Does the PS/2 not have any 5.25" drive bays?
Weird. :) I'm not an IBMer
so I don't know these things, though I *think* one of the machines I used
to do CAD work on was a PS/2 of some flavour.
No, AFAIK the PS/2 cases had (special!) 3.5" bays only.
The size of the drive is mainly because of the PS
& case (the case is
*very* well RFI shielded)... the drive itself is a standard 1/2 height 360K
40TKDSDD 48TPI drive, with a standard 34-pin edge connector.
OK, that makes it useful. Would you happen to know what the pinout is of
the 37-pin connector, so that I can try to make use of the drive without
modification? Is it even possible to buy a matching female 37-pin
connector?
If it's the same as the XT external floppy connector (and I think it is!),
the 34 wires of the standard floppy connector are connected to the
'bottom' (higher numbered) pins on the 37 pin D plug. Pins 1,2,20 are no
connection, pin 3 is wire 2, pin 4 is wire 4, pin 5 is wire 6, etc. Pins
21-37 are all grounded.
It's a standard DC37 connector, available from any good electronics parts
place, I think. You can get solder, PCB mount or IDC versions.
[...]
Interesting. How are the drives interfaced to the
CoCos? I've got a
CoCo1, CoCo2, and CoCo3, but I've never found a disk drive for these
machines.
You need a disk interface cartridge. It fits into the ROMpack slot, and
it contains a ROM containing the disk extenstions to BASIC and the disk
controller (WD1773 in later models, WD1793? in earlier ones). The disk
drive plugs into a 34 pin connector on the end of the cartridge
Late version disk interfaces (FD500 and later) work in all CoCo's. Early
interfaces need a 12V line (I forget if it's +ve or -ve) that's only
available on the CoCo1. Of course there's nothing to stop you hacking it.
Heh. I couldn't even get mine apart, because of
the two six-pointed
screws on the bottom. The screws have a lump in the middle so I can't use
a flat-blade screwdriver as I did when I had a similar problem opening my
Mac 512K.
Tamperproof TORX screws. Drivers for them are available from good tool
shops in the UK - I have a reasonably complete set to deal with such
things...
Doug Spence
--
-tony
ard12(a)eng.cam.ac.uk
The gates in my computer are AND,OR and NOT, not Bill