Microchip Technology DM240015 Data Sheet

 2012-2013 Microchip Technology Inc.

DS30009312B-page 95

// 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

•
•
•

; 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