汇编语言-读取系统日期和时间

DATA SEGMENT
YEAR DW ?
MONTH DB ?
DAY DB ?
WEEK DB ?
HOUR DB ?
MINUTE DB ?
SECOND DB ?
DATE DB 10 DUP(?),'$'
TIME DB 10 DUP(?),'$'
DAYNUM DB 10 DUP(?),'$'
DATESTR DB 'The date is $'
WEEKSTR DB 'Today is $'
TIMESTR DB 'The time is $'
DAYSTR DB 'Today on the whole year is $'
WEEKDAY DB 'MONTUSWEDTHUFRISATSUN$'
MONTHEN DB 'JUNFEBMARAPRMAYJUEJULAUGSEPOCTNOVDEC$'
DAYS DB 31,28,31,30,31,30,31,31,30,31,30,31,'$'
DAYS1 DB 31,29,31,30,31,30,31,31,30,31,30,31,'$'
DATA ENDS
STACK SEGMENT STACK
DB 200 DUP(0)
STACK ENDS
CODE SEGMENT
ASSUME CS:CODE,DS:DATA,SS:STACK
START:MOV AX,DATA
      MOV DS,AX
      ;///调用DOS 2AH功能。获取系统当前日期。
      MOV AH,2AH
      INT 21H

      MOV YEAR,CX;年（1980-2099）
      MOV MONTH,DH;月(1-12)
      MOV DAY,DL;日(1-31)
      MOV WEEK,AL;星期(0-6)0表示星期一,6表示星期天.
      LEA DX,DATESTR
      MOV AH,9
      INT 21H
      ;////输出月份
      MOV BX,OFFSET MONTHEN
      MOV AL,[MONTH];不能写成MOV AL，MONTH-1或者MOV AL，[MONTH]-1
      DEC AL
      MOV CL,3
      MUL CL
      MOV SI,AX;将偏移地址3*(month-1)赋值给SