UM6520

(l)UMC UM6520 / UM6520A Peripherald",',,""''"'"''''''''.''''' Interface Adapte,(PIA) Features Direct replacement for Motorola MC6820 Single +5V power supply Two 8-bit bi-directional I/O ports with individual data direction control CMOS-compatible peripheral port A lines Automatic "handshake.' control of data transfers Programmable interrupt capability Automatic initialization on power up 1 and 2 MHz versions General Description The UM6520/A peripheral Interface Adapter (PIA) is designed to provide a broad range of peripheral control to microcomputer systems. Control of peripheral devices is accomplished through two 8-bit bi-directional I/O ports. Each I/O line may be programmed to be either an input or an output. In addition, four peripheral control lines are provided to perform "handshaking" during data transfers. Pin Configuration Block Diagram VSS PAO PA1 PA2 PA3 PA4 PA5 PA6 PA7 PBO PB1 PB2 PB3 PB4 PB5 PB6 PB7 CB1 CB2 VCC CA1 CA2 IROA IROB RS...