【正文】 X,AL POP DX CALL DELAY。。。。。。 CALL DELAY。。。。。。 PUSH DX MOV DX,SCL MOV AL,0 OUT DX,AL POP DX CALL DELAY。。。。。。 RETSTART ENDP。停止信號STOP PROC MOV DX,I8255B MOV AL,80H 。設(shè)置8255為A端口和C端口輸出 OUT DX,AL MOV AL,00H PUSH DX MOV DX,SDA OUT DX,AL POP DX MOV AL,01H PUSH DX MOV DX,SCL OUT DX,AL POP DX CALL DELAY CALL DELAY MOV AL,01H PUSH DX MOV DX,SDA OUT DX,AL POP DX CALL DELAY CALL DELAY RETSTOP ENDP。應(yīng)答：sda低電平時間大于高電平時間ACK PROC MOV DX,I8255B MOV AL,80H 。設(shè)置8255為A端口和C端口輸出 OUT DX,AL CALL DELAY MOV AL,00H PUSH DX MOV DX,SDA OUT DX,AL POP DX CALL DELAY MOV AL,01H PUSH DX MOV DX,SCL OUT DX,AL POP DX CALL DELAY MOV AL,00H PUSH DX MOV DX,SCL OUT DX,AL POP DX CALL DELAY MOV AL,01H PUSH DX MOV DX,SDA OUT DX,AL POP DX RETACK ENDP。非應(yīng)答：NOACK PROC MOV DX,I8255B MOV AL,80H 。設(shè)置8255為A端口和C端口輸出 OUT DX,AL CALL DELAY MOV AL,01H PUSH DX MOV DX,SDA OUT DX,AL POP DX CALL DELAY MOV AL,01H PUSH DX MOV DX,SCL OUT DX,AL POP DX CALL DELAY MOV AL ,00H PUSH DX MOV DX,SCL OUT DX,AL POP DX CALL DELAY MOV AL,00H PUSH DX MOV DX,SDA OUT DX,AL POP DX RETNOACK ENDP 。按位發(fā)送數(shù)據(jù),一個字節(jié)，入?yún)LSEND PROC PUSH CX MOV CX,8 LOOP1: CALL DELAY SHL BL,1 。Bl中保存要發(fā)送的數(shù)據(jù) JC SDA1 MOV AL,00H PUSH DX MOV DX,SDA OUT DX,AL POP DX JMP NEXTSDA1: MOV AL,01H PUSH DX MOV DX,SDA OUT DX,AL POP DXNEXT: CALL DELAY MOV AL,01H PUSH DX MOV DX,SCL OUT DX,AL POP DX CALL DELAY MOV AL,00H PUSH DX MOV DX,SCL OUT DX,AL POP DX SUB CX,1 CMP CX,0 JNZ ZUO2 JMP ZUO3ZUO2: JMP LOOP1。寫完一個字節(jié)之后將SDA,SCL拉高ZUO3: MOV AL,01H PUSH DX MOV DX,SDA OUT DX,AL POP DX CALL DELAY POP CX RETSEND ENDP。按位接收數(shù)據(jù),，入?yún)I，保存至BUFFERREC[DI]RECE PROC PUSH BX PUSH CX XOR BX,BX MOV CX,8 MOV AL,01H PUSH DX MOV DX,SDA CALL DELAY OUT DX,AL 。sda=1 POP DX MOV DX,I8255B MOV AL,090H OUT DX,AL 。8255初始化，A端口輸入，C端口輸出 MOV AL,1LOOP2: SHL BH,1 。BH保存讀入的數(shù)據(jù) PUSH DX。 MOV DX,SCL。 OUT DX,AL 。scl=1 POP DX。 CALL DELAY PUSH DX xor al,al MOV DX,SDA 。讀入SAD,加到BH上 IN AL,DX POP DX AND AL,01H ADD BH,AL CALL DELAY MOV AL,00h PUSH DX MOV DX,SCL OUT DX,AL POP DX 。scl=0，sda=1 MOV AL,01h PUSH DX MOV DX,SDA OUT DX,AL CALL DELAY POP DX LOOP LOOP2 MOV BUFFERREC[DI],BH 。將讀入的數(shù)據(jù)保存至BUFFERREC[DI] POP CX POP BX RETRECE ENDP。對存儲器字節(jié)一個寫 。入?yún)DDROM，NUMWRITE PROC CALL START MOV BL,0A0H 。BL中保存的是發(fā)送命令+芯片編號+P0+W(器件地址) CALL SEND CALL ACK MOV BL,ADDROM 。BL保存存儲器內(nèi)部地址 CALL SEND CALL ACK MOV BL,NUM 。BL中保存要發(fā)送的數(shù)據(jù) CALL SEND CALL ACK CALL STOP CALL DELAY RETWRITE ENDP 。對存儲器頁寫YEWRITE PROC push cx MOV CX,COUNT1 。數(shù)據(jù)個數(shù) MOV SI,0 CALL START MOV BL,0A0H 。BL中保存的是發(fā)送命令+芯片編號+P0+W CALL SEND CALL ACK MOV BL,ADDROM CALL SEND CALL ACKLOOP5: MOV BL,BUFFERSEND[SI] CALL SEND CALL ACK CALL STOP CALL DELAY pop cx RETYEWRITE ENDP 。對存儲器字節(jié)讀 入?yún)DDROM，DI,出參保存至BUFFERREC[DI] READ PROC CALL START MOV BL,0A0H 。BL是SEND的入?yún)?BL中保存的是發(fā)送命令+芯片編號+P0+W CALL SEND CALL ACK MOV BL,ADDROM 。BL保存寄存器地址 CALL SEND CALL ACK CALL START MOV BL,0A1H 。BL中保存的是發(fā)送命令+芯片編號+P0+R CALL SEND CALL ACK MOV DI,0 CALL RECE 。入?yún)I，保存至BUFFERREC[DI] CALL NOACK CALL STOP PUSH CX MOV CX,500ting2: CALL DELAY LOOP ting2 POP CX CALL DELAY RETREAD ENDP CODE ENDSEND START146