I've never heard it called "PCISA"...

PISA is the search term you want.

ajacocks wrote on 2024-02-28, 17:32:

The recent topic on ISA Riser problems got me thinking about a nice low-profile 486 that I have that came with a PCISA riser car […]
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The recent topic on ISA Riser problems got me thinking about a nice low-profile 486 that I have that came with a PCISA riser card that I did not get with the system.

For anyone not familiar, PCISA is a pseudo-standard that became somewhat common for industrial backplanes, combining PCI and ISA into a connector that looks very similar to EISA, and can be seen in this other thread:
PCISA158V Socket 7 SBC long looping beeps, any documentation available?

I'm looking for a PCISA riser like this:
https://web.archive.org/web/20240228165318/ht … tm/325704265110

It has 2 ISA and 2 PCI slots, one shared. What makes it unusual is that the slots are facing to the right, when facing the front of the machine. Most risers are facing left.

Does anyone have a suggestion for an alternate riser that I could use, since this seems to be uncommon?

Thanks!
- Alex

Interesting.
Care to share some photos of the pcbs in that low-profile 486 you have ?
Is it of the Tulip computer brand ?

edit: Looking for the other number present on the riser card gives a listing on ricardo that hasn't been sold there. you could try contacting the seller there and ask if he still has that part if that is the one you are looking for.

Recently saw one with that type of edge connector in a Packard Bell tower video on youtube. Not sure if the slots are on the right side for you for those though.

I am wondering if there's a semi-standard for the "almost an ISA 16bit slot but there's 4 pins in the middle where the notch would be" type.

Edit: ah still had vid in history
https://www.youtube.com/watch?v=YXruKS5xT7A
time of about 7:30 to see the tower version about 22:00 to see the desktop version... though unless somebody's camera is flipped the slots seem to be on the wrong side for you. Don't know if PB did any with a different orientation.

BitWrangler wrote on 2024-02-28, 18:03:

Recently saw one with that type of edge connector in a Packard Bell tower video on youtube. Not sure if the slots are on the right side for you for those though.

I am wondering if there's a semi-standard for the "almost an ISA 16bit slot but there's 4 pins in the middle where the notch would be" type.

It's called PISA and it uses an EISA edge connector.

I've not seen it called "PISA." The boards that use it that I have seen (they are still for sale, new, for industrial use, call it "PCISA":
https://www.icpamerica.com/pcisa-945gse-n270- … -half-size-sbc/

Yep, the machine I have is a Tulip, rebadged as Unisys. This is the motherboard:
https://theretroweb.com/motherboards/s/tulip-computers-tc40

The machine, in unisys form is the CWP 4663, seen here:
Unisys CWP4663 - 486 DX2 system - jumper setting
and here:
https://twitter.com/FozzTexx/status/128684630 … 9112960/photo/1

There are lots of PCISA/PISA risers on eBay, but they are almost all facing left.

Thanks!
- Alex

ajacocks wrote on 2024-03-01, 00:19:

I've not seen it called "PISA." The boards that use it that I have seen (they are still for sale, new, for industrial use, call […]
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I've not seen it called "PISA." The boards that use it that I have seen (they are still for sale, new, for industrial use, call it "PCISA":
https://www.icpamerica.com/pcisa-945gse-n270- … -half-size-sbc/

Yep, the machine I have is a Tulip, rebadged as Unisys. This is the motherboard:
https://theretroweb.com/motherboards/s/tulip-computers-tc40

The machine, in unisys form is the CWP 4663, seen here:
Unisys CWP4663 - 486 DX2 system - jumper setting
and here:
https://twitter.com/FozzTexx/status/128684630 … 9112960/photo/1

There are lots of PCISA/PISA risers on eBay, but they are almost all facing left.

Thanks!
- Alex

I've definitely worked on some Pentium 1 era Gateways that had the mirrored risers. Check that out.

Here's the official PISA spec from 96 https://www.kontron.com/download/download?fil … f&product=87006

You are indeed correct! I had never seen that.

Thanks.
- Alex

I found (thanks @kingcake) a riser that will do, until I find the right one:
https://web.archive.org/web/20240305153515/ht … tm/193646674657

I may just have to break down and do my own PCB design. ISA and PCI aren't all that hard to lay out, and I can copy an existing riser. I just wanted to be lazy and buy one!

- Alex