Thank you
I really appreciate you input
I did it this way as I was following what another person suggested.
https://forum.arduino.cc/index.php?topic=346731.15
He explained the multiplexer is grouped in pairs
so my understanding is I was thinking of
D5, which is PA5
D6, which is PA4
actually I used
PA10, which is A3
PA11, which is A2
and this does work I get PWM on these pins as I expected but yes I got confused thank you for that.
RE Wave output pin it seems from reading the data sheet on page 28 for example for the pins above
arduino nano 33 IOT is a samd 21 G variant
A3 PA10 on F peripheral is TCC0/ WO[2]
A2 PA10 on F peripheral is TCC0/ WO[3]
I am not sure where to go from here
I thought the type of wave form generation was done in configuration, with these lines
// Dual slope PWM operation: timers countinuously count up to PER register value then down 0
REG_TCC0_WAVE |= TCC_WAVE_POL(0xF) | // Reverse the output polarity on all TCC0 outputs
TCC_WAVE_WAVEGEN_DSBOTTOM; // Setup dual slope PWM on TCC0
while (TCC0->SYNCBUSY.bit.WAVE); // Wait for synchronization
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