View Full Version : DEC IEEE 488, IEC controller M8634 value ?

March 26th, 2009, 01:45 AM
Hi all,

I recently got a DEC M8634 card.This is GPIB right ?

I have no use for it, so do you know what it's worth ?

I can get a picture uploaded here later.

Terry Yager
March 26th, 2009, 01:59 AM
Hmmn, tough call. It's worth nothing to most of us, but 'about a hundred dollars'

/rainman mode

to someone who needs it. (There's still a (small) market for it).


March 26th, 2009, 02:03 AM
I recently got a DEC M8634 card.This is GPIB right ?

I have no use for it, so do you know what it's worth ?
Probably not very much. A lot of Qbus cards like this end up on eBay starting around $10 and only get one or two bids, if any.

Lou - N2MIY
March 26th, 2009, 03:08 AM
The M8634 is the IEQ11. It looks to me to be the most sophisticated IEEE-488 card made. It is quad height and has two IEEE-488 bus connections (two separate TMS9914 controllers). It can also do DMA.

I have one of these also. One does not see them much. The problem is that I have never found enough existing software to actually use mine. It came in a machine running RSX that was used at a university. I got the whole machine, but the hard disk is irreparably gone.

For a long time, I have been looking for the RT-11 utility package for the IEQ11. It's called IEX-RT and was written by some dec software group in Germany. I have never found it. I have the card manual, but not quite the enthusiasm to write the macro-11 code to make a driver (that I can link in fortran or basic).

Dec also had the dual height IBV11 for IEEE-488, but it was a non-dma card and it relied much more on software running on the 11 to talk properly on the 488 bus. At least there are fortran-linkable routines already available for it from the decus archive.

Cosam is quite right that many qbus cards go for $10 on ebay, and this card is even less useful to the average guy than other $10 cards. One can build a whole machine one card at a time with $10 cards. I think this card is no exception unless someone still having an industrial / research system needs one. Maybe it's worth more if you have the cables that go from the 40 pin berg connectors to the usual 488 stacking connectors.

If there is anyone else out there with IEEE-488 hardware on their Q-bus machines, I would be interested to hear from them. I have a National Instruments GPIB11-V2 in one of my 11/23s. I have the NI drivers and have patched Basic-11 V2 for a programming environment. I have HP daqs attached. Like IEX-RT, I'm also looking for the NI drivers for the GPIB11-V1 card (68488 based instead of 9914 based).


March 26th, 2009, 05:25 AM
Thanks guys. I will keep the card as a "cool-to-have" item, but if any of you need it, gimme a PM.