;PIC16F877 单片机 内部EEPROM读写实例****************************************************************************************
; This is a program to test the function of reading&writting for EEPROM.
; You CAN OBServe the value of register(30H--?) buy changing "VALU" and "WRC_".
; Notice that:it must be { ADDR+WRC_<=0ffh } !
; ;****************************************************************************************
include "p16f877.inc"
ADDR EQU 20H ;写入地址寄存器
VALU EQU 21H ;写入值
REC_ EQU 22H ;读计数
WRC_ EQU 24H ;写计数
ORG 0000H ;
NOP ;放置一条ICD必须的空操作指令
GOTO main ;
;ORG 0008H ;
;org 0
;goto main
main nop
bcf STATUS,RP1
bcf STATUS,RP0 ;bank0
movlw 20h
movwf ADDR ;写入EEPROM初始值
;********************************************************************************************
clrf 8
bcf STATUS,2
DS2 nop
call DELAY
incf 8,1
movf 8,0
bcf STATUS,2
XORLW 0bh
btfss STATUS,Z
goto DS1
clrf 8
bcf STATUS,2
DS1 movf 8,0
bcf STATUS,2
call TABLE1
;***********************************************************************************************
;movlw 4fh
movwf VALU ;初始写入值
movlw 30h
movwf FSR ;间址,读出值初始存放地址
movlw 0Bh
movwf WRC_ ;写入次数
movwf REC_
;incf REC_ ;读出次数
wri_ ;写子程序
bsf STATUS,RP1
bsf STATUS,RP0 ;bank3
btfsc EECON1,WR
goto $-1
bcf STATUS,RP0
bcf STATUS,RP1 ;bank0
movf ADDR,W
bsf STATUS,RP1 ;bank2
movwf EEADR
bcf STATUS,RP1 ;bank0
movf VALU,W
bsf STATUS,RP1 ;bank2
movwf EEDATA
bsf STATUS,RP0 ;bank3
bcf EECON1,EEPGD ;to data memory
bsf EECON1,WREN
bcf INTCON,GIE
movlw 55h
movwf EECON2
movlw 0aah
movwf EECON2
bsf EECON1,WR
btfsc EECON1,WR
goto $-1
bsf INTCON,GIE
bcf EECON1,WREN
bcf STATUS,RP0
bcf STATUS,RP1 ;bank0
incf ADDR,1
;incf VALU,1
;decf VALU,1
decfsz WRC_ ;all write,to read_
;goto wri_
goto DS2
read_ ;读子程序
call TABLE1
bcf STATUS,RP1
bcf STATUS,RP0 ;bank0
decf ADDR ;next value
movf ADDR,W
bsf STATUS,RP1 ;bank2
movwf EEADR
bsf STATUS,RP0 ;bank3
bcf EECON1,EEPGD
bsf EECON1,RD
bcf STATUS,RP0 ;bank2
movf EEDATA,W
bcf STATUS,RP1 ;bnak0
movwf INDF ;存读出值
incf FSR
decfsz REC_
goto read_
goto main
;*******************************************************************************
TABLE1 ;取第二行的显示码TEL0755 27528531
ADDWF 2 ;地址偏移量加当前PC值
RETLW 30H ;0
RETLW 32H ;2
RETLW 30H ;0
RETLW 33H ;3
RETLW 33H ;3
RETLW 31H ;1
RETLW 36H ;6
RETLW 30H ;0
RETLW 30H ;0
本文关键字:单片机 PIC单片机,单片机-工控设备 - PIC单片机