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A Nice Surprise

One of my personal "most wanted" games showed up a couple of days ago on my doorstep:
I realize it's not too exciting, but it has some interesting technical differences from the original. There is a small PCB attached in a fairly hacky fashion to the main board with lots of hand-soldered wires. Originally I figured this was some kind of protection scheme, but it turns out that they added a sample player. The original Crowns Golf played some samples through the AY-8910 chip, believe it or not. I don't know if MAME's 8910 emulation is quite good enough, but you can hear something sample-like.

The new board seems to offload the work to this small PCB. It writes out a starting sample address and just assumes that the hardware plays it. There are 3 TTL chips that have the part numbers scratched off on the board. One is 18 pins, one is 20 pins, and one is 8 pins. I'm suspecting the 18-pin chip might be an MSM5205. The next step is to try running the ROM data through an ADPCM decoder and see if something reasonable comes out. Some tracing of the PCB with a logic probe should also help piece together what's going on.

Suffice to say, this is kind of a nice break from looking at late 90's 3D games running at 5fps. I've also been changing several sound cores over to outputting at their natural rates, and letting the streams system do the sample rate conversion with full oversampling. This simplifies several of the sound cores, which is nice.