It also integrates a programmable sound generator (also known as APU, featuring twenty two memory-mapped I/O registers),[3] rudimentary DMA, and game controller polling.

[4] The Ricoh 2A03's sound hardware has 5 channels, separated into two APUs (Audio Processing Units).

The first APU contains two general purpose pulse channels with 4 duty cycles, and the second APU contains a triangle wave generator, an LFSR-based Noise generator, and a 1-bit Delta modulation-encoded PCM (DPCM) channel.

An interesting quirk of the DPCM channel is that the bit order is reversed compared to what is normally expected for 1-bit PCM.

However, most developers lacked the resources to properly adjust their games' music from NTSC to PAL, leading to many PAL games sounding slower, slightly lower-pitched, and in some cases, out-of-tune compared to their original NTSC releases.