G'day all, just getting back into starting to get some stuff
happening with PICs, and am after some advice/help as to whether I'm
understanding things correctly.
  I am trying to figure out how to play a 16kHz 8bit sound; I think
I've got the method for converting sound to hex file sorted out (for
embedding in internal memory), just need to check that my logic is
correct for playback.
  Does this sound correct; Run the PWM module at as high a rate as is
possible to make it's own frequency inaudible, and set up an interrupt
at the audio's sample rate (16kHz) to populate the duty value from the
sound array?
  I found a few different timer and PWM calculators here:
  http://eng-serve.com/pic/index.html [1]
  which looks pretty cool, I'm using a PIC18F2620 or possibly a
PIC24FJ64 in future, but from my searches the code produced should
work for them, correct?
  So to get a 16kHz interrupt (or close enough) from Timer0, with a
20MHz OSC, I should be using a 1:4 prescaler and a TMR0 preloader of
178?
  Also, according to the PWM register calculator:
  http://eng-serve.com/pic/pic_pwm.html [2]
  different values will result in different maximum duty values; if
I'm using an 8bit sound, should I simplify things by aiming for a
maximum duty value of 256 (OSC@20MHz, PWM freq @ 78kHz), or am I
missing the point?
  If I use the "full" code for setting up interrupts, PWM, etc., this
should be compatible with all C compilers, rather than using
proprietary "short" methods?  The shortcut to the compiler I'm using
says "PIC C", installed it ages ago so I'm not sure which compiler it
actually is, Hitec C, CCS, dunno?  I just know that the old projects I
have lying around used shorthand methods of setting things up, but all
of the info I've found lately on interrupts etc use the longer
methods, which I think I'm finally understanding, so should I stick to
the longer methods for cross-compiler compatability?
  Any input would be greatly appreciated
  Lee 

Links:
------
[1] http://eng-serve.com/pic/index.html
[2] http://eng-serve.com/pic/pic_pwm.html
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