Johnny's home-built CPU corner (and other stuff, maybe)


8080 CPU, built entirely by DTL-technology

Microcode Sequencer


Question : How do one build a synchronous 5-bit counter not using a JK-FF  ??

Answer   : By using D-FF and a streamlined 7480 full adder !


This counter ticks away at 2 MHz without problem. Precisely what I want/need.


The schematic is here..:

Only one D-FF and adder is shown, they are all alike.


This one is for the D-FF #4.

Homebuilt CPUs WebRing

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