I run the CAN loopback example project by NUCLEO-F446ZE. And find a problem, may I to set the r1 and r0 ? I read the RM0390, no message about it. Could you please let me know How to set the r1 & r0 bits?
I don't think you can set those bits, it looks like they are reserved by the hardware here.
Why do you need to set those ?
When I run the Extented Remote Frame and DLC is 0, I hope to set r1 & r0 to needn't  bit stuff. If I set r0 'recessive' , and DLC is 0 , there isn't  bit stuff.
Why do you want to play there ?,
R0,R1, are 'Firmware bits that are used to drive the canbus.
I find a solution to this issue. Don't care the r1 or r0 value.
When I run the Extented Remote Frame, I set the DLC is , and there isn't  bit stuff on the bit stream waveform.
Without the line drivers, I found the CanRxpin needed a pullup, or the hardware would hang on startup.
Can you receive a frame ?
Do you have a know good transmitter on a bus ?
Best to use a dongle to transmit a known good frame first, then you work on your receiver first.
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