8279qqs.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	sp,#60h
start:   MOV DPTR,#0f800H                  //初始化
   INC DPTR 
   MOV A, #00H                     
   MOVX @DPTR,A
   MOV A , #0D3H 		   //;清显示
   MOVX @DPTR, A				   
   MOV A , #28H				  //clock
   MOVX @DPTR , A 
   setb	EA
   setb EX0


   MOV DPTR ,#0ff01H  
   MOV A , #0D2H 		   //;清显示
   MOVX @DPTR, A
  
   MOV A , #90H 					  //write ram
   MOVX @DPTR , A


   mov	a,#04h
   MOV DPTR ,#0ff00H
   MOVX @DPTR , A

      MOV A , #91H 					  //write ram
   MOVX @DPTR , A


   mov	a,#0f2h
   MOV DPTR ,#0ff00H
   MOVX @DPTR , A

   ljmp	start


   INSER:
   clr 	EA
   
   MOV DPTR ,#0ff01H               //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 ,#0ff00H            
   MOVX A,@DPTR                     //取出行列号
   anl a,3fh
   mov	40h,a
   PUSH 40h

   inc DPTR
   MOV A , #0D2H 		   //;清显示
   MOVX @DPTR, A


   LOOP1:
   MOV DPTR,#0ff01H				   
   MOVX A , @DPTR
   JB ACC.7 ,LOOP1
   MOV A , #80H 					  //write ram
   MOVX @DPTR , A
   POP 40h
   mov	a,#04h
   MOV DPTR ,#0ff00H
   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
      
   end