Question
NUCLEO-L496, STLINK-V3 problem with bootloader CAN
Hello everyone!
I read many topics on this forum and it is really helpful but currently I try to solve my problem - unsuccesfully.
What I want to do: program MPU through bootloader CAN
Hardware: NUCLEO-L496, STLINK-V3. Crystal HSE soldered on NUCLEO (AN2606). Common GND, CAN_VCC connected to 3,3V. CAN bus on PB8 and PB9
Bits BOOTn are set by means of SWD. Bootloader is running - checked in MPU Core.
- When connect CAN TX and RX (NUCLEO and STLINK) directly - without CAN transceivers - STM32CubeProgrammer connect with STM correctly and it can be programmed. I made sure that bootloader work properly but that is not the point.
- When connect NUCLEO > transceiver, STLINK>transceiver and to the CAN bus then signal from NUCLEO to STLINK (STM_RX STM_TX, CANH CANL, STLINK_RX STLINK_TX) is transmitted through all 'levels' (checked on logic analyzer). If signal is sent from STLINK - it has correct form (CAN RX and TX) without connection to transceiver. If connect to transceiver - no signal. I checked by means of logic analyzer and all lines(STM_RX STM_TX, CANH CANL, STLINK_RX STLINK_TX) are in HIGH state, no changes.
My device is connect to CAN bus and I need to program it from bus - I don't have a physical access to CAN RX and CAN TX from MPU.
It seems to be problem (electronic?) is on line transceiver - programmer. Maybe it is bug with STLINK or CubeProgrammer? Anyone has a similar problem and can help?
Michal