Nantonos
Senior Member

Do you have any input conditioning, filtering, squaring circuitry such as this or is the signal generator connected directly to the pin?

You are doing calculations in the linear, frequency domain: converting MIDI note to a frequency then adding a scaled offset. That will not work because perception of pitch is logarithmic, not linear. Instead convert...

Deleting a post is not helpful to others. Posting what solution you found, on the other hand, is. I assume you found that Teensy has many serial outputs and thus, sending some messages on channel 1 to one DIN MIDI...

You could have a look here: https://github.com/TeensyUser/doc/wiki/Pins Could you add a short, complete program which works on 3.6 but not on 4.x? (see forum rule).

Hi Paul! Yes, I planned to use the ordinary SPI library, with transactions.

From https://github.com/Richard-Gemmell/teensy4_i2c