倒计时器设计 汇编.docx

采用51单片机机型设计可实现输入、倒计时、暂停功能适合北京理工大学单片机课程作业参考.ORG 0000HMOV P1,#3FH ;初始显示000AJMP MAINORG 001BHAJMP DENGORG 000BHAJMP JISHIORG 0030HMAIN:MOV TMOD,#11HMOV TH1,#0DFHMOV TL1,#0FFH;T1控制灯亮间隔SETB TR1SETB EASETB ET1MOV P3,#04HCHUSHI:MOV 30H,#3FH; 个位MOV 31H,#3FH; 十位MOV 32H,#3FH; 百位MOV 34H,#00H;暂存MOV 35H,#00H;控制是否有按键间隙MOV 37H,#00HMOV 38H,#00H;是否开始倒计时MOV 40H,#01H ;对应 30H 存数码管显示MOV 41H,#01H MOV 42H,#01H MOV 50H,#00H;对应 30H 存第几 1 2 3.MOV 51H,#00HMOV 52H,#00HTEST:MOV P0,#0F0H ;判断输入数值MOV A,P0ANL A,#0F0H CJNE A,#0F0H,HAVEMOV 35H,#01H;有间隔 35H 置1SJMP TESTHAVE:MOV A,#0FEHNEXT:MOV B,AMOV P0,AREAD:MOV A,P0ANL A,#0F0HCJNE A,#0F0H,YES MOV A,BRL A CJNE A,#0EFH,NEXTYES:ACALL DAYAREAD:MOV A,P0ANL A,#0F0H MOV R2,A MOV A,B ANL A,#0FH ORL A,R2 YES1:MOV R1,AMOV R0,#0 MOV DPTR,#TAB1SJMP CMKEY DAY:MOV R6,#20;延时DL2:MOV R7,#7DHDL1:NOPNOPDJNZ R7,DL1DJNZ R6,DL2RET CMKEY:MOV A,R0 MOVC A,A+DPTRCLR C SUBB A,R1 JZ DISP INC R0 MOV A,#10H SUBB A,R0JZ TESTSJMP CMKEYDISP:MOV A,38H;判断是否开始计时了CJNE A,#01H,NORMALMOV A,35HCJNE A,#01H,NORMALMOV DPTR,#TAB2MOV A,R0 CJNE A,#0FH,BACK1;判断是否为 15 （暂停）CLR TR0;暂停，则关闭计时CLR ET0MOV 38H,#00HAJMP BACK1NORMAL:MOV DPTR,#TAB2 ;显示程序段MOV A,R0 MOV 37H,A CJNE A,#0BH,GO;输入是否为 11 （倒计时）MOV 38H,#01H;倒计时开始MOV TH0,#3CHMOV TL0,#0BHSETB ET0SETB EAMOV R4,#0AH MOV 35H,#00HSETB TR0AJMP TESTGO:MOVC A,A+DPTR;不倒计时MOV 34H,A;暂存于34HMOV R0,40HMOV R1,41HMOV R2,42HMOV A,35HCJNE A,#00H,BIJIAOAJMP BACK1BIJIAO:CJNE R0,#01H,YIWEI;判断输入了几个数，是否移位MOV 30H,34HMOV 50H,37HMOV 40H,#00HAJMP BACK1YIWEI:CJNE R1,#01H,ERWEIMOV 31H,30HMOV 30H,34HMOV 51H,50HMOV 50H,37HMOV 41H,#00HAJMP BACK1ERWEI:CJNE R2,#01H,BACK1MOV 32H,31HMOV 31H,30HMOV 30H,34HMOV 52H,51HMOV 51H,50HMOV 50H,37HMOV 42H,#00HBACK1: MOV 35H,#00HCLR CMOV A,38HCJNE A,00H,BQLMOV A,34HCJNE A,#77H,BQL;判断是否 为10（清零）LJMP CHUSHIBQL:ACALL DAYLJMP TESTDENG:MOV A,P3;子程序 三个数码管轮流发光CJNE A,#04H,BIAN1;P3 口001 010 100轮流变换RR AMOV P3,AAJMP HUIBIAN1:CJNE A,#02H,BIAN2RR AMOV P3,AAJMP HUIBIAN2:MOV P3,#04HHUI:MOV R5,P3CJNE R5,#01H,FIRMOV P1,30H AJMP BACKFIR:CJNE R5,#02H,SECMOV P1,31HAJMP BACKSEC:MOV P1,32H BACK:MOV TH1,#0DFHMOV TL1,#0FFHRETIJISHI:DJNZ R4,RET0;子程序 倒计时MOV R4,#0AH;10次后，开始减数计时MOV R0,50HMOV R1,51HMOV R2,52HCJNE R0,#00H,GEWEI;判断是否开始借位CJNE R1,#00H,SHIWEI;三位轮流判断CJNE R2,#00H,BAIWEI;如果倒计时为0，则结束计时，一切归零CLR TR0CLR ET0MOV 30H,#3FHMOV 31H,#3FHMOV 32H,#3FHMOV 34H,#00HMOV 35H,#00HMOV 37H,#00HMOV 38H,#00HMOV 40H,#01H MOV 41H,#01H MOV 42H,#01H MOV 50H,#00HMOV 51H,#00HMOV 52H,#00HAJMP RET0GEWEI:DEC R0MOV 50H,R0MOV A,50HMOV DPTR,#TAB2MOVC A,A+DPTRMOV 30H,AAJMP RET0SHIWEI:MOV 50H,#09HMOV 30H,#6FHDEC R1MOV 51H,R1MOV A,51HMOV DPTR,#TAB2MOVC A,A+DPTRMOV 31H,AAJMP RET0BAIWEI:MOV 50H,#09HMOV 30H,#6FHMOV 51H,#09HMOV 31H,#6FHDEC R2MOV 52H,R2MOV A,52HMOV DPTR,#TAB2MOVC A,A+DPTRMOV 32H,ARET0:MOV TH0,#3CHMOV TL0,#0B0HSETB TR0RETITAB1:DB 0EEH,0DEH,0BEH,7EH,0EDH,0DDH,0BDH,7DH,0EBH,0DB