 0-02-373660-7
        - includes schematics for a single-board computer,
          assembly-language source code for a monitor program, and
          interfaces to a keypad, LEDs, and loudspeaker

    The 8051 Microcontroller
        - James W. Stewart
        - Regents/Prentice-Hall, 1993
        - $27.50, 273 pages
        - includes many interfacing examples (switches, solenoids,
          relays, shaft encoders, displays, motors, and A/D converters)
          and a chapter on top-down design method

    The 8051 Microcontroller: Architecture, Programming and Applications
        - Kenneth J. Ayala
        - 241 pages, soft cover
        - 5.25" diskette with assembler and simulator
        - ISBN 0-314-77278-2, Dewey 004.165-dc20
        - West Publishing Company
        - P.O. Box 64526, St. Paul, MN  55164
        - (800)328-9352
        - see review in next section

    Assembly Language Programming (for the MCS-51 family)
        - F. A. Lyn
        - L. S. Electronic Systems Design

    Basic-52 Programmer's Guide
        - Systronix, Inc. (they also sell a Basic compiler)

    Beginner's Guide
        - Suncoast Technologies

    C and the 8051
        - Thomas W. Schultz
        - Prentice Hall
        - ISBN 0-13-753815-4

    Data book / Handbook / Users' Guide
        - Advanced Micro Devices
        - Dallas (User's guide for the DS5000)
        - Intel
        - Philips
        - Siemens

    Embedded Controller Forth for the 8051 Family
        - Academic Press (I think)
        - William H. Payne
        - uses a Forth development system available on the Internet
          (see above in the Forth software section)

    Embedded Systems Programming in C and Assembler
        - John Forrest Brown
        - Van Nostrand Reinhold, 1994
        - 304 pages, $49.95
        - ISBN 0-442-01817-7
        - covers Motorola and Intel processors
        - includes diskette with code from the book
        - book review in Dr. Dobb's Journal, November 1994, page 121

    Experimenter's guide
        - Rigel Corporation

    Flow Design for Embedded Systems
        - Barry Kauler
        - R&D Books / Miller Freeman (USA), 1997
          distributed in Europe by McGraw-Hill
        - ISBN 0-87930-469-3
        - http://www.rdbooks.com/
        - bundled with a sophisticated graphical diagrammer and CASE
          tool, K-Flow diagrammer, that runs on Windows 3.1 or 95
        - source code for the TERSE RTOS is supplied

    Introduction to Microcontroller Design, Based on the 8051 family of
    Processors
        - Business Data Computers
        - P.O. Box 1549, Chester, CA  96020

    The Microcontroller Idea Book
        - Jan Axelson (of Microcomputer Journal fame)
        - features the 8052-BASIC microcontroller
        - hands-on guide with complete plans (schematics, design theory,
          program listings, construction details, etc)
        - explains how to use sensors, relays, displays, clock/calendars,
          keypads, wireless links, and more
        - 1994, 273 pages, $31.95 + shipping
        - Lakeview Research, 2209 Winnebago St., Madison, WI  53704
          (608)241-5824
        - contact the author at jaxelson@lvr.com
        - WWW: http://www.lvr.com/
        - Lakeview Research's microcontroller page (resources for
          8052-Basic projects): http://www.lvr.com/microc.htm

    Programming and Interfacing the 8051 Microcontroller
        - Sencer Yeralan and Ashutosh Ahluwalia
        - wealth of information, including: 8051 architecture,
          programming basics and techniques, on-chip features, building
          your own 8051 system, and interfacing to various peripherals
        - hardware experiments contains plans and code for:  scanning a
          keypad, stepper motor control, a frequency generator, measuring
          light and temperature intensity (analog to digital), digital to
          analog conversion, DC motor speed regulation, interfacing to
          intelligent Liquid Crystal Displays, and implementing a
          multi-drop RS-485 network
        - accompanying diskette has an 8051 simulator and all source code
          for the projects in the book
        - must have book for the hobbyist or professional
        - $34.38, 352 pages, paperback, ISBN 0-201-63365-5
        - Addison-Wesley


5.2.2)  Book reviews

    My review of the book:
    Programming and Interfacing the 8051 Microcontroller
    by Sencer Yeralan and Ashutosh Ahluwalia

       Addison-Wesley has just released a GREAT new book, "Programming
       and Interfacing the 8051 Microcontroller" by Sencer Yeralan and
       Ashutosh Ahluwalia.  I had actually reviewed the manuscript some
       time back, and the book has now finally been released.  This book
       contains a wealth of information - it answers a lot of Frequently
       Asked Questions that often appear in comp.robotics,
       sci.electronics, and comp.arch.embedded.

