der Mouse (mouse@Collatz.McRCIM.McGill.EDU) wrote:
: What I know works: the iomega-provided cable, to a DB25 F-F
: gender-bender designed for RS232 (this is why I ask why serial 25-wire
: cables won't do), to a Macintosh-to-Centronics scsi cable, to a piece
: of ribbon cable with two Centronics sockets on it (presumably taken
: from a dead drive at some point in the past), to a Centronics-to-DB50
: cable.  We've found a shop that is willing to do custom cables, and are
: having them wire up an appropriate cable, based on handing them the
: above mess and saying "here's your reference for the wiring".

*shiver*

you should double check the result with a meter, before paying. Well, at
least before even trying if this works.

(I've had my experiences with equipment built to spec....

I once was trying to write a test version of a controling software for
some vacuum pump. The electronics "my" microprocessor card interfaced to
was supposed to give an interupt when the meter had read out the pressure.

I double checked my code. It didn't get results.

I triple checked. It didn't get results.

I stood on my head to read the listing of my code, to enhance blood
circulation in the brain. ( No, not really ;-) Anyway, it didn't work.

Finally I told that my supervisor, a PhD student who was supposed to set
all that system up, and had students like me to program little pieces.

He scratched his hair, and said "well, lets look at it". He took an
oscilloscope, looked at the interrupt line, and found it would get
pulses from 0.2 V to 0, instead of 3 V to 0.6 V or so...

It turned out that that piece of electronics, designed to be (in the
interupt output stage)

---------+----- 5V
         |
        +-+
        |1|
        |k|
        |O|
        |h|
        |m|
        | |
        +-+
         |
         +-------o int line
	/
      |/
------|
      |\	
        \
     ----+---Gnd


was instead wired:

         
           +------+
         +-|1kOhm |------o int line
	/  +------+
      |/
------|
      |\	
        \
     ----+---Gnd


Well, Ignatios telling war stories from his youth... I'm getting old. 

Regards,
	Ignatios Souvatzis