The long wait is over!

I have a working sound card using a CPLD instead of the P82C611. It works in my PS/2 Model 50Z and it seems partially functional in the Model 95 I borrowed (the card ID gets read successfully by the BIOS but the machine can't boot due to issues with the floppy controller.)

Twitter announcement here: https://twitter.com/TubeTimeUS/status/1215071399829622784

Git repo here: https://github.com/schlae/plaid-bib-cpld

If you build the card and get it working in your MCA bus machine, please let me know so I can add it to the compatibility list.

Enjoy!

Although I have no PS/2 systems all this work you've done is simply amazing, kudos TubeTimeUS!!!!!
In essence it makes finding a nice PS/2 system a viable option if someone wants to actually use the system and not just display it on a shelf.

The Plaid Bib (CPLD edition) has been tested and works fine on a PS/2 Model 85 (486SX). This is a great positive sign; there's a good chance it'll also work on other fast MCA machines!

Thats very good news and very good work. 👍

I have a Model 80 PS/2 and I'am interested to get one of the Plaid Bib cards. Though my soldering skills are rather basic.

Is someone going to produce some cards (ready to plug)?
I would compensate the efforts.

elianda wrote on 2020-01-27, 20:10:

[...]

if there are kits or something send me parts - I'll solder them for you no worries 😀

Here is some update from me. Eric sent me a Plaid Bib CPLD Edition and (after 11 days being stuck at customs) it finally arrived today.
It works in my Model 80. The only very minor issue I noticed is that sometimes after exiting Windows for Workgroups 3.11 the card gives loud noise until reinitialized. However this might be some software issue and not the cards fault at all.

Here are some pics:

It is the small card without shield.

That's excellent news! Today I had success using the card with the PS/2 Model 95 (Type-2 CPU complex with a 486DX2-50).

That card looks really nice ~

Tiido wrote on 2020-02-13, 03:17:

That card looks really nice ~

I also wanted to post that but forgot, it really looks very nice and the solder job is great

Another update

We identified an issue in combination with memory expansion cards that use the MCA feature Matched Memory Cycle. Most memory cards use this feature for optimal transfer speed.
The issue appears when data is read from the OPL2 and randomly locks up communication with the card. To revive operation a power cycle is required.

Usually one would consider that the OPL2 is not used much with reading from it because playing music is mostly writing data.
Though the OPL2 is slow and requires delay after writing the address byte and after writing the data byte. The standard way for an ISA card that also the example music player uses on the Adlib disk is
6 dummy port reads after writing the address and 35 dummy port reads after writing data.
Basically every game/application that has Adlib support uses that approach as well.

My testing shows that the communication often get borked when starting a game and the code tries to detect an OPL2. When the a game runs it seems to work without failing intermittently.
Without extensive statistics I tried on Commander Keen 4 and on the 6th start the card went silent.
Some games seem to hit the issue always on startup like Legend of Kyrandia, which stayed always silent.

The problem is gone as soon as the memory expansion card is removed.

TubeTimeUS knows about the issue and I sent him also the test programs I wrote.
Maybe someone lives close and can borrow him a Model 80 for testing?

Does it work in 55SX ? 😀

matze79 wrote on 2020-03-28, 21:07:

Does it work in 55SX ? 😀

It should but nobody has tested it yet.

Ok,
i will try soon.. but have some problems currently to order parts.

it would also be nice to get a Storage Solution for MCA,
maybe a IDE MCA Card 😀

Oh IDE MCA card, yes!

I had one with model 70 once. Works great. I think Arco 1070 but mine had a larger IC than this, maybe acard?

Cheers,

Hi there, awesome work!
I´m a proud owner of a Ibm Model 70 386 and i am so hyped about the fact that there is finally someone who cares about the old IBM hardware.
Unfortunately, I do have an issue with my Computer. My SCSI Controller doesn´t seem to work properly, so i do have to stick with my old 20MB (still working) ESDI hard drive.
IDE Controllers are just impossible to find 🙁

The Second problem. I don´t have a soundcard. I think my soldering skills are decent (i have already fixed the old floppy drive with some new smd capacitors)
but i do not have any experience in IC programming nor do i know how do i easily get all the components to tackle this project.
Hopefully someone here could give me an advice, because i would love to see this baby running again with many many games and stunning Adlib Sound.

Here are some pictures:

Datasheet:
Intel A80386DX-20 Mhz
20MB ESDI HDD (with Windows 3.1)
4Mb Ram
IBM computer Basic C1.10

MCA Cards (All cards are functioning):
- IBM SCSI-2 F/W Streaming-RAID /A 'Cheetah' (common ADF File dosn´t seem to work)
- XGA Display Adapter/A (FRU P/N 96F7658 | OPT P/N 75X5887)
- Kingston KTM 16000/386 16MB (10MB installed)
- IBM 90x9482 8570/8520 2-6MB Ram Expansion Card (4MB installed)

Ok quick update:

I followed the instructions on the "The Plaid Bib CPLD" github site and ordered the PCB by using the Fab files on PCBWay.
Then I used the "Bill of Materials List" to get the parts from the mouser electronics homepage and some missing components from ebay.
Adittionally i ordered TubeTimes PS2FloppyAdapter to give it a try with my unused Gotek drive.

I guess this was right so far?
If so, i am just a little worried about programming the CPLD.

I do have a raspberry pi but i´m not sure if i am capable enough to wire the thing correctly.
Hopefully someone could help me out when the parts have arrived.

Anyone selling assembled units of this card? I just picked up what I thought from the pictures was a model 30, but to my disappointment is a Model 55SX and of course it has no sound card.

TexElec released their assembled card for sale couple of days ago. When I saw that price, it was one of those "shut up and take my money" moments 😁

https://texelec.com/product/resound-2-opl3-mc … nnel-computers/

Interesting, however it is somewhat unclear to me from the description if it works in a faster MCA machine like a Model 80 and if the lockup issue in combination with memory expansion cards is resolved.
The description does not mention any of these points that came up here in the thread.

Is anyone aware of a MCA Soundblaster (Pro) clone project?