單片機(jī)之秒表匯編程序

頻率12mhz ,從零開始計(jì)到99秒，原理為先通過十六進(jìn)制和十進(jìn)制的轉(zhuǎn)換后使用變址尋址把數(shù)據(jù)

顯示出來，十位和各位共延時(shí)4毫秒，如果有按鍵按下計(jì)數(shù)從零開始

DIZHI  EQU 21H    ;用于中間的數(shù)據(jù)傳送COUNT  EQU 22H    ;用于計(jì)數(shù)器的自加ORG    0000HJMP    STARTORG    0030HTAB:   DB 0C0H,0F9H,0A4H,0B0H,99H,92H,82H,0F8H,80H,90H  ;共陽極代碼START:  CLR    COUNTWORK1:  CALL   DISPY         ;十六進(jìn)制的轉(zhuǎn)換，輸出代碼顯示INC    COUNTJNB     P2.0 , FUYUAN ;s4按下從零開始計(jì)數(shù)MOV    A  ,COUNTCJNE   A  ,#100 ,WORK2CLR    COUNTCALL   STARTWORK2:   LJMP   WORK1DISPY:  MOV    A  ,COUNTMOV    B ,#10DIV    ABMOV    R1 ,#250    ;寄存器計(jì)數(shù)250次，一次4毫秒MOV    DIZHI  ,ADISP: MOV    A      ,DIZHI ;數(shù)據(jù)的中間交換MOV    DPTR  ,#TABMOVC    A   ,@ A+DPTR;變址尋址MOV    P0  ,A       ;P0為段選CLR     P2.5         ;P2位選，顯示十位CALL    DELSETB    P2.5MOV     A   ,BMOVC    A  , @A+DPTRMOV     P0 ,A        ;顯示個(gè)位CLR      P2.4CALL    DELSETB    P2.4DJNZ    R1  ,DISPRETFUYUAN:CALL    DELMOV      P0  ,#11111111BMOV      P2 ,#11111111BLJMP    START   ;從零開始DEL:   MOV     R6 ,#4F1:   MOV     R7, #250    ;延時(shí)兩個(gè)毫秒F2:   DJNZ     R7 ,F2DJNZ     R6 ,F1RETEND