RTL Design #9 · 2026-10-02 · Counters · Easy · about 10 min

A debouncer that adds up the bounces

debounce cleans up a bouncy switch. noisy is already synchronized to clk and is sampled at every rising edge.

• clean switches only when noisy has been sampled at the level clean doesn't have on 4 rising edges in a row. It switches at that 4th edge.
• A sample at clean's own level breaks the run: the next one starts again from 1.
• Reset sets clean to 0 and starts the count again.

A slow, clean press works. A bouncy one gets through too early. Fix debounce.sv.

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