Major contributors to this section: Glenn M. Saunders, Tomasz M. Tatar,
James Bradford, Konrad M. Kokoszkiewicz, Don Schoengarth, Andreas
Koch, TXG/MNX

SD=Single-Density, 90K/disk side
ED=Enhanced-Density, 130K/disk side
DD=Double-Density, 180K/disk side

SS=Single-Sided (drive has only one drive head, so it can only read/write to
                 one side of the disk.  The reverse side of a 2-sided "flippy"
                 disk may be used by inserting the disk upside-down.)
DS=Double-Sided (one of 3 possible data-mappings, see below for details)

Printer port=has a standard DB25 parallel printer port,+ maybe a print buffer
Master=includes drive controller, can add additional,non-Atari-specific drives

Top transfer rate is 19.2Kbps unless stated otherwise.

Floppy disk drives designed for the 8-bit Atari computers:
Atari 810            SS SD
Atari 1050           SS SD/ED
Atari XF551          DS SD/ED/DD, 38.4Kbps burst mode
Access Unlimited ATAR88-1
                     SS SD master
Access Unlimited ATAR40-1
                     SS SD/DD master
Amdek AMDC I         SS SD/DD uses "flippy" Amdisk III 3" disk/carts,
                     printer port, master
Amdek AMDC II        SS SD/DD dual drives, printer port, master
AS SN-360            DS SD/ED/DD
Astra 1001           SS SD/DD, printer port
Astra 1620           SS SD/DD dual drives
Astra 2001           SS SD/DD dual drives
Astra Big-D          DS SD/DD dual drives
Astra The "One"      DS SD/DD, printer port
B&C 810              SS SD, optional Happy Warp Speed 52Kbps
Concorde C-221M      SS SD/DD master
Concorde C-222M      DS SD/DD master
CSS Floppy Board, for the Black Box, master, support PC 720K and 1.44MB 3.5"
                     drives, support PC 1.2MB and 360kB 5.25" drives,
                     also read/write 5.25" and 3.5" MS-DOS disks
                     see: http://www.nleaudio.com/css/products/floppy.htm
Flop Roznov pod Radhostem VD 40 F
                     SS SS/ED/DD, XF551 compatible, printer port
                see: http://www.atariage.com/forums/index.php?showtopic=99716
High-Density Disk Interface (HDI) by Erhard Puetz. a PCB, master
                     connect up to 4 standard PC high-density drives
Indus GT             SS SD/ED/DD, Synchromesh mode usable with SpartaDOS X
                     and DOS XL only.
                     72Kbps under SpartaDOS X, 37Kbps under DOS XL. Z-80 cpu
                     option: RAM-Charger 64K RAM + software, for CP/M support
Karin Maxi           PBI/ECI device, master, WD1772 + 2KB driver ROM
                     DS formats use PC-standard 'head-first' mapping
L.E. Systems LEDS5-01
                     SS SD/DD master, 134.4Kbps, 800 only
                     CP/M expansion: 4MHz Z80, 64K RAM
L.E. Systems LEFDC-04
                     SS SD Four drives, copies a disk in 22 secs, 800 only
L.E. Systems LEFDC-08
                     SS SD Eight drives, copies a disk in 22 secs, 800 only
LDW Super 2000       SS SD/DD, 19.2Kbps or 67Kbps. Indus GT clone
                     "Logical Design Works"
   image: http://membres.lycos.fr/romualdl/images/atari/super2000.jpg
LDW/California Access CA-2001
                     SS SD/DD, 19.2Kbps or 38.4Kbps
                     Indus GT/LDW Super 2000 clone
   image: http://membres.lycos.fr/romualdl/images/atari/ca2001.jpg
LDW/California Access CA-2002
                     DS SD/ED/DD,19.2Kbps,70Kbps w/SpartaDOS
Micro MainFrame MF-1681
                     SS SD/DD, printer port, 4K to 54K printer buffer,
                     hard disk firmware included, master, Z-80 CPU w/ 16K to
                     64K RAM for CP/M, TRSDOS, MaxiDOS A, and OASIS.
Micro MainFrame MF-1682
                     dual drives version of MF-1681
Percom RFD40-S1      SS SD/DD, master
Percom RFD40-S2      SS SD/DD dual drives, master
Percom RFD44-S1      DS SD/DD, master
Percom RFD44-S2      DS SD/DD dual drives, master
                     (80-track RFDs hinted at
                     http://www.atarimagazines.com/v1n2/newproducts.html)
Percom AT88          SS SD, master
Percom AT88-S1PD     SS SD/DD, printer port, master
Percom AT88-S2PD     SS SD/DD dual drives, printer port, master
Rana 1000            SS SD/ED/DD, stand alone disk formatting
RCP 810              SS SD
San Jose Computer Special Edition 810
                     SS SD, optional Happy Warp Speed 52Kbps
Spider               SS SS/ED/DD,XF551 compat,printer port,only 70 protos made
                see: http://www.atariage.com/forums/index.php?showtopic=99716
SWP ATR8000          4MHz Z80, 16K RAM, RS-232, master, printer port
               or    4MHz Z80, 64K RAM, RS-232, master, printer port, CP/M 2.2
                     options:  128K or 256K CO-POWER-88 with MS-DOS; CP/M-86
TOMS 720             DS SD/ED/DD/ID/QD/ST
                     printer port, MYDOS 4.5 on ROM, 68.2Kbps
                     Intel 8085 microprocessor
                     SS/SD - 40 tracks, 18 sectors, 128 bytes/sector = 90 kB
                     SS/ED - 40 tracks, 26 sectors, 128 bytes/sector = 130 kB
                     SS/DD - 40 tracks, 18 sectors, 256 bytes/sector = 180 kB
                     SS/ID - IBM S-9 - 40 tr, 9 sc, 512 bytes/sector = 180 kB
                     DS/DD - 40 tracks, 18 sectors, 256 bytes/sector = 360 kB
                     DS/QD - 80 tracks, 18 sectors, 256 bytes/sector = 720 kB
                     DS/ID - IBM D-9 - 40 tr, 9 sc, 512 bytes/sector = 360 kB
                     DS/ST - Atari ST - 80 tr, 9 s, 512 bytes/sector = 720 kB
                     1050 Turbo speed and UltraSpeed
                     Optional RS-232 port
TOMS 710             features same as TOMS 720, plus:
                     - also has TOMS Navigator (like Norton Commander) on ROM
TOMS 360             features same as TOMS 720, except:
                     - no support for 720K formats
Trak AT-1            SS SD/DD master.upgrade: printer port+4K/16K buffer
Trak AT-D1           SS SD master, printer port, 4K print buffer.upgrade:16K
Trak AT-D2           SS SD/DD master, printer port, 4K printbuffer.upgrade:16K
Trak AT-D4           DS SD/DD, printer port, print buffer
Trak Champ           SS SD master
Trak Champ2          SS SD/DD master
Trak AT-S1           SS SD/DD slave
Viatronic Brno VD 40 SS SS/ED/DD, XF551 compatible, printer port
XFD601 (Jacek Zuk)   DS SD/ED/DD 70kbps,Top Drive,Synchromesh,UltraSpeed,
                     XF551 compat.
                     http://atariki.krap.pl/index.php/XFD601
XFD602 (Jacek Zuk)   DS SD/ED/DD dual drives,70kbps,Top Drive,Synchromesh,
                     UltraSpeed,XF551 compat
                     XF clones with indus GT speed, but have a FAST and TURBO
                     mode. The Fast mode is the same a INDUS GT and turbo is
                     also INDUS GT only works with SpartaDOS X. There is a
                     jumper for Fast/Turbo.
                see: http://www.atariage.com/forums/index.php?showtopic=113924
                 or: http://atariki.krap.pl/index.php/XFD602

While any standard "slave" drive will work with "master" drives listed above,
the following are slave drives marketed specifically to Atari users:
Access Unlimited ATAR88-A1 SS SD slave
Access Unlimited ATAR40-A1 SS SD/DD slave
Concorde C-221S      SS SD/DD slave
Concorde C-222S      DS SD/DD slave
Percom RFD40-A1      SS SD/DD slave
Percom AT88-A1       SS SD/DD slave
RCP 100              DS SD/DD, slave
RCP 200              DS SD/DD dual drives, slave

The following information is taken from the documentation for HiassofT's
WriteAtr program, http://www.horus.com/~hias/atari/

Double-Sided drives for the Atari may use one of three different drive-
mapping possibilities.
   * Most double-sided Atari disk drives:
     First fill tracks 0-39 (or 0-79) on the first side, then switch
     over to side 2 and again fill tracks 0-39 (0-79 for 3.5" disks).

   * The XF551 first fills track 0 on the first side. Then it
     fills track 1, then track 2, ... up to track 39 (on a 5.25" disk)
     or 79 (on a 3.5" disk). Then it switches to side 2 and fills
     the disk in reverse order (starting at track 39/79, then 38/78,
     ... til it has reached the end of the disk at track 0).

   * The third possibility is the standard in the PC world, but on the Atari
     it's possibly unique to drives connected via the Karin Maxi interface.
     If your Atari disk drive uses this mapping, it first fills
     track 0 on side 1, then track 0 on side 2, then seeks to track 1,
     again first fills track 1 / side 1, then track 1 / side 2,
     and so on, until it finishes with track 39 (79) / side 2.
     The drive switches the heads (sides) first before switching
     the track.