SPRUIM2H May 2020 – October 2023 AM2431 , AM2432 , AM2434 , AM6411 , AM6412 , AM6421 , AM6422 , AM6441 , AM6442
The MCU_RESETz signal is the warm reset input (active low) to the entire device, controlled by the MCU_RESETz HW Pin.
When active, it resets all modules in the MCU and MAIN domains.
MCU_RESETz will not reset selected CTRLMMR_RST_CTRL and CTRLMMR_MCU_RST_CTRL register bits. These bits are only reset by PORz.
All modules in MCU domain are reset except for modules and CTRLMMR_MCU_RST_CTRL bits which are reset only on MCU_PORz.
IOs are not effected.
M4FSS is reset.
When MCU_RESETz is de-asserted, the MCU domain needs to be reconfigured by R5FSS (secondary boot loader) in the MAIN domain.
All modules in the MAIN domain are reset except for modules and CTRLMMR bits which are reset only on MAIN_PORz.
IOs are not effected.
All processor cores are reset (A53SS, DMSC-L, and R5FSS).
When MCU_RESETz is de-asserted, the device goes through full boot. The reason for this reset is captured in the CTRLMMR reset source register CTRLMMR_RST_SRC.
During device boot-up, the R5FSS (secondary boot loader) will read the CTRLMMR reset status and MCU ACTIVE MAGIC WORD registers and reconfigure the MCU domain/M4FSS processor accordingly.
MCU_RESETSTATz:
This pin indicates internal MCU_RESETz reset status (active LOW).
When LOW, it indicates that the device, both MCU and MAIN domains, are in internal reset state.
When HIGH, it indicates that the device, both MCU and MAIN domains, are out of internal reset state.
In order for the MAIN domain to come out of reset, MAIN_RESETz_REQ (RESET_REQz HW Pin) must also be de-asserted.
For more details see MCU_RESETSTATz Status Pin.