【标题】：汇编实时显示系统时间年月日信息
【关键字】：
【来源】：http://blog.csdn.net/pfboy/archive/2007/04/03/1550430.aspx

汇编实时显示系统时间年月日信息

编写一个程序，在屏幕上实时地显示日期和时间（例如：2007-4-12 15：32：58显示为3：32：20 P.M. Saturday,April 12,2007）直到任意一个键被按下才退出程序。

showyear macro char
push ax
push si
push cx
push dx
push bx
push di
        mov     ax,char
        mov     si, offset divisors
        mov     di, offset results
        mov     cx,5
aa:
        mov     dx,0
        div     word ptr [si]   ;除法指令的被除数是隐含操作数，此处为dx:ax，商ax,余数dx
        add     al,48           ;商加上48即可得到相应数字的ASCII码
        mov     byte ptr [di],al
        inc     di
        add     si,2
        mov     ax,dx
        loop    aa
        mov     cx,4
        mov     di, offset results
bb:
        cmp     byte ptr [di],'0'   ;不输出前面的0字符
        jne     print
        inc     di
        loop    bb
print:
        mov     dx,di
        mov     ah,9
        int     21h

        pop di
        pop bx
        pop dx
        pop cx
        pop si
        pop ax
endm

DISP MACRO CHAR ;显示字符
PUSH AX
PUSH DX

MOV DL,CHAR
MOV AH,2
INT 21H

POP DX
POP AX
ENDM

GETNUM MACRO CHAR ;显示数字
PUSH AX
PUSH DX
PUSH CX
MOV AL,CHAR
AAM
MOV DH,AL
MOV DL,AH
OR DL,30H
MOV AH,2
INT 21H

MOV DL,DH
OR DL,30H

MOV AH,2
INT 21H
POP CX
POP DX
POP AX
ENDM

GETWEEK MACRO CHAR ;显示星期
PUSH AX
PUSH DX
PUSH SI
PUSH CX

LEA SI,D_TAB

MOV AL,CHAR
XOR AH,AH
MOV CX,AX
LOOP1:INC SI
    INC SI
  LOOP LOOP1

MOV DX,[SI]
MOV AH,9
INT 21H

POP CX
POP SI
POP DX
POP AX
ENDM

GETMONTH MACRO CHAR ;显示月份
PUSH AX
PUSH DX
PUSH SI
PUSH CX

LEA SI,M_TAB

MOV AL,CHAR
DEC AL
XOR AH,AH
MOV CX,AX

LOOP2:INC SI
    INC SI
  LOOP LOOP2

MOV DX,[SI]
MOV AH,9
INT 21H

POP CX
POP SI
POP DX
POP AX
ENDM

DATAS SEGMENT
divisors DW 10000, 1000, 100, 10, 1
results DB 0,0,0,0,0,"$" ;存放五位数ASCII码
BUF DB 'A$'
BUF1 DB 'YUE$'

D_TAB DW SUN,MON,TUE,WED,THU,FRI,SAT
M_TAB DW JAN,FEB,MAR,APR,MAY,JUN,JUL,AUG,SEP,OCT,NOV,DCE,TIM

SUN DB 'Sunday$'
MON DB 'Monday$'
TUE DB 'Tuesday$'
WED DB 'Wednesday$'
THU DB 'Thursday$'
FRI DB 'Friday$'
SAT DB 'Saturday$'

JAN DB 'January$'
FEB DB 'February$'
MAR DB 'March$'
APR DB 'April$'
MAY DB 'May$'
JUN DB 'June$'
JUL DB 'July$'
AUG DB 'August$'
SEP DB 'September$'
OCT DB 'October$'
NOV DB 'November$'
DCE DB 'December$'
TIM DB '.M. $'

DATAS ENDS

STACKS SEGMENT
;此处输入堆栈段代码
STACKS ENDS

CODES SEGMENT
    ASSUME CS:CODES,DS:DATAS,SS:STACKS
START:
    MOV AX,DATAS
    MOV DS,AX

LLL:
mov ah,2
mov bh,0
mov dh,0
mov dl,0
int 10h

MOV AH,2CH
INT 21H
GETNUM CH
DISP 3AH
GETNUM CL
DISP 3AH
GETNUM DH
DISP 00H
CMP CH,12
JA P
DISP 41H
JMP A
P: DISP 50H
A: MOV DX,M_TAB+24
MOV AH,9
INT 21H

MOV AH,2AH
INT 21H