       Among the some of the basic subjects covered include: 8051
       architecture, programming basics and techniques, on-chip features,
       building your own 8051 system, and interfacing to various
       peripherals.  A section on hardware experiments contains plans and
       code for:  scanning a keypad, stepper motor control, a frequency
       generator, measuring light and temperature intensity (analog to
       digital), digital to analog conversion, DC motor speed regulation,
       interfacing to intelligent Liquid Crystal Displays, and
       implementing a multi-drop RS-485 network.

       The book comes with a diskette containing an 8051 simulator and
       all source code for the projects in the book.  This is a must have
       book for the hobbyist or professional.  Available for $34.38, 352
       pages, paperback, ISBN 0-201-63365-5.  Run, don't walk, to your
       bookstore and get one now.  I mean it, this is a great book.


    My review of the book:
    The Microcontroller Idea Book
    by Jan Axelson

       This book is loosely based on a series of articles Jan wrote for
       ComputerCraft magazine (now the Microcomputer Journal).  If you
       are at all familiar with her work, you already realize that you're
       wasting your time by reading this review and you might as well
       just order your copy now.

       This is an excellent book for hobbyists and tinkerers, as it
       includes complete circuit schematics and parts lists, design
       theory, example program listings, construction and debugging tips,
       and vendor listings.  The example circuits and programs are based
       on the 8052-BASIC chip (a favorite with hobbyists due to its ease
       of use), and there is a lot of material on programming in BASIC52.
       The book is [very] useful even if you use a standard 8051 part.
       Lots of different interfacing ideas including: sensors, motors,
       LEDs, LCDs, wireless links, and a LOT more.

       Chapter titles:  microcontroller basics, inside the 8052-
       BASIC, powering up, saving programs, programming, inputs and
       outputs, switches and keypads, displays, using sensors to
       detect and measure, clocks and calendars, control circuits,
       wireless links, calling assembly-language routines, running
       BASIC-52 from external memory, related products

       If you are just starting out with microcontrollers, and don't have
       a clue where to start or what to control, this book is just what
       you need.  As the title of the book says, it's an idea book.

            The Microcontroller Idea Book
            Jan Axelson
            1994, 273 pages, $31.95 + shipping
            Lakeview Research, 2209 Winnebago St., Madison, WI  53704
               (608)241-5824
               Email: jaxelson@lvr.com
               Web: http://www.lvr.com/


    My review of the book:
    The 8051 Family of Microcontrollers
    by Richard H. Barnett

       This book VERY thoroughly discusses the design and implementation
       of controllers using the 8051.  Dick says his book is "lots of
       meat, very little filler", but he's a bit off the mark here.  What
       he means to say is this book is many large chunks of meat, no
       vegetables, and no potatoes - we are NOT talking Hamburger Helper
       here gang.  The introduction alone contains circuits for 3
       controllers (one 8085 design used as a comparison).  Many hardware
       and softare examples are included.  Everywhere you turn in this
       book, you'll find circuit diagrams and sample code, including
       complete designs for three different microcontroller projects in
       the last chapter.  Clear and in-depth coverage of interfacing and
       peripheral use leaves very little to the imagination.

       This is a good book for both students and professionals who are
       trying to figure out how to start designing there own
       microcontroller.  Experienced hobbyists will also appreciate the
       many examples.  Novices might be a bit overwhelmed by this book.

            The 8051 Family of Microcontrollers
            Richard H. Barnett
            Prentice-Hall, 1995
            ISBN 0-02-306281-9

       For more info contact the author - rbarnett@purdue.edu


    Richard Kendrick's review of the book:
    8051 Interfacing and Applications
    from Applied Logic Engineering

       IN BRIEF

       An excellent collection of interfacing circuits and well commented
       source code in assembly.  This is not a book for beginners as it
       assumes the user is very familiar with the architecture of the
       8051 and its registers.  A disk of assembly source code listings
       is included.

