SPRUJB3 March 2024 AM67 , AM67A , TDA4AEN-Q1 , TDA4VEN-Q1
The RTC provides eight general-purpose registers (SCRATCHx_REG) that can be used to store 32-bit words -- these registers have no functional purpose for the RTC. Software using the RTC may find the SCRATCHx registers to be useful in indicating RTC states. For example, the SCRATCHx_REG registers may be used to indicate write-protection lock status or unintentional power downs. To indicate write-protection, the software should write a unique value to one of the SCRATCHx_REG registers when write-protection is disabled and another unique value when write-protection is enabled again. In this way, the lock-status of the registers can be determined quickly by reading the SCRATCH register. To indicate unintentional power downs, the software should write a unique value to one of the SCRATCHx_REG registers when RTC is configured and enabled. If the RTC is unintentionally powered down, the value written to the SCRATCH register is cleared. For more information, see RTCSS Registers.