SHOW MACRO C ;宏定义字符串显示输出
MOV AH,09H
LEA DX,C
INT 21H
ENDM
;---------------------------------------------------
DATA SEGMENT ;数据段
TIME DB '23:59:56$' ;定义时分秒
DATA ENDS
;---------------------------------------------------
STACK SEGMENT ;堆栈段
STA DB 128 DUP(?)
TOP EQU LENGTH STA
STACK ENDS
;---------------------------------------------------
CODE SEGMENT ;代码段
ASSUME CS:CODE,DS:DATA,SS:STACK
START: MOV AX,DATA
MOV DS,AX
MOV AX,STACK
MOV SS,AX
MOV AX,TOP
MOV SP,AX ;初始化
MOV SI,OFFSET TIME
Q0: CALL LOCATION
SHOW TIME ;显示时间
CALL TIMER ;时间延迟1秒
MOV SI,OFFSET TIME ;恢复SI
CMP BYTE PTR [SI+7],39H
JB Q1
MOV BYTE PTR [SI+7],30H
CMP BYTE PTR [SI+6],35H
JB Q2
MOV BYTE PTR [SI+6],30H
CMP BYTE PTR [SI+4],39H
JB Q3
MOV BYTE PTR [SI+4],30H
CMP BYTE PTR [SI+3],35H
JB Q4
MOV BYTE PTR [SI+3],30H
CMP BYTE PTR [SI+1],33H
JB Q5
MOV BYTE PTR [SI+1],30H
CMP BYTE PTR [SI],32H
JB Q6
MOV BYTE PTR [SI],30H
JMP Q0
Q1: ADD BYTE PTR [SI+7],01H
JMP Q0
Q2: ADD BYTE PTR [SI+6],01H
JMP Q0
Q3: ADD BYTE PTR [SI+4],01H
JMP Q0
Q4: ADD BYTE PTR [SI+3],01H
JMP Q0
Q5: ADD BYTE PTR [SI+1],01H
JMP Q0
Q6: ADD BYTE PTR [SI],01H
JMP Q0
MOV AX,4C00H ;返回DOS
INT 21H
;---------------------------------------------------
TIMER PROC NEAR ;延时函数(延时1秒)
PUSH CX ;保存原先的CX
MOV CX,57343
T1: PUSH CX
MOV CX,6
T2: NOP ;空指令
MOV AH,01H ;读取键盘状态
INT 16H
JNZ T3
LOOP T2 ;延时
POP CX ;提取原先的CX
LOOP T1 ;循环57343次
POP CX
RET
T3: MOV AX,4C00H
INT 21H
TIMER ENDP
;---------------------------------------------------
LOCATION PROC NEAR ;设置光标位置
MOV DL,36
MOV DH,12
MOV BH,0
MOV AH,02H
INT 10H
RET
LOCATION ENDP
;---------------------------------------------------
CODE ENDS
END START
