FREQOUT 4mhz

[mark_s]

Those are self resonating. They will buzz at 2300hz when 5 volts is applied. Look for "transducer".

Something like this
https://www.ebay.com/itm/AT-12-Piezo...gAAOSwZd1Vewuj

[Michael]

I realized that after posting -- thanks. Will try that part you suggested. Can't believe something so simple has been such a headache.

Thanks.

[mpgmike]

Just to try a piezo to see if it works, just use the HPWM 1,127,2000 command and connect your piezo to the PWM output. I found some processors the SOUND command doesn't work so well for. I would be chasing my tail trying what you are with what I was working on.

Once you know the piezo is good for a PWM output, then work on the SOUND software. My opinion, and I reserve the right to be wrong.

[mark_s]

I realized that after posting -- thanks. Will try that part you suggested. Can't believe something so simple has been such a headache.

Thanks.

It also helps to place a 1K resistor in parallel with the transducer when driving with a logic signal. Like the others said use HPWM. Sound and Freqout are blocking commands.

[Art]

You could eliminate any doubt with the pic by oscillating port b yourself,
and connecting an LED to any of the other port b pins, and changing the delay value.

buffer var byte = 0
TRISB = 0

cycle:

if buffer == $00 then
buffer = $FF
else
buffer = $00
endif
pauseus 1
PORTB = buffer

goto cycle