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8087 co-processors.

PostPosted: Sat Apr 16, 2016 2:46 pm
by RdM
I have two of these, one labelled C8087-2 and the other C8087-3

No pics at present. Could take some if wanted.

Pins have been stuck in (one on each side!) a small piece of ant-static foam for years.

Pretty sure they came from working XT machines (the old Corona desktops). :(

Slight bubbling of the gold square, and some tarnish or corrosion showing on the leg mounts, although gold-plated - perhaps it was porous enough to allow some atmospheric interaction?

Thought I'd offer here to gauge interest, before perhaps putting them on TM.


Re: 8087 co-processors.

PostPosted: Sat Apr 16, 2016 3:37 pm
I'm interested :)

Re: 8087 co-processors.

PostPosted: Sat Apr 16, 2016 3:45 pm
by SpidersWeb
I'm interested as well, have quite a few XT machines here that could use a bit of a boost in SimCity and Lotus 123 :)

Re: 8087 co-processors.

PostPosted: Sat Apr 16, 2016 5:28 pm
by RdM
OK, here they are...



I've made no attempt to clean them up - probably they would easily enough though.
C8087-3 looks worse, but the actual pins look OK. Hopefully it's just on the surface.
(I see there's a slightly bent one on C8087-2.)

Hmm, perhaps I should have listed them on TM after all! :shock:

However, I can't guarantee that they're working, but as I say I think there's a fair chance they will.

OK, how do we do this? PM me your details, for a start...

I could send as a letter, probably max thickness, to allow for padding,
or say in the smallest pre-paid padded bag, to which tracking could be added. ... ange-works

While I'm happy to see them go to good homes, any rounding-up of postage &or donation toward packing and a trip to the PO would be appreciated... :D

One problem might be finding another piece of foam;- they're back to back at the moment!

Re: 8087 co-processors.

PostPosted: Wed Apr 20, 2016 6:48 pm
by RdM

Cleaned up a bit, isopropanol & and an old genuine bristle French toothbrush (rare now) employed to help clean the upper edges...

It seems it was just colourful grime ...

And fine cotton cloth, a bit of a wipe-down.

Not perfect, nowhere near it, but perhaps an improvement

On foil, under lights.





Since then, I've thought;- do I have another XT PC left; that I could test these in?

- yes, a Zenith Supersport ZFL-184-01, an XT laptop that served well earlier... the printed book manual I have shows me that there is an option 8087 slot, easily accessed; I've checked and seen that it's empty.


Question is, if it goes again after all these years, which it might;- I had had fun even up to MSDOS6.2 with it, as I recall;- and even Win95 dos;-

(Update it does go, still!)

How can I check that an installed 8087 co=processor is installed, under DOS? Can it be shown existing and working, I ask myself, and search.

Apparently so, with MSD.EXE Version 2.11 (Microsoft Diagnostics Utility). So I've downloaded that. But will need to organise another DOS PC to copy.
Or make up a Laplink cable again, or find my old one... it's been a while since I was back in this realm!

And, I've learned more about 8087s, and that the Zenith specified an 8087-2 -

So I'm going to hold off on the offer until I can prove that they're recognised. Which means also building/configuring a DOS PC again.

The most likely (and slowest) candidate I have now (apart from the said Zenith & the possible Corona luggables) is a Compaq DX2-66 (or DX4-100).

Thanks for the PM, ZL2AOX - the Amiga keyboard is certainly yours, and for the note of interest, Spiderweb.

Bear with me while I venture back & check them out...

For some reason Happiness Stan , Ogden's Nut Gone Flake comes to mind...

Cheers! ~ Ross.

Re: 8087 co-processors.

PostPosted: Wed Apr 20, 2016 11:20 pm
by SpidersWeb
Generally on a PC there will be a configuration chip to enable the 8087.
If the switch is set, and the co-processor is faulty or missing, it should generate an error.

Re: 8087 co-processors.

PostPosted: Wed Jun 22, 2016 12:57 pm
What is happening about these?