Changes
/* PlayCity: Partially compatible */
Sound capabilities are also quite different. The Play2CPC is equipped with an OPN3 (ymf288) soundchip. It offers 6 FM chans and 3 PSG chans.
The PlayCity is equipped with 2 PSG chips soundchips offering a total of 6 PSG chans, but zero FM chans.
So the few PlayCity programs using 9ch AY will be not replayed by the Play2CPC.
