0809_ok.asm

51单片机实现A/D转换

; 使用  0809做AD转换  串口输出转换后值
;频率：11.0592M，A/D地址：6800
   ORG       0000H
             LJMP      START


         ORG       0050H
   START:MOV       SP,#30H
;******************************
;       MEMORY INITIALIZE
;******************************
         CLR EA
         MOV       R0,#40H
MEM_INI:MOV      @R0,#55H
         INC       R0
         CJNE      R0,#80H,MEM_INI

         MOV       TMOD,#20H
         MOV TH1,#0FDH       ;F=11.0592M
         MOV TL1,#0FDH       ;F=9600
         MOV SCON,#0D0H;MOD3
         MOV PCON,#00H
         SETB TR1

           CALL DEL6
         MOV SBUF,#0F0H
            CALL DEL6
            MOV SBUF,#55H
            CALL DEL6
            MOV SBUF,#0FFH
            CALL DEL6



            MOV       A,#55H
  L_END:   ; JB       RI,RECEIVE    :串口有输入
            CALL     DEL1S
            CALL     JISUAN    ;CALL AD
            MOV      SBUF,A
            JMP L_END

JISUAN:     MOV A,#00H
            MOV R0,A
            MOV R1,#07H
       ADD10:CALL DEL6
            CALL AD
            MOV SBUF,A
            ADD A,R0
            MOV R0,A
            DJNZ R1,ADD10
            RET

AD:MOV	DPTR,#6800H
	MOV	A,#00H
	MOVX	@DPTR,A
	LCALL	DEL6	;延时0.13MS
	MOVX	A,@DPTR
        RET
RECEIVE:

            CALL DEL6
            MOV A,SBUF
            INC A
            MOV SBUF,A
            CALL DEL6
            CLR RI
JMP L_END



;**********DELAY 1S**********
   DEL1S:MOV       R6,#0FFH
     DLA:MOV       R5,#0FFH
     DLB:MOV       R4,#0AH        ;256x256x5x3=1s
     DLC:NOP
         DJNZ      R4,DLC
         DJNZ      R5,DLB
         DJNZ      R6,DLA
         RET


;**********DELAY 6ms**********
    DEL6:          ;DELAY 6ms
         SETB      PSW.3
         SETB      PSW.4
         MOV       R7,#12
   DEL61:MOV       R6,#250
   DEL62:DJNZ      R6,DEL62
         DJNZ      R7,DEL61
         MOV PSW,A
         RET

END