spi-send.asm

PIC16F873模拟的SPI发送程序

;双机通信之单接受单片机，接受来自发送方的数据，并把其送到D口显示
         LIST  P=16F877
         INCLUDE<P16F877.INC>
       
        W_TEMP    EQU     7FH
        ORG   0X00
        GOTO  MAIN
;中断程序
        ORG   004H
JEISHOU MOVWF  W_TEMP
        BCF    PIR1,SSPIF
        MOVF   SSPBUF,0
        BCF    PIR1,SSPIF
        MOVF   SSPBUF,0
        BCF    STATUS,RP0
        MOVWF  PORTD
        movlw    0xff
        movwf     77h
lp0     movlw    0xff
        movwf     78h
lp1     movlw    0xff
        movwf     79h      
lp2     nop
        nop 
        nop
        nop 
        nop
        decfsz    78h,1
        goto      lp2
        decfsz    77h,1
        goto      lp1
        decfsz    79h,1
        goto      lp0
        MOVF      W_TEMP,W
        RETFIE
        


;SPI的初始化，即相关寄存器的设置
MAIN    BCF  STATUS,RP1           ;在体1里面设置TRISC和SSPSTAT
        BSF  STATUS,RP0
        MOVLW  0X18
        MOVWF  TRISC
        MOVLW  0X00
        MOVWF  TRISD   
      
        BCF    TRISE,4
        MOVLW  0X0F
        MOVWF  ADCON1        
        BSF    TRISA,5
        MOVLW  0X00 
        MOVWF  SSPSTAT
        BCF    STATUS,RP0        ;在体0里面设置SSPCON，从机的工作于从动方式,时钟等于SCK,从动选择引脚势能
        CLRF   PORTD
        MOVLW  0X40
        MOVWF  SSPCON
        BSF    INTCON,7          ;开全局中断
        BCF    PIR1,SSPIF
        BSF    PIE1,SSPIE
        


        end