7400 love

 
7400 love

The original circuit was entirely composed of 7449s (7-segment display decoders), 7490s (decade counters), and 7400 (NAND gates). The device functioned as a 6-digit BCD counter; cutting three traces broke it up into three 2-digit BCD counters (sharing the same reset line). The microcontroller refreshes all three banks once a second.

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