       CHAPTERS

             1    - 8051 Interfacing and Applications
             1.1  - Introduction
             1.2  - Main System Core
             1.3  - Simple Methods of User Input
             1.4  - Interfacing a 16 digit keypad to the 8031
             1.5  - Centronics Parallel Input Port
             1.6  - Centronics Parallel Output Port
             1.7  - Interfacing to the built-in Serial Port
             1.8  - Interfacing to a Dual Channel UART
             1.9  - Interfacing to an LCD
             1.10 - Bank Selection of Memory
                  - Appendix A: List of Vendors
                  - Appendix B: Connection to an External Computer
                     0.1 RS-232 Serial Connection
                     0.2 Centronics Interface Cabling

       COMMENTS

       This spiral bound book is thin (74 pages) but manages to cover a
       lot of information.  All of the sub-chapters have excellent code
       listings with full comments, partial schematic diagrams, and an
       occasional timing diagram.  The chapter on using the serial port
       is based on the MAX232 chip becoming so popular.  A table of timer
       reload values is provided to get standard baud rates but the book
       only mentions the required clock frequency of 11.0592 mHz in the
       first chapter.  It also doesn't explain why a seemingly
       non-standard crystal frequency was chosen.  The dual UART channel
       features the 2681 chip.  The LCD chapter gives a small but
       adequate explaination of the Hitachi controller chip usage on LCD
       displays and a tiny fragment of data on display characteristics of
       LCDs.  The bank selection of memory is useful showing code and
       schematic using five 62256 chips for 160K bytes of read/write
       memory.


    Richard Kendrick's review of the book:
    Microprocessor/Controller Design
    by Wayne P. Lichti of Business Data Computers

       A lame little book better bypassed.  As an introductory text,
       Kenneth Ayala's book is the winner hands down.  This book is a
       poor rehash of the same information in Intel's or AMD's data book.
       There is one code listing in the book and does little more than
       tell the reader that the 8051 family of processors exist.

       This book is 134 pages of wasted time.  The schematics were
       printed on a dot matrix printer and poorly reproduced.  Many of
       the sections are just a table or a paragraph with two or three
       sentences.  Use Ayala's book, you'll learn a lot more useful
       information.


    John Little's review of the book:
    The 8051 Microcontroller: Architecture, Programming and Applications
    by Kenneth J. Ayala

       IN BRIEF

       A good book for those who are already moderately familiar with
       assembly language programming and wish to learn more about 8051
       specifics.  Has many example listings, all of which are very well
       documented in terms of comments and explanations in the text. NOT
       a book for absolute beginners OR hardware hackers looking for
       circuits and applications.


       CHAPTERS

          1 - Microprocessors and Microcontrollers.
          2 - The 8051 Architecture.
          3 - Moving Data.
          4 - Logical Operations.
          5 - Arithmetic Operations.
          6 - Jump and Call Opcodes.
          7 - An 8051 Microcontroller Design.
          8 - Applications.
          9 - Serial Data Communication.
          A - 8051 Operational Code Mnemonics.
          B - How to Use the Assembler.
          C - how to Use the Simulator.
          D - The 8255 Programmable I/O Port.
          E - Control Registers.


       COMMENTS

       In his preface to the book, Mr Ayala states that that it is
       intended for "... a diverse audience. It is meant for use
       primarily by those who work in the area of electronic design and
       assembly language programming of small, dedicated computers".
       Later, he goes on to refer the reader to the manufacturer's data
       books for more information on hardware issues. This sets the tone
       for the whole book, which is very much software orientated.

       Anyone buying the book expecting to find reams of circuit diagrams
       and details on how to build their own 8051 driven, automated car
       assembly plant will be disappointed. In fact, most of the circuits
       and applications shown are very much conceptual, with generic,
       black-box outlines for most of the components. The single
       exception to this is a fairly complete system (8031, EPROM & RAM,
       jumper selectable memory sizes) in the chapter on microcontroller
       design.  Even then, there's no I/O shown (the txd/rxd are
       unconnected).

       Having said that, Mr Ayala does do a fairly thorough job of
       working through the peculiarities of the 8051, with detailed
       coverage of memory organisation, bit/byte level operations,
       timers, interrupts and, at the end of the book, a complete chapter
       on 8051 communication modes. Each area has relevant assembly
       language listings, along with a detailed explanation of the
       workings of the code.

       Each section also has highlighted "comment" passages which point
       out common pitfalls and reinforce critical points. Each chapter
       ends with a summary of the important points covered and a series
       of ten to twenty pertinent problems for the reader to solve. For
       the most part, the answers to the problems can be found in the
       text.  In later chapters though, the reader is asked to elaborate
       on various programming themes and to write assembly language
       programs of their own to perform various tasks. The problems range
       from the bland "Name twenty items which have a built in
       microcontroller" (Chapter 1), to the more esoteric "Compose a
       40-value lookup table that will generate a sawtooth wave using a
       D/A converter" (Chapter 8).

       It should be noted that the book is not aimed at the complete
       novice. For instance, although assembly language listings are used
       throughout, it is not until Appendix B that the reader finds out
       what the assembler actually does and how the listings relate to
       machine code. Even then, the complete neophyte will be left with a
       rather empty feeling, as there are pages and pages of code, the
       schematic for a (more or less) complete system and instructions on
       how to use the assembler, but no information at all on how the
       object code should be utilised (other than with the included
       simulator - see below). If you don't already know how to blow an
       EPROM, you're in trouble.

       The diskette which accompanies the book contains the PseudoSam
       assembler (which is used throughout) and an 8051 simulator. Both
       being intended for use on a PC (it's a measure of how fast the
       computer industry is evolving that a 5.25 inch diskette seems a
       little archaic just three years after the publication date of the
       book).  The PseudoSam assembler ran fine on my system and I was
       able to assemble several of the examples from the book and
       successfully run them on a small, home-brew 8031 system. I was
       totally unable to get the simulator to run. However, as it failed
       on several different systems I'm prepared to believe that my
       particular copy of the diskette was at fault.


       SUMMARY

       All in all, a recommended book for those who have previous
       assembly language experience and wish to get to know details
       relating to the 8051 microcontroller. While the internal
       architecture of the chip is covered in detail, external hardware
       and peripheral interfacing is not.  Only the basic 8051/31 is
       covered, with little mention of the other variants available.
       There are extensive listings in the text, covering routines for
       handling keyboards and displays, as well as timing loops and
       communications. A large, clear typeface ensures that all of the
       listings are completely legible. The layout and presentation of
       the book is excellent, with a consistent, unambiguous style used
       throughout.


    Tim McDonough's review of the book:
    C and the 8051: Programming for Multitasking
    by Thomas W. Schultz

       Schultz's book provides a brief overview of the 8051 architecture
       but is primarily a discussion of multi-tasking software in an 8051
       environment.  He presents quite a few code examples.  The examples
       and the accompanying text show comparisons of how to accomplish
       things in assembler, PLM, and C.  The C examples presented are
       based on Version 3 of the Franklin compiler but should be easily
       understandable by anyone already familiar with C.

       Later chapters in the book deal with more advanced topics.
       Chapters are devoted to Real-Time Ideas, Timing and Scheduling,
       Communications and Synchronization, Interrupts, Priority, and
       Context, and Distributed Systems.  The Real-Time Ideas chapter
       briefly discusses six Real Time Operating System (RTOS) kernels
       offered by several vendors.  Later in the book some examples are
       given to simple applications with and without using a RTOS.

       All in all, a useful addition to my technical library.  It is one
       of the few 8051 books that goes beyond the basics and would be
       particularly of interest to those contemplating their first
       non-trivial 8051 design.


    My review of the book:
    Basic-52 Programming
    by Bruce Boyes, Will Bagley, and Scott Kendall of Systronix, Inc.

       A must have book for Basic-52 programmers.  The book starts out
       with an introduction to BASIC-52 programming, program editing, and
       techniques.  About a hundred of the book's 160 pages are a
       detailed and quite useful reference of the commands and
       statements.  Six appendixes covering advanced topics round out
       this most useful volume.  A quick index to commands, operators,
       and instructions printed on the back cover of the book is a nice
       finishing touch.  For only $20.00, it's a bargain at twice the
       price.  Well, let's not get carried away, but if you're
       programming in Basic-52, this book is indispensible.


5.3)  Miscellaneous documentation on the 8051

    Advanced Micro Devices
        - application notes

    Intel Corporation
        - application notes

    L.S. Electronic Systems Design
        - application notes (source code on diskette and schematics)

    Philips Semiconductors (Signetics)
        - application notes

    Software Science
        - application notes


__________________________________________________________

I disclaim everything.  The contents of this article might be totally
inaccurate, inappropriate, misguided, or otherwise perverse - except for
my name (hopefully I got that right).

Copyright (c) 1997 by Russ Hersch, all rights reserved.
This FAQ may be posted to any USENET newsgroup, on-line service, or BBS
  as long as it is posted in its entirety and includes this copyright
  statement.
This FAQ may not be distributed for financial gain.
This FAQ may not be included in commercial collections or compilations
   without express permission from the author.

-----------------------------------
Russ Hersch - russ@shani.net

User Contributions:

Comment about this article, ask questions, or add new information about this topic:

CAPTCHA


[ Usenet FAQs | Web FAQs | Documents | RFC Index ]

Send corrections/additions to the FAQ Maintainer:
russ@shani.net (Russ Hersch)





Last Update March 27 2014 @ 02:11 PM