Atom IDE for Sam Coupé

Atom is an interface for IDE devices, usually internal. Allows to connect harddisk or CD reader. Supported by B-DOS, CPM22QED and ZXVGS.

Purposes

• Connecting hard disk or CD reader.
• Using CPM22QED or ZXVGS with hard disk.
• Viewing animations prepared with BMP2SCR.

Properties

• Multiplexes between 16bit IDE bus and 8bit Z80 bus.

Mounting

• In the slot of the right hand disk drive.
• 40 wires flat cable connects the interface and IDE device.
• Extra power supply is needed for the IDE device, unless it is 2.5" disk or Compact Flash.

Signals on floppy drive slot

In floppy drive slot are ony signals /WR and /DISC, which includes address decoding with /IORQ=0. The /RD signal of Z80CPU is not connected and must be regenerated. The problem is, the /WR=0 signal appears before /DISC=0 and faster disappears. Using a stndard decoder it may happen, there is /WR=1, but still is /DISC=0 - what means port reading as small pitch (hazard). Thanks to 74LS137 latch the /F5WR=0 signal is until /DISC=1 and no /F5RD=0 appears. This is shown on the picture below.

Files for download

atom009.jpg 76.3kB (2006-11-01 21:52)

Two v009 mounted, one at bottom, one at top view.

samtop.jpg 36.0kB (2005-03-03 17:18)

My unassembled Sam with Atom, 8250 serial and Maxtor 7120AT (124MB). Top view.

samside.jpg 38.3kB (2005-03-03 17:17)

My unassembled Sam with Atom, 8250 serial and Maxtor 7120AT (124MB). Side view, some garbage in backplane.

atom006.jpg 100.9kB (2005-01-21 19:31)

Mounted v006 top and bottom view.

atom007b.png 23.6kB (2004-01-30 04:09)

Board v007 picture from Eagle.

atom007s.png 44.3kB (2004-01-30 04:06)

Board v007 schematics from Eagle.

atom-007.zip 42.8kB (2003-08-26 14:02)

PCB v007 data files for Eagle.

atom-006.zip 39.5kB (2003-07-07 15:27)

(old) PCB v006 data files for Eagle. Missed transistor inverter near 74*137 decoder.

atom-002.zip 22.9kB (2003-07-01 19:37)

(old) PCB v002 data files for MaxonPLP and Eagle. First prototype. Chips are too close to each other and to the slot.

atom002e.jpg 96.3kB (2003-06-13 22:30)

Mounted v002 top view. First prototype with 74LS138.

atom002l.jpg 79.2kB (2003-06-13 22:41)

Mounted v002 bottom view.

hdb_rom.zip 26.9kB (2002-10-12 03:10)

Boot ROM for Sam that starts system from HDD.

atom.gif 30.4kB (2002-10-11 14:33)

Schematics v2.1 by Edwin Blink.

Links to other pages

http://home.wanadoo.nl/edwin.blink/samcoupe/

Blinky's Sam Coupé page. You can find more about Atom there.

http://zxvgs.yarek.com

ZXVGS and CPM22QED are operating systems that can use Atom in Sam.

See also

Sam Coupé

The Sam Coupé computer by MGT.

QDISK

QDISK is a IDEDOS partition software for many platforms. Also can convert B-DOS RECORDs.

DSKHNDLR

Low level floppy and hard disk drivers for Z80.