PIC18F258 MICROCHIP [Microchip Technology], PIC18F258 Datasheet - Page 74

• Manufacturer Part Number: PIC18F258
• Description: High Performance, 28/40-Pin Enhanced FLASH Microcontrollers with CAN
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18FXX8
EXAMPLE 6-3:
DS41159B-page 72
READ_BLOCK
MODIFY_WORD
ERASE_BLOCK
Required
Sequence
WRITE_BUFFER_BACK
PROGRAM_LOOP
WRITE_WORD_TO_HREGS
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
TBLRD*+
MOVF
MOVWF
DECFSZ COUNTER
BRA
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BCF
BSF
BSF
BCF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
NOP
BSF
TBLRD*-
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVFW
MOVWF
TBLWT+*
DECFSZ COUNTER
BRA
WRITING TO FLASH PROGRAM MEMORY
D’64
COUNTER
high (BUFFER_ADDR)
FSR0H
low (BUFFER_ADDR)
FSR0L
upper (CODE_ADDR)
TBLPTRU
high (CODE_ADDR)
TBLPTRH
low (CODE_ADDR)
TBLPTRL
TABLAT, W
POSTINC0
READ_BLOCK
DATA_ADDR_HIGH
FSR0H
DATA_ADDR_LOW
FSR0L
NEW_DATA_LOW
POSTINC0
NEW_DATA_HIGH
INDF0
upper (CODE_ADDR)
TBLPTRU
high (CODE_ADDR)
TBLPTRH
low (CODE_ADDR)
TBLPTRL
EECON1,EEPGD
EECON1,CFGS
EECON1,WREN
EECON1,FREE
INTCON,GIE
55h
EECON2
AAh
EECON2
EECON1,WR
INTCON,GIE
8
COUNTER_HI
high (BUFFER_ADDR)
FSR0H
low (BUFFER_ADDR)
FSR0L
8
COUNTER
POSTINC0, W
TABLAT
WRITE_WORD_TO_HREGS
Preliminary
; number of bytes in erase block
; point to buffer
; Load TBLPTR with the base
; address of the memory block
; 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
; point to FLASH program memory
; access FLASH program memory
; enable write to memory
; enable Row Erase operation
; disable interrupts
; write 55H
; write AAH
; start erase (CPU stall)
; re-enable interrupts
; dummy read decrement
; number of write buffer groups of 8 bytes
; point to buffer
; number of bytes in holding register
; get low byte of buffer data
; present data to table latch
; write data, perform a short write
; to internal TBLWT holding register.
; loop until buffers are full
 2002 Microchip Technology Inc.