arms22

Would you like to add a transistor? like this http://cyberworks.cocolog-nifty.com/blog/files/modem_mono.pdf

Yes. An analog comparator becomes unnecessary. There should be an interrupt pin for reception and a general-purpose pin for transmissions.

I think that additional circuitry is necessary to support SoftModem. https://github.com/arms22/SoftModem/issues/5#issuecomment-240717423

ATmega32U4 has Analog Comparator. AIN+ can be connected either to the AIN0 (PE6) pin, or to the internal Bandgap reference. AIN- can only be connected to the ADC multiplexer. If...

I have attached a video. Please note that it might be difficult to hear on some speakers. https://github.com/user-attachments/assets/22a38457-f3e1-4df6-9a8d-104b569c4560 https://github.com/user-attachments/assets/67bb8630-5b98-4379-9b98-5ac135d41f6c

Changing the following eliminated the noise: `driver.voltage_limit = 6 -> 8;` However, changing the following caused noise: `motor.voltage_limit = 3-> 4;` I suspect that the PWM waveform may be distorted...

I checked the PWM waveform, but did not find any issues. The attached image shows the PWM waveforms of the A/B outputs. The noise occurred precisely when the light blue...

Thank you for sharing the relevant links. It seems that Ua, b, c are saturated and exceeding the maximum value.