Datasheet

 2010 Microchip Technology Inc. DS39969B-page 85
PIC24FJ256DA210 FAMILY
EXAMPLE 5-2: ERASING A PROGRAM MEMORY BLOCK (‘C’ LANGUAGE CODE)
EXAMPLE 5-3: LOADING THE WRITE BUFFERS
EXAMPLE 5-4: INITIATING A PROGRAMMING SEQUENCE
// C example using MPLAB C30
unsigned long progAddr = 0xXXXXXX; // Address of row to write
unsigned int offset;
//Set up pointer to the first memory location to be written
TBLPAG = progAddr>>16; // Initialize PM Page Boundary SFR
offset = progAddr & 0xFFFF; // Initialize lower word of address
__builtin_tblwtl(offset, 0x0000); // Set base address of erase block
// with dummy latch write
NVMCON = 0x4042; // Initialize NVMCON
asm("DISI #5"); // Block all interrupts with priority <7
// for next 5 instructions
__builtin_write_NVM(); // check function to perform unlock
// sequence and set WR
; Set up NVMCON for row programming operations
MOV #0x4001, W0 ;
MOV W0, NVMCON ; Initialize NVMCON
; Set up a pointer to the first program memory location to be written
; program memory selected, and writes enabled
MOV #0x0000, W0 ;
MOV W0, TBLPAG ; Initialize PM Page Boundary SFR
MOV #0x6000, W0 ; An example program memory address
; Perform the TBLWT instructions to write the latches
; 0th_program_word
MOV #LOW_WORD_0, W2 ;
MOV #HIGH_BYTE_0, W3 ;
TBLWTL W2, [W0] ; Write PM low word into program latch
TBLWTH W3, [W0++] ; Write PM high byte into program latch
; 1st_program_word
MOV #LOW_WORD_1, W2 ;
MOV #HIGH_BYTE_1, W3 ;
TBLWTL W2, [W0] ; Write PM low word into program latch
TBLWTH W3, [W0++] ; Write PM high byte into program latch
; 2nd_program_word
MOV #LOW_WORD_2, W2 ;
MOV #HIGH_BYTE_2, W3 ;
TBLWTL W2,
[W0] ; Write PM low word into program latch
TBLWTH W3,
[W0++] ; Write PM high byte into program latch
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; 63rd_program_word
MOV #LOW_WORD_63, W2 ;
MOV #HIGH_BYTE_63, W3 ;
TBLWTL W2,
[W0] ; Write PM low word into program latch
TBLWTH W3,
[W0] ; Write PM high byte into program latch
DISI #5 ; Block all interrupts with priority <7
; for next 5 instructions
MOV.B #0x55, W0
MOV W0, NVMKEY ; Write the 0x55 key
MOV.B #0xAA, W1 ;
MOV W1, NVMKEY ; Write the 0xAA key
BSET NVMCON, #WR ; Start the programming sequence
NOP ; Required delays
NOP
BTSC NVMCON, #15 ; and wait for it to be
BRA $-2 ; completed