erwieshu.asm

数字温度计 可实现4位温度数码显示.是学习单片机的一个很好的例子

;--http://www.51c51.com/BBS/dispbbs.asp?boardid=3&id=15905
   ;LED4 EQU 62H
   ;LED5 EQU 63H
   ;LED6 EQU 64H
   LED1 EQU 65H
   LED2 EQU 66H
   LED3 EQU 67H
   LED4 EQU 62H


   ORG 0000H
MAIN:  clr a
 START:

   clr a
     MOV  A,#0ffH
     CLR  C
     MOV  R2,#08H
     ;MOV R7,#02H


LOP: RLC  A       ;带C循环左移
      MOV  P2,A
      CALL DELAY
      DJNZ R2,LOP ;R2自减1非零转LOOP
      MOV  R2,#07H



LOOP1: RRC  A      ;带C循环右移
       mov  P2,A
       CALL DELAY
       DJNZ R2,LOOP1;R2自减1非零转LOOP!


FLASH:              ;闪动
       MOV P2,#0FFH
       ACALL DELAY
       MOV P2,#000H
       ACALL DELAY
       MOV P2,#0FFH
       ACALL DELAY
       MOV P2,#000H
       ACALL DELAY
       ;DJNZ R7,FLASH
       ;AJMP  START


        MOV A,#0FFH
     CLR  C
     MOV  R2,#08H
     ;MOV R7,#02H


LOP1:
      DEC A      ;减1
      RRC A     ;带C循环右移

      MOV  P2,A
      ACALL DELAY

      DJNZ R2,LOP1
      MOV  R2,#09H



LOP2:
       RL A      ;带C循环左移
        DEC A      ;减1
       mov  P2,A
       ACALL DELAY


       DJNZ R2,LOP2;R2自减1非零转LOOP!


FLASH2:              ;闪动
       MOV P2,#0FFH
       ACALL DELAY
       MOV P2,#000H
       ACALL DELAY
       MOV P2,#0FFH
       ACALL DELAY
       MOV P2,#000H
       ACALL DELAY
       ;DJNZ R7,FLASH2



   MOV DPTR,#TAB3
   ;MOV LED4,#00H
   ;MOV LED5,#00H
   ;MOV LED6,#00H
   MOV LED1,#00H
   MOV LED2,#00H
   MOV LED3,#00H
   MOV LED4,#00H

   LCALL DISPLAY
    LCALL DELAY
LOOP:
   LCALL DISPLAY
    LCALL DELAY
   INC LED1
   MOV A,LED1
   CJNE A,#10,LOOP
   CLR A


   MOV  LED1,A
   INC LED2
   LCALL DELAY
   MOV A,LED2
   CJNE A,#10,LOOP
   CLR A

   MOV LED1,A
   MOV LED2,A
   INC LED3
   LCALL DELAY
   MOV A,LED3
   CJNE A,#10,LOOP
   CLR A
      MOV LED1,A
   MOV LED2,A
   MOV LED3,A
   INC LED4
   LCALL DELAY
   MOV A,LED4
   CJNE A,#10,LOOP
   CLR A

  ;AJMP MAIN

DISPLAY:

     MOV  A,LED1
     MOVC A, @A+DPTR
     MOV SBUF,A
     JNB TI,$
     CLR TI


     MOV  A,LED2
     MOVC A, @A+DPTR
     MOV SBUF,A
     JNB TI,$
     CLR TI


     MOV  A,LED3
     MOVC A, @A+DPTR
     MOV SBUF,A
     JNB TI,$
     CLR TI


     MOV  A,LED4
     MOVC A, @A+DPTR
     MOV SBUF,A
     JNB TI,$
     CLR TI
     RET

DELAY:
   MOV R5,#40
D1:MOV R6,#70
D2:MOV R7,#70
   DJNZ R7,$
   DJNZ R6,D2
   DJNZ R5,D1
   RET
TAB3:
 DB 88H,0EBH,4CH,49H,2BH,19H,18H,0CBH,08H,09H

end