On Sun, 6 Apr 2008, Christopher Head wrote:
> Assuming the 16F88 has a hardware PWM module (I don't know the part
> personally), why not just use 8 pins on a single port of each device?
> Have the F88 sit in a tight loop just doing MOVF PORT, W; MOVWF PWM; and
> dump the desired brightness to the port on the 18F252.

The only problem with using the builtin PWM of the PIC is I need to 
control three LED strings with each having a different level.  The 16F88 
and 18F252 and most other similar chips only have one, sometimes two PWM 
outputs which is sadly one or two less than I need.

But a tight loop toggling the bits on and off and reading 8 bits of the 
port would work.  I could use two bits to indicate which output I was 
selecting and the other 6 for 64 levels of brightness which will be fine 
for my purpose of displaying meaningless color patterns. :-)

--
Ian
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