On Fri, 5 Nov 1999, Tracy Smith wrote:

> In the simplest case, 'co-routines' may be thought of
> multi-tasking with just two tasks: task_A & task_B.

  I commonly use this in PICs (and other micros) to operate the A/D.  I
set TMR0 to interrupt at 2x the sample rate, and in interrupt service
either sampling to the track-and-hold is done (state 1) or the conversion
is started (state 2).  I pick up the conversion result at the beginning of
the next sample service state.

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