The 8255 PPI (Programmable Peripheral Interface) is a general purpose I/O chip.
The Internal PPI in CPC
- See 8255 (controls cassette, keyboard, psg, etc.)
Hardware Expansions with external PPI
- IDE8255 (harddisk interface)
- Panda Electronics Communications Interface Unit (8bit printer port plus general purpose 8bit I/O port)
- Maplins Amstrad Expansion System (Part 2) (6x8bit I/O port, using two PPI chips)
Datasheet
- Media:PPI M5L8255AP-5.pdf PPI Datasheet (Mitsubishi)