> There's also an unavoidable 1-5ms between each time the console polls
> the pad.

I doubt it.
If the timing matters to you that much then interrupt driven response would
allow you to refine this timing vastly.
Even polling at 100 uS to 1 mS rate would not place an excessive burden with
a realistic cpu clock speed.
Overhead depends on how many pads are controlled by one processor but if
there is one cpu per pad-set (whatever you call it) you should be able to do
it sub mS with great ease. If you have many pad sets per cpu you may want to
be using a super cheap cpu per pad-set.


        RM

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