How to access the PSG via PPI
From CPCWiki - THE Amstrad CPC encyclopedia!
Programmable Sound Generator
The CPC uses the AY-3-8912 PSG. This chip features 3 square-waves channels, a noise generator and an enveloppe generator often used at high frequencies to make different sounds.
The same chip is used in the ZX Spectrum, the Atari ST, and some others.
Links
Video
Introduction to the AY-3-8912
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