WD4020 Overview
System oscillalor output System oscillalor inpul 8 bidirectional ROM address and dala ports Syslem reset Input 8 bidirectional I/O ports with TRI-STATE® 4 general purpose Inputs Power supply Ground Serial input (or counter input) Serial output (or general purpose output) Logic-controlled clock (or general purpose output) 4 bidirectional I/O ports Instruction skip output Address out/data In flag 2 ROM address outputs...