28.2.79 __builtin_write_NVM_secure

Description

Enables the Flash for writing by issuing an unlock sequence specified by two keys and enabling the Write bit of the NVMCON register. After completion, the two keys are cleared to zero.

Interrupts may need to be disabled for proper operation.

This builtin function can be used as a part of a complex sequence discussed in your device data sheet or Family Reference Manual (FRM). See these documents for more information.

Prototype

void __builtin_write_NVM_secure(uint16_t key1, uint16_t key2);

Arguments

key1 – first key in the NVM unlock sequence

key2 – second key in the NVM unlock sequence

Return Value

None

Example Instruction sequence

   mov  w0, _NVMKEY
   nop
   mov  w1, _NVMKEY
   bset _NVMCON,#15
   clr  w0
   clr  w1

Error Messages

None