INCLUDE ;同样可用于其他型号

;*************************定义变量************************
                        STATUS   EQU 3H
                        PORTB    EQU 6H
                        PORTC    EQU 7H
                        EEPROM   EQU 08H
                        ADDR     EQU 09H
                        BUFIN    EQU 0AH
                        BUFOUT   EQU 0BH
                        SLAVE    EQU   0CH
                        TXBUF    EQU   0DH
                         BIT       EQU    0EH
                        DLY1     EQU   0FH
                        DLY2     EQU   10H
                         DI       EQU      7
                         DO       EQU     6
                         SDA      EQU    7
                         SCL      EQU    6
                         ACKF     EQU   0
;**********************程序开始***************************
       ORG    7FFH
       GOTO   MAIN
       ORG    000H
;**********************启动信号***************************************
BSTART 
       BSF    PORTB,SDA
       BSF    PORTB,SCL 
       MOVLW  B'00111111'
       TRIS   PORTB
       NOP
       NOP
       NOP
       NOP
       NOP
       NOP
       BCF    PORTB,SDA
       NOP
       NOP
       NOP
       NOP
       NOP
       BCF    PORTB,SCL
       NOP
       NOP
       RETLW  0
;***********************停止信号********************************
BSTOP
       BCF    PORTB,SDA
       MOVLW  B'00111111'
       TRIS   PORTB
       BCF    PORTB,SDA
       NOP
       NOP
       NOP
       BSF    PORTB,SCL
       NOP
       NOP
       NOP
       BSF    PORTB,SDA
       NOP
       NOP
       BCF    PORTB,SCL
       NOP
       NOP
       RETLW  0
;**********************发送一个字节**************************
TX     
       MOVLW  D'8'
       MOVWF  BIT
TXLP   BCF    EEPROM,DO
       BTFSC  TXBUF,7
       BSF    EEPROM,DO
       CALL   BITOUT
       RLF    TXBUF
       DECFSZ BIT
       GOTO   TXLP
       CALL   BITIN
       BTFSC  EEPROM,DI
       BSF    PORTC,ACKF
       RETLW  0
;************************接收一个字节*****************************
RX
       CLRF   BUFIN
       MOVLW  D'8'
       MOVWF  BIT
       BCF    STATUS,0
RXLP   RLF    BUFIN
       BCF    BUFIN,0
       CALL   BITIN
       BTFSC  EEPROM,DI
       BSF    BUFIN,0
       DECFSZ BIT
       GOTO   RXLP
       BSF    EEPROM,DO
       CALL   BITOUT
       RETLW  0
;**********************发送********************************
BITOUT
       MOVLW   B'00111111'
       tris    PORTB
       BTFSS   EEPROM,DO
       GOTO    BITLOW
       BSF     PORTB,SDA
       GOTO    CLKOUT
BITLOW BCF     PORTB,SDA
CLKOUT BSF     PORTB,SCL
       NOP
       NOP
       NOP
       NOP
       BCF     PORTB,SCL
       RETLW   0
;**********************接收****************************
BITIN
       BSF     EEPROM,DI
       MOVLW   B'10111111'
       TRIS    PORTB
       BSF     PORTB,SCL
       NOP
       NOP
       NOP
       NOP
       NOP
       BTFSS   PORTB,SDA
       BCF     EEPROM,DI
       BCF     PORTB,SCL
       RETLW   0
;***********************主程序**********************
MAIN
       MOVLW  B'00000000'
       TRIS   PORTC
       CLRF   PORTC
WRITE                                 ;写存储器
       CLRF   PORTC
       MOVLW  B'10100000'
       MOVWF  SLAVE
       MOVLW  B'10101010'
       MOVWF  BUFOUT
       CLRF   ADDR
LOOP0  CALL   BSTART
       MOVF   SLAVE,0
       MOVWF  TXBUF
       CALL   TX
       MOVF   ADDR,0
       MOVWF  TXBUF
       CALL   TX
       MOVF   BUFOUT,0
       MOVWF  TXBUF
       CALL   TX
       CALL   BSTOP
DELAY10MS
       MOVLW  D'13'
       MOVLW  DLY1
       MOVLW  0FFH
       MOVWF  DLY2
LP0    DECFSZ DLY2
       GOTO   $-1
       DECFSZ DLY1
       GOTO   $-5
READ                                ;读存储器
       CLRF   PORTC
       MOVLW  B'10100000'
       MOVWF  SLAVE
       CLRF   ADDR
LOOP1  CALL   BSTART
       MOVF   SLAVE,0
       MOVWF  TXBUF
       CALL   TX
       MOVF   ADDR,0
       MOVWF  TXBUF
       CALL   TX
       CALL   BSTART
       MOVLW  B'10100001'
       MOVWF  TXBUF
       CALL   TX
       CALL   RX
       CALL   BSTOP
       NOP
       NOP
       NOP
       NOP
       NOP
       NOP
       MOVF   BUFIN,0
       MOVWF  PORTC
LOOP2  NOP
       GOTO   $-1
;************************
       END