Hi, I am Wang He. Now I am Using MPC5606B to manage 6ch CAN bus. Can3 Rx electrical level is not normal while the other 5ch CAN bus are normal.
Can3 Rx wave form is like this:
Low level is 2V, not 0V, while the other 5ch CAN bus Rx is 0V.
Schematic is like this:(the 6ch CAN bus are same)
The configuration of CAN3 is different from the other 5ch CAN bus is:
SIU.PCR[36].R = 0x0101;
SIU.PCR[37].R = 0x0A01;
For eaxmple, CAN4's configuration is like this:
SIU.PCR[94].R = 0x0601;
SIU.PCR[95].R = 0x0101;
I am looking forward to your guide. THANK You very much!
Hi,
Try to swap 2 digital isolators to check if the issue is really due to PC[4] pin or external HW. What is the signal on transceiver's RXD3 output?
Also be sure there is nothing else connected to the PC[4] pin and finally check the PCR[36] is not modified from your setting.
BR, Petr
Hi,
Thank you for your reply.
Digital isolator of CAN3 is normal(I have swaped ). The waveform on Transceiver's RXD3 and isolator's RXD are nomal also.
I am very curious. What problems can cause the waveform.(Low level is 2V, not 0V)
I did a quick test with CAN_3 module on TRK-MPC5606B and have no issue. RX pin (PC4) has normal levels.
Try to use different pin for CAN3RX, PE[9] or PF[9]) if those are not used.
BR, Petr