On Tue, 21 May 2002, Jinx wrote:

>>    Bouncing at bottom contact will produce 0 - 0.5 Vdd noise.
>>    Bouncing at top contact will produce 0.5 - 1 Vdd noise.
>
>Exsqueeze me ?
>
>Noise coming from the switch will be 0-5V regardless. It
>must be as a consequence of the contacts touching or
>otherwise the switch wouldn't be a switch, unless it came
>from the Pisspoor Switch Co catalogue

The bounces are so fast that the line capacitance does not allow them to
raise/drop fully fefore the next one comes. This is how simple
capacitor-only debouncing works. There are several hardware debouncing
schemes that do not like this kind of noise, and fail.

Peter

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