Changes
/* PlayCity: Partially compatible */
Sound capabilities are also quite different. The Play2CPC is equipped with an obscure soundchip, the OPN3 (ymf288). It offers 3 SSG chans, 6 FM 4-op chans and 6 digidrum chans.
The PlayCity is instead equipped with 2 SSG soundchips offering a total of 6 SSG chans, but no FM and no digidrum chans.
So the few PlayCity programs using 9ch AY will be not replayed by the Play2CPC.
