I've recently brought up the CAN bus on a STM32F303 and I'm currently working on bringing it up on the F722ZE. I looked at the docs and the samples from the STM32756G_EVAL board. I was happy to see that the configuration looked pretty similar to the F303 board in that the CAN TX and RX pins are the same, i.e. PA11 and PA12 with AF9 configuration. The clocks are different but I'm using the clock configuration from the F722ZE I2C sample code so the clocks are working since the I2C is working. Unfortunately, when I try to do a CAN transmit, I get nothing on the CAN TX pin. It remains high. Likewise, when I send a packet to the F722ZE I never get a CAN receive complete callback. I'm missing something here.
Any thoughts on how the F722 needs to be programmed differently than the F303 board?