UM82C55A Overview
The UM82C55A is a high performance CMOS version of the industry standard 8255A and is manufactured using a selfaligned silicon gate CMOS process. It is a general purpose programmable I/O device which may be used with many different microprocessors. There are 24 I/O pins which may be individually programmed in 2 groups of 12 and used in 3 major modes of operation.
UM82C55A Key Features
- Pin patible with NMOS 8255A
- 24 programmable I/O pins
- Fully TTL patible
- Bus-hold circuitry on all I/O ports eliminates pull-up
- High speed, no "wait state" operation with 8M Hz
- Direct bit set/reset capabi lity
- Enhanced control word read capabi lity
- Single 5V power supply
- 2.5mA drive capabi lity on all I/O port outputs
- Low standby power -ICCSB = 10llA