After 2 days of asking why, Why, WHY, WHY?!?!?!  I finally stepped back and
realized I forgot the pull-up resistor on RA4 which I'm using for the
Data/Instruction line.  So, it thought every bit of data I was sending was
an instruction.

Anyway, now I've got a 128x64 graphics LCD from CrystalFontz displaying 3
animated, 4-pixel balls bouncing around the screen.  The completely
un-optimized code takes up 783 words and runs at 20fps.  I had to slow it
down because the 60fps speed was making it impossible to see the balls.  It
still updates the positions 60 times/sec, but only re-draws the balls every
3rd frame.

So, on to performance testing...  I'm using the internal 4MHz clock and the
RTCC interrupt at DIV_BY_64.  This gives me approximately 61 interrupts/sec.
I was curious how hard I was driving this little chip, so I had it turn a
pin HIGH at the start of the interrupt and LOW when it finished.  Out of the
16ms per calculation, only 3ms is used to update the positions and redraw
the balls.  On a calculate only cycle, about 1ms is used.  So, that equates
to only 12.5% CPU usage!  (6ms used / 48ms per frame = 12.5%)

Now for some paddles and a collision detection routine... :)  Oh, and some
user input!

Barry

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