I have also been finding some CANbus issues on powerup. I have been finding similar quirks which cause system wide boot up to cause issues because the pycom module does not always work on the bus. Sometimes this also seems to cause faults for other system. I will be adding 10k pull up and pull downs in my design to help mitigate startup and reprogramming issues. What is the weak pull down resistors? I am guessing between 47k and 100k

Hi, A firmware with the CAN library has just been released and the documentation for it is available here: https://docs.pycom.io/chapter/firmwareapi/pycom/machine/CAN.html