> I've set up Timer0 to interrupt on overflow every 1ms to create a
> system 'pulse' for resetting the external system supervisor, updating
> any non-zero counters, etc.  No other interrupts are used.  My
> button-checking routine is called every 73ms when its dedicated
> counter times out.  The problem appeared as an endless series
> of random false button presses

You say "random" but are the noise spacings multiples of 1ms or
73ms ? The actual T0 IRQ looks to be 1,000,000 / 4 / 256 = 976us.
Is that clashing with the 73ms routine somehow ? Are you context
saving / restoring in the ISR ?

===================================================

Love the Subject btw, very clever. You sure you haven't got a bunch
of sexually dysfunctional chips who are just noisy boys?

http://www.inkblotsmag.com/critiques/literature/portnoy.html

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