PIC18F2423 MICROCHIP [Microchip Technology], PIC18F2423 Datasheet - Page 82

• Manufacturer Part Number: PIC18F2423
• Description: 28/40/44-Pin, Enhanced Flash Microcontrollers with 12-Bit A/D and nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F2423/2523/4423/4523
EXAMPLE 6-3:
DS39755B-page 80
READ_BLOCK
MODIFY_WORD
ERASE_BLOCK
Req
Seq
WRITE_BUFFER_BACK1
WRITE_BYTE_TO_HREGS1
MOVWF
MOVLW
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
TBLRD*+
MOVF
MOVWF
DECFSZ
BRA
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BCF
BSF
BSF
BCF
MOVLW
MOVWF
BSF
BSF
TBLRD*-
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVFF
MOVWF
TBLWT+*
DECFSZ
BRA
EECON2
0AAh
D’64’
COUNTER
BUFFER_ADDR_HIGH
FSR0H
BUFFER_ADDR_LOW
FSR0L
CODE_ADDR_UPPER
TBLPTRU
CODE_ADDR_HIGH
TBLPTRH
CODE_ADDR_LOW
TBLPTRL
TABLAT, W
POSTINC0
COUNTER, F
READ_BLOCK
DATA_ADDR_HIGH
FSR0H
DATA_ADDR_LOW
FSR0L
NEW_DATA_LOW
POSTINC0
NEW_DATA_HIGH
INDF0
CODE_ADDR_UPPER
TBLPTRU
CODE_ADDR_HIGH
TBLPTRH
CODE_ADDR_LOW
TBLPTRL
EECON1, EEPGD
EECON1, CFGS
EECON1, WREN
EECON1, FREE
INTCON, GIE
55h
EECON2
EECON1, WR
INTCON, GIE
BUFFER_ADDR_HIGH
FSR0H
BUFFER_ADDR_LOW
FSR0L
D’32’
COUNTER
POSTINC0,WREG
TABLAT
COUNTER
WRITE_BYTE_TO_HREGS1
WRITING TO FLASH PROGRAM MEMORY
; write 55h
; point to buffer
; Load TBLPTR with the base
; address of the memory block
; 6 LSB = '0'
; read into TABLAT, and inc
; get data
; store data
; done?
; repeat
; point to buffer
; update buffer word
; load TBLPTR with the base
; address of the memory block
; access Flash program memory
; enable write to memory
; enable Row Erase operation
; disable interrupts
; write 0AAh
; start erase (CPU stall)
; re-enable interrupts
; dummy read - decrement pointer
; point to buffer
; write first 32 bytes to Flash
; get low byte of buffer data
; present data to table latch
; short write to holding
; register using pre-increment
; loop until buffers are full
; number of bytes in erase block
; point to Flash program memory
; number of bytes in holding register
Preliminary
© 2007 Microchip Technology Inc.