Serial Display

A serial display can easily be made by adding serial to parallel shift resisters. A serial-in parallel-out shift register (74HC164, 74HC595, CD4094.....) can be added to a 7-segment display as per the tutorial provided in this link. The adding of the shift register minimizes the number of pins used by the 7-segment display. This topic shows how to make a 4-digit digital counter with multiplexing and 74HC164 shift register using PIC16F84A and CCS PIC C compiler.