This brings up the questions of how long an individual segment has to be
on, how quickly to refresh the display, and by how much you can
overpower each segment.  With 4 displays of 7 segments each, that is 4 *
7 = 28 LEDs to light in turn.

So, at best, each LED is on 1/28 of the time.  This is neglecting the
time between turning off one segment and turning on the next.  If you
have an LED rated at 10mA displayed 1/28 of the time, do you need 28
times the power?  Surely not.  The LED couldn't handle it and we can
rely on persistence of vision to some degree.

As far as looping through the segments, I would prefer to use a variable
with one bit set low and then rotate the byte once per segment instead
of using a jump table.  Either way would work, but I prefer seeing the
logic in the code.

If and when I get my code written for this project I plan to share it.
So, let's see who multiplexes segments first!  :)

Thanks,
-Pat

> There are quite a few advantages (theoretically) to segment
multiplexing:
>
> 1) You may not need high powered hardware since only one segment is on
at
> a time.
> 2) Depending on how you wire whole displays you may get brightness
> variation based on the number of segments that are lit. Since segment
> multiplexing only turns on one segment at a time, you should get equal
> brightness.
>
> BAJ

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