Hello
When I was working on the S32K144-BootLoader, I was driven by this requirement:
I use the UDS protocol, when the APP receives a programming command from the diagnostics, the APP performs a soft reset and marks (BootJumpFlag = 1), Because the soft reset program starts from the beginning, the program enters the boot . the boot program detects the BootJumpflag == 1 , stay in the Boot program all the time, do not jump. Please what can I do to ensure that the BootJumpFlag does not return to zero after a soft reset.
The reference manual says register CHIPCTL SRAMU_RETE=0, SRAM_U is saved after a soft reset, SRAMU_RETE the default value is 1. How can I do this SRAMU_RETE this bit to keep the current value after a soft reset.
you can refer to S32K-RM rev13,the chapter :31.3.4 SRAM retention:power modes and resets
The SRAM data will not be lost during the software reset proces,nut will be lost during the power-down reset.The purpose of this register is to ensure that the data in the RAM cannot be accessed during the software reset process.
I suggest you use Flash area to store these flags.