Why CAN Bus (J1939) of STM32F405RGT is not working at vehicle's J1939 speed(250kbps) ?

[vishwakarma]

i am making a J1939 data logger with STM32F405RGT. The vehicle's J1939 is transmitting data on 250kbps, but when i set250kbps in mcu it doesnot show any data on uart terminal , but when i set 500kbps in mcu then it shows some data on UART terminal.

I am using STM32CubeIDE and generated code using CubeMX. The Same firmware that has CAN configured at 250kbps receives data from a CAN Simulator.

[waclawek.jan]

Are you sure J1939 is compatible with CAN?

JW

[Ozone]

It basically is - J1939 is based on CAN.

> ... but when i set250kbps in mcu it doesnot show any data on uart terminal ,

What is that supposed to mean ?

CAN and UART/RS232 are definitely not compatible.

[vishwakarma]

I am using UART Only for debugging purpose....

I have configured CAN Receive Interrupt and in Interrupt Handler i am transmitting that data back to UART so that I can see it.