Howdy all,

Decided to convert my manual SW-coded PWM LED dimmer to
use the PWM feature built into the 16F872 instead, but...

All 8 pins of Port C are already in use -- one port to
reduce flicker at low-ish frequencies.

Port B has the switches, and uses the internal pullups.
Also, RB6:7 are open for ICSP later.  Port A has one
A/D in use and drives the individual segment commons.

As is become a trait with me, external components are
frowned upon, primarily due to space considerations,
when a SW solution exists.

I haved used the internal PWM module yet, but from the
datasheet, I gather that to implement a dimmer, I will
need to setup the PWM, have it drive RC2 accordingly,
and I could monitor that pin to turn the display on/off
accordingly.  Alternatively, I could use another
transistor driver, the collector of which would supply
the emitters of the 4 existing transistor drivers with
a PWM-modulated supply-rail signal.

Few Q's...
Is this even the right way to do it?  Or is there a
better way?

Is there any way to do this w/o needing RC2? -- I'm
hoping for some internal way to read the PWM output,
since I don't need a physical I/O pin set.

However, since the segments are on port C already,
perhaps I could find a way to monitor the change on
the CCP pin and adjust all the other segments
accordingly.


Cheers,
-Neil.

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