I am working on a project where I have to communicate with CAN protocol. Therefore, I bought SN65HVD230 CAN transceiver module to connect it to my STM32F429ZI Nucleo board. I am giving 3V3 from Nucleo boards 3V3 output to transceiver.
The problem is, if I scope the output of CANH and CANL the signal is not differential. I switched the IC in case it got fried during my testing but it seems to behave same. Also can't receive the signal when I connect CAN transceiver module to the CAN to USB converter (probably because signal is not differential).
I attached the screen of the scope. Blue and Yellow lines are CANH and CANL.
Edit: I also realized that Vref pin is switching with the CANH and CANL signal but in datasheet it is stated that Vref=Vcc/2. Vcc is stable 3.3V. Why would it switch with CANH and CANL.