[Non-MSX] Strange board with Y8950 chip

Hero (651)

05-07-2019, 15:08

More than 20 years ago my friend gave me a board saying "it has a MSX AUDIO chip on it". I didn't hear its purpose. Can anyone guess what is this board for?
https://www.msx.pics/album/jhbV
It looks like an IBM PC soundboard but it might not be. Searching by the model names written on it returns no result, though what I know are;
- "FMV" is the name for well known PC series from Fujitsu.
- A silver capacitor's leg seem to be disconnected, either because of external impact or intentionally done so.
- The manufacturer's name hidden below the capacitor is "Takashima & Co., Ltd."

بواسطة Wild_Penguin

Hero (644)

05-07-2019, 16:24

Very Interesting!

No replies yet? Is everyone at a bar because it's friday and summer?

Anyways, it also has the OPL2 chip (YM3812) in it. It most certainly is a IBM PC soundcard, since the form factor matches. Too bad there is no other information.

You could check it's pinout (from the card edge connector) and compare where everything is connected to the ISA bus pinout, to make sure it is a PC ISA card (are there any other computers with same form factor, like Amiga? It would be very weird to have MSX-Audio on a Commodore Amiga, though! ).

"Game" would probably refer to Game port. There is nothing hinting the card having any video capabilites. There is one larger chip (U26) which is unreadable in the picture, is it unlabeled? My guess would be it is a ROM chip.

Since it has the Y8950 chip, and is in ISA form factor, perhaps it was meant for the PC/MSX hybrid machine?

Hang on to it, might be valuable! Possibly almost unique

بواسطة Wild_Penguin

Hero (644)

05-07-2019, 16:37

I compared the pinout to PC/XT-bus. https://en.wikipedia.org/wiki/Industry_Standard_Architecture

It most certainly looks like a PC 8-bit ISA card. Maybe it is some kind of Sound Blaster clone card? Can the Y8950 (with some logic, which there is a lot on the card) be used to emulate for the digital side of a SB 1.0? There are even empty sockets which could be meant for Game Blaster compatibility! However, after a quick glance none of the DRQ lines are attached. I believe a SB1.0 needs one. Maybe it is an Adlib clone then ... with a Y8950???

Ah well, just some speculation B-)

بواسطة Takamichi

Hero (651)

05-07-2019, 17:01

Thank you for your reaction. Game port... I forgot such thing like the joystick port attached to soundcard existed. Corrected my page accordingly.
The seemingly blank chip above Y3812 has black texts on it. They say;
NEC JAPAN
D8251AFC
9117M5012

Another black chip right to Y8950 says;
PALCE16V8H-25PC/4
11 3A7KV
FMV-01

So my question is, can I really test it on my PC and it won't blow up PC to pieces? Especially scared with the one-legged capacitor. Maybe I should ask a PC expert prior.

بواسطة meits

Scribe (6576)

05-07-2019, 19:08

I got pointed at the date code on the Y8950. It suggests 1990. That's later in any MSX equipment.

بواسطة RetroTechie

Paragon (1563)

05-07-2019, 19:51

Takamichi wrote:

NEC JAPAN
D8251AFC

This is a classic Universal Synchronous / Asynchronous Receiver & Transmitter. That is: a chip for sending & receiving serial data. No doubt used for the MIDI part.

The PALCE16V8H is some programmable logic chip. Mostly used for address decoding or similar jobs.

Seems like an 8-bit ISA card indeed. So soundcard for a PC XT. Not all those were SoundBlaster compatibles you know. There was quite a variety among chips on early PC soundcards. Come to think of it, are most SB cards (& clones, and successors) not more the domain of later machines like 386/486 era?

Quote:

So my question is, can I really test it on my PC and it won't blow up PC to pieces?

To be safe, you could check power supply connections / voltages. What's used on the card (IC's!), what pins on the edge connector it's pulled from, and what a PC XT has on same pins in the slot. As long as power connections match, odds are pretty slim that a card gets damaged.

Quote:

Especially scared with the one-legged capacitor.

That's out-of-circuit then? Harmless. Might as well remove it. Or if there's a solder spot for the other pin, you could also replace it.

بواسطة Takamichi

Hero (651)

06-07-2019, 06:37

Meits wrote:

I got pointed at the date code on the Y8950. It suggests 1990. That's later in any MSX equipment.

45th week of 1990 is almost same as the A1ST release date. Maybe someone was planning to release something with Y8950 at the same time? To think of that there is no source indicating discontinuation and Y8950 is sold at low price in Alibaba so it might be still ongoing.

بواسطة Takamichi

Hero (651)

06-07-2019, 06:44

I was stupid enough to think this board would fit PCI. The terminal width is same but PCI has much more pins. Ebay does seem to sell many PC XT but I don't think buying that just to test this board is worth, it'd be better only to keep it as a relic... :(

بواسطة Pentarou

Hero (563)

06-07-2019, 10:20

The best place to ask for info, for this kind of hardware, are Vogons.org forums.

Did any old JPN PC have ISA?
I find very strange that this board was manufactured by a Japanese company for western PCs... It has the UL mark but there's no FCC ID, so it can't be legally sold in the US?
And it's also strange that it uses a mini-din for MIDI connection: All the SB and compatible boards used the GAME connector with an adapter.

To use this board you will have to figure out the jumper settings (for I/O & DMA addresses), and you will also need the proper drivers/software. Maybe you'll get SB/ADlib sound with generic SB drivers but I doubt the Y8950/MIDI parts will work.

بواسطة RetroTechie

Paragon (1563)

06-07-2019, 13:41

This card should plug into any ISA equipped PC motherboard. Which are rare these days, but not that difficult to find or expensive. So you don't need an old XT PC for that. For example I have a Pentium board with a bunch of CPU's to choose from, and a Pentium Pro board + matching CPU. Both around 1995 era, several ISA + PCI slots, ATX size & still working. Some limitations when mixing 8 & 16 bit ISA cards may apply though.

Pentarou wrote:

Maybe you'll get SB/ADlib sound with generic SB drivers but I doubt the Y8950/MIDI parts will work.

That seems likely. As for MIDI: the 8251 is (was) a veerry common chip. And AdLib/SB + MIDI combo's must have been done many times. Software doesn't care about connectors as long as things look the same from software p.o.v. So I'd give it a small but non-zero chance that MIDI part could work with the right drivers/software. But Y8950.. unless you find drivers specifically for this card, forget it.

Figuring out jumper / software settings could be a p.i.t.a. though.

بواسطة Takamichi

Hero (651)

06-07-2019, 17:29

Yes old Japanese PCs did have ISA bus, Yahoo auction ISA bus parts here. But old PCs with them are at 40000+ yen, new one at 160000+ yen (!) and a PCI to ISA converter costs 100000+ yen so I'll hesitate.
Possible implementation in something other than PC is a Yamaha musical instrument. They used so many FM chips, could have used much better Y8950 in high end models, my wild guess.