Having trouble routing MSCAN to Pins J7-6 on the MC9S12D64. I have succeeded in getting MSCAN to work on Port M, Pins 1-0 on two other derivatives, and on J7-6 (I think) on the 256, but nothing seems to work to get MSCAN to work on J7-6 of the D64.
I'm setting MODRR=3 to route CAN0 to PJ7/PJ6. I have tried various combinations of the other Port J configuration registers (e.g., DDRJ = 0x80 or 0x00, PERJ = 0x00 or 0xC3) I also have tried to ensure that the IIC is disabled (I think, by explicitly setting IBCR = 0).
Is there some special combination of configuration bits needed to make JP7-6 work? Are there known hardware problems with the function? (This is driving me nuts.)
It sounds strange. You shouldn't need to bother with the port or IIC settings. IIC takes precedence over CAN, but only if it is enabled, and CAN takes precedence over port I/O when enabled.
Perhaps it could be a hardware problem on the board?
I suspected a hardware problem, but I detect no signal at all on the Tx line (PJ7) when I try to send a message. So it seems like a problem with the chip itself, or its configuration.
