Counter and bell player for boxing ring.
This is a PIC16F84 based boxing round counter and boxing bell controller. It displayed the current round in two 7-segment displays scrapped from an old microwave oven, and there was a switch used to select between amateur and professional that set the round time to 120 and 180 seconds respectively. The code was made in PIC assembler. Schematics are lost, but I'm pretty sure I used external buffer ICs to control the displays.