Non-PCM games

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Early games that don't use combined ADPCM-A and ADPCM-B V ROMs (no PCM chip):

PCMization

It may be desirable to "PCM-ize" these games for converts or emulation.

This is not a very simple and straighforward task. As countrary to PCM games which are forced to use different addresses for their ADPCM-A and B samples, non-PCM games have all the liberty to use overlapping ones since two distinct ROMs are used.

The V ROMs must be concatenated, and the sample address tables in the M1 ROM must be edited to reflect the new offsets. Because sound drivers are all slightly different, some code reverse-engineering is in order.

De-PCMization on the other hand would be easy, but rather pointless.