W65C21S
The W65C21S is a very
flexible Peripheral Interface Adapter (PIA) for use with WDCs 65xx and other
8-bit microprocessor families.
Product
Features:
Two 8-bit bidirectional I/O ports with per bit data direction
control.
Automatic Handshake control of data transfers
(4) Programmable interrupt control lines (two for each
port)
Register and Chip Selects specified for multiplexed operation