PIC32MX440F256H-80I Datasheet, PDF (124/646 Pages) Microchip Technology – 64/100-Pin General Purpose and USB 32-Bit Flash Microcontrollers

PIC32MX3XX/4XX
EXAMPLE 7-3: WORD PROGRAMMING SEQUENCE
unsigned int NVMUnlock (unsigned int nvmop)
{
unsigned int status;
// Suspend or Disable all Interrupts
asm volatile (“di %0” : “=r” (status));
// Enable Flash Write/Erase Operations and Select
// Flash operation to perform
NVMCON = nvmop;
// Write Keys
NVMKEY = 0xAA996655;
NVMKEY = 0x556699AA;
// Start the operation using the Set Register
NVMCONSET = 0x8000;
// Wait for operation to complete
while (NVMCON & 0x8000);
// Restore Interrupts
if (status & 0x00000001
asm volatile (“ei”);
else
asm volatile (“di”);
// Return NVMERR and LVDERR Error Status Bits
return (NVMCON & 0x3000)
}
unsigned int NVMWriteWord (void* address, unsigned int data)
{
unsigned int res;
// Load data into NVMDATA register
NVMDATA = data;
// Load address to program into NVMADDR register
NVMADDR = (unsigned int) address;
// Unlock and Write Word
res = NVMUnlock (0x4001);
// Return Result
return res;
}
DS61143E-page 122
Preliminary
© 2008 Microchip Technology Inc.