51单片机延时0.5s和20ms的程序(汇编) 12M晶振答:LCALL DELAY_20MS ;包括lcall和返回一共20ms,误差0us DELAY_20MS: ;60H,61H,62H MOV 62H,#26 MOV 61H,#5 MOV 60H,#74 DJNZ 60H,NOP DJNZ 61H,$-7 DJNZ 62H,$-13 RET ;--- LCALL DELAY_500MS ;包括lcall和返回一共0.5s,误差0us DELAY_500MS: ;60H,61H,62...
51单片机汇编语言写串口程序答:ORG 0000H SJMP 0050H ORG 0023H LJMP S_INT TAB:DB 20H,49H,20H,47H,45H,54H,20H,'NULL'ORG 0050H MOV TMOD,#20H MOV TH1,#0FDH MOV TL1,#0FDH SETB TR1 SETB SM1 CLR SM0 SETB EA SETB ES MOV R0,#30H MOV A,#1H MAIN:SETB REN ACALL DELAY JNZ MAIN MOV R2,#0 MOV ...