Possibility of making clone MCA sound cards.

[gslick]

Anyone have a copy of The IBM PS/2 from the Inside Out by Tom Shanley, ISBN-13: 978-0201570564?

I can't remember if I had a copy of that and how detailed it might have been about the MCA bus design.

[Chuck(G)]

Haven't we already been through this MCA discussion recently via a marathon thread spanning 8 years?

[luckybob]

I have a mca soundblaster pro and a nice phone camera. So if you need images, I can provide.

[TrekkiesUnite118]

Then looks are very deceiving. MCA is light-years from PCI. It's really a close cousin to ISA. Forgetting the DMA interface (which would not apply to Adlib anyway), MCA is ISA with a few 8-bit registers. One returns a static board ID and the others are optional to soft-configure IRQs and DMA channels. A small 5V PLD like a ATF150x could easily do the job for a simple PIO board. Other cards used SPLDs or even discrete logic. The Roland intelligent MIDI board (MPU-IMC) is a good example of discrete logic, fixed I/O addresses and interrupts, and all the ADF file does is make a fixed reservation in the setup disk utility.

MCA is pretty well documented in the PS/2 technical references.

Oh I didn't mean they were similar in standards, pinouts, architecture, etc. I know they're radically different. I simply meant in terms of physical size, pincount, and shape it's similar enough that if push came to shove you could probably rig a blank PCI prototype board to work in the slot, as well as use a PCI template in whatever PCB layout software you used to design a card.

I have a mca soundblaster pro and a nice phone camera. So if you need images, I can provide.

Go for it, even if this doesn't get off the ground better pictures of some of these obscure cards would probably be appreciated for various things.

[glitch]

Prototype boards aren't that big of a deal, they're quick and easy to lay out.

[njroadfan]

Then looks are very deceiving. MCA is light-years from PCI. It's really a close cousin to ISA. Forgetting the DMA interface (which would not apply to Adlib anyway), MCA is ISA with a few 8-bit registers.

DMA is what makes a SoundBlaster..... a SoundBlaster. Most of that is handled by the MCA bridge chips like the CHIPS one mentioned earlier. Intel made one too, but don't know the part number off hand. Creative was pretty lazy when they made their cards too, no programmable option select, they were still configured with jumpers! Those cards had problems with faster machines and DMA too.

Regarding what to clone, duplicating something like the SoundPiper or ChipChat would be easier since they use "all-in-one" ESS chips. For the purists, the Soundpiper used a real OPL3 alongside the ESS688.

[eeguru]

I did say "which would not apply to Adlib anyway" since that was the OP's original recreation interest.

There are two ways of doing DMA in MCA, card self bus-mastering and the traditional 8237A initiated transfers. I don't know of many cards that did the former. However the later is still a lot like ISA. The first 8 arbitration IDs map to the same 0-7 DMA channels on a similar cascaded 8237A setup. It's not quite PC compatible though. It's hit or miss whether software written for PC/AT back then will work on a PS/2 in DMA mode.

As far as PCI physical similarities, they have the same connector pitch and rough size (card height and pads). But PCI has 36 (with the voltage key) and 49 pin fingers (without) while 16-bit MCA has 45 pins per edge. MCA also specs power pins should be recessed in order to make connection last (as all good specs should dictate). I have a tested Eagle library footprint if it will save anyone some time.

I have a lot of MCA related projects spinning in my head but no time to commit.

[Unknown_K]

Even creative MCA Soundblasters were not that great for gaming on a PS/2.

[Trixter]

Even creative MCA Soundblasters were not that great for gaming on a PS/2.

My experience many moons ago with the actual MCA SoundBlaster is that it worked with games about half the time. OPL2 usually worked, but digital sound was 50/50.

[Goodtofufriday]

I have a mca soundblaster pro and a nice phone camera. So if you need images, I can provide.

That's be pretty great if you could! No high res photos anywhere.