SPRUIM2H May 2020 – October 2023 AM2431 , AM2432 , AM2434 , AM6411 , AM6412 , AM6421 , AM6422 , AM6441 , AM6442
The entering in Power Down mode is controlled via two sources:
As long as the clock stop request signal is active, the MCAN_CCCR[4] CSR bit is read as 1.
When all pending transmission requests have completed, the MCAN module waits until bus idle state is detected. Then the MCAN module sets the MCAN_CCCR[0] INIT bit to 1 to prevent any further CAN transfers.
The MCAN module acknowledges that it is ready for power down:
In this state, before the clocks are switched off, further register accesses can be made. Now the module clock inputs ICLK and FCLK may be switched off.
To leave power down mode, the application has to turn on the module clocks before resetting the input clock stop request signal respectively the MCAN_CCCR[4] CSR flag bit. The MCAN will acknowledge this by resetting the output clock stop acknowledge signal respectively the MCAN_CCCR[3] CSA flag bit. Afterwards, the application can restart CAN communication by resetting the MCAN_CCCR[0] INIT bit.
Restoring the clocks from clock stop mode, needs to be done according to how the clock stop was initiated: