What brought this on was the write up at http://circuit-bent.net/pss-270-tutorial.html detailing the trace cutting bend for PSS-270. After researching the chip for a few minutes I learned that it is a Simple FM sound generator that uses an 8-Bit data bus to control all of the registers. Unfortulatelly I couldn’t find a supplier for the chip, but I would be willing to bet that any basic Yamaha keyboard has one. However one thing that is for sure this chip is in the Sega Master System along with a relative of sn76477. Cutting the datalines would get some interesting results for sure, but pumping data into the chip should be quite fun as well. It just so happens that I have a Master System laying around and I am not afraid to gut it. Maybe sometime next week.
Great YM2413 info.