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CAN bus accidentally swapped TX and RX is it possible to solve (in firmware) without board rework

newbie_hs

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I am interfacing an isolated can transceiver with my microcontroller.My schematic is given below.
1716910715586.png

1716910737739.png

Accidently TXD is connected to RXD of microcontroller and RXD is connected to TXD of the microcontroller.


My question can I solve this issue without any rework in the board?

May I know firmware persons can help us by doing some changes in thier code and making this interface up.

Is it possible to swap MCU CAN RX and TX in firmware.
 
Solution
Refer to S32K148_IO_Signal_Description_Input_Multiplexing.xlsx (Reference manual attachment), it gives a complete list of available multiplex settings for peripheral connection. Swapping CAN RX and TX isn't provided.
I am interfacing an isolated can transceiver with my microcontroller.My schematic is given below.
View attachment 191125
View attachment 191126
Accidently TXD is connected to RXD of microcontroller and RXD is connected to TXD of the microcontroller.


My question can I solve this issue without any rework in the board?

May I know firmware persons can help us by doing some changes in thier code and making this interface up.

Is it possible to swap MCU CAN RX and TX in firmware.
Not without reworking the board No. But quite conveniently Removing R353, R352 will disconnect/break the txd and rxd to allow you to use a axial resistor to cross the lines over without significant rework
 
I don't know what microcontroller you are using or if the serial routines use interrupts.
You can sometimes use serial bit bang routines to communicate with the controller while changing the TX and RX pins in the software.
 
Refer to S32K148_IO_Signal_Description_Input_Multiplexing.xlsx (Reference manual attachment), it gives a complete list of available multiplex settings for peripheral connection. Swapping CAN RX and TX isn't provided.
 
Solution

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