8279qq.asm

8279与单片机接口 8279与单片机接口 8279与单片机接口

 ORG 0000H				
   AJMP MAIN
   ORG 0003H
   AJMP INSER
   MAIN:
   MOV DPTR,#7000H                  //初始化
   INC DPTR 
   MOV A, #00H                     
   MOVX @DPTR,A
   MOV A , #0D1H 
   MOVX @DPTR, A				   
   MOV A , #28H
   MOVX @DPTR , A 
   INSER:

   MOV DPTR ,#7001H               //读入键盘状态
   MOVX A , @DPTR                                              
   ANL A , #07H                     //判断是否有键按下
   CJNE A , #00H,LOOP2     
   RETI
   LOOP2:
   MOV DPTR ,#7000H            
   MOVX A,@DPTR                     //取出行列号
   anl a,3fh
   PUSH A
   LOOP1:
   MOV DPTR,#7001H
   MOVX A , @DPTR
   JB ACC.7 ,LOOP1
   MOV A , 80H 
   MOVX @DPTR , A
   POP A

   MOV DPTR ,#7000H
   MOVX @DPTR , A
   
   inc DPTR
   MOVX A,@DPTR
   ANL A , #07H
   CJNE A , #00H,LOOP3
   RETI
   LOOP3:  
   MOV A,11000010B
   MOVX @DPTR,A
   MOV A, #00H
   MOVX @DPTR,A
   MOV A , #0D1H 
   MOVX @DPTR, A				   
   MOV A , #28H
   MOVX @DPTR , A 
   MOVX A,@DPTR
   ANL A , #07H
   CJNE A , #00H,LOOP3
   RETI