16.5.5 Boot Failure Signal

The Boot ROM provides a mechanism to indicate boot failure through a user-configurable Boot Failure Signal, enabled through the BOOT_GPIOSEL fuse located in the BOOTCFG1/1A region.

Users can select a specific I/O pin to serve as the fault indicator for their application. If a boot failure occurs (for example, CRC check failure on FME), the Boot ROM asserts the selected I/O pin to signal the fault condition.

Note: By default, the Boot Failure Signal is disabled (BOOT_GPIOSEL = NONE). To enable this feature, users must program the BOOT_GPIOSEL fuse with a valid I/O selection. Refer to the Fault Signal Configuration for additional information on available I/O options and configuration guidelines.

Important: Once the Boot ROM transfers control to the first mutable application code, it no longer manages or controls the fault signal pin. The application firmware is responsible for any further handling or de-assertion of the signal.