程序如下，问题就是在读的过程是完全正常，但是写的时候看FLASH区的内容没有改变的啊，怎么回事啊，我什么都没有保护哦，是在SIM的条件下仿真。



#INCLUDE<P16F877A.INC>
__CONFIG B'11111101110010'
;bit13 1=code protection off
;bit12 read as 1
;bit11 1=in-circuit debugger mode off
;bit10,9 11=flash program memory write enable
;bit8  1=data eeprom code protection off
;bit7  0=RB3 as i/o pin  lvp
;bit6  1=bor enable
;bit5,4 11=read as 11
;bit3 0=pwrt enable
;bit2 0=wdt off
;bit1,0 10=HS osc
TEMP     EQU     20H
DATA1    EQU     21H
DATA2    EQU     22H
DATA3    EQU     23H
DATA4    EQU     24H

EADRL    EQU     120H
EADRH    EQU     121H
EDATAL   EQU     122H
EDATAH   EQU     123H

ORG 0000H
GOTO MAIN
ORG 0004H
GOTO DISPOSE_INT
ORG 0005H
;--------------------------
DISPOSE_INT
RETFIE
;--------------------------
PORT_INIT
CLRW
MOVWF INTCON
MOVWF PORTA
MOVWF PORTB
BSF   STATUS,RP0
MOVWF TRISA
MOVWF TRISB
MOVLW 06H
MOVWF ADCON1
BCF   STATUS,RP0
RETLW 0
;--------------------------
MAIN
CALL  PORT_INIT
CLRW
MOVWF TEMP
BSF   STATUS,RP1
MOVLW 00
MOVWF EADRL
FLASH_READ_START
CALL  FLASH_READ
BSF   STATUS,RP1
INCF  EADRL,1
BCF   STATUS,RP1
INCF  TEMP,1
MOVLW 20H
SUBWF TEMP,0
BTFSS STATUS,Z
GOTO  FLASH_READ_START
BSF   STATUS,RP1
BCF   STATUS,RP0
MOVLW 80H
MOVWF EADRL
MOVLW 30H
MOVWF EDATAL
BCF   STATUS,RP1
MOVLW 00
MOVWF TEMP
FLASH_WRITE_START
CALL  FLASH_WRITE
BSF   STATUS,RP1
INCF  EADRL,1
BCF   STATUS,RP1
INCF  TEMP,1
MOVLW 10H
SUBWF TEMP,0
BTFSS STATUS,Z
GOTO  FLASH_WRITE_START
GOTO $
;--------------------------
FLASH_READ
BSF   STATUS,RP0
BSF   STATUS,RP1
FLASH_READ_WAIT
BTFSC EECON1,WR
GOTO  $-1
BCF   STATUS,RP0
MOVF  EADRL,0
MOVWF EEADR
MOVF  EADRH,0
MOVWF EEADRH
BSF   STATUS,RP0
BSF   EECON1,EEPGD
BSF   EECON1,RD
NOP
NOP
BCF   STATUS,RP0
MOVF  EEDATA,0
MOVWF EDATAL
MOVF  EEDATH,0
MOVWF EDATAH
BCF   STATUS,RP1
RETLW 0
;-------------------------------
FLASH_WRITE
BSF   STATUS,RP0
BSF   STATUS,RP1
FLASH_WRITE_WAIT
BTFSC EECON1,WR
GOTO $-1
BCF   STATUS,RP0
MOVF  EADRL,0
MOVWF EEADR
MOVF  EADRH,0
MOVWF EEADRH
MOVF  EDATAL,0
MOVWF EEDATA
MOVF  EDATAH,0
MOVWF EEDATH
BSF   STATUS,RP0
BSF   EECON1,EEPGD
BSF   EECON1,WREN

MOVLW 55H
MOVWF EECON2
MOVLW 0AAH
MOVWF EECON2

BSF   EECON1,WR
NOP
NOP
BCF   STATUS,RP0
BCF   STATUS,RP1
RETLW 0


END