9 Dec
2009
9 Dec
'09
6:41 p.m.
On 8 Dec 2009 at 19:19, Tony Duell wrote:
I thought you had enough outputs to have an ATN line, so you could do
addressing. I think you can have multiple devices hooked up to a PC
printer port pretending to be GPIB. But I don;t thinkl you can respond to
paralell polls on the PC. I seem to remembr you are short of I/O lines,
you can't have all of the bus control lines. Missing out EOI and SRQ is
not a problem if you just wnat to talk to an HPIB plotter, it is a big
problem if you are tryin to emulate an HPIB disk drive.
I don't think a PC printer port can do that,
can it? A Victor
9000/Sirius printer port on the other hand...
Depends on the device. If you have a bidirectional printer port (or
hack a unidirectional one to be so) you can communicate with a
variety of GPIB devices, so long as you're not sharing the bus with
more than one device. Many years ago, I wrote a DOS TSR to drive a HP
plotter with HPIB
interface from a PC XT with a bidirectional-hacked port. It
redirected the BIOS printer service interrupt, so you installed
whatever software you had (in my case, SuperCalc) and told it you had
a parallel-interface version.
I think I used a modified version of the software to later talk to a
HP voltmeter.
It's probably still buried somewhere in the SIMTEL library.
If not, I have one of your GPIB-on-a-printer port programs here. It's the
old one that uses an original PC printer port card with the well-knwon
cut-and-jumper mod (why this isn't docuemtned in the IBM manuals is
beyond me, the board is clearly laid out for it).
-tony