Hi Brent,

> Send triangle or sawtooth wave data to the DAC to see
> if glitch still appears

Yeah, no matter what the waveform it doesn't go away

Instead of using the ADC result as the data I've added the middle
line here to send a constant to the DAC

           mov     ADC1BUF0,w0
           mov     #0x0800,w0              ;substitute 0x0800 for ADC resul=
t
           mov     w0,[w8++]

No change. So I *think* that rules out the ADC as the cause and
I'm leaning towards it being somewhere in the DAC. That "Timer1
period x 1024" thing might be something to do with it or just a red
herring coincidence

> Change timer speed and observe if it affects glitch

If you alter the main oscillator (eg with OSCTUN), the glitch spacing
tracks it. Timer1 and the DAC oversampling are tied to the PLL
frequency, Fvco. ie sampling and recreation must be in a particular
ratio. If you change Timer1 reload by even 1, the DAC output changes
drastically for the worse, the cycles equation doesn't balance anymore.

And the glitch will still be there ;-))

Joe=20



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