UM6522A Key Features
- Two 8-bit bidirectional I/O ports
- Two 16-bit programmable timer/counters
- Serial data port
- Single +5V power supply
- TTL patible expect Port A
- CMOS patible peripheral Port A lines
- Expanded "handshake" capability allows positive control of data transfers between processor and peripheral devices
- Latched output and input registers
- 1 MHz and 2 MHz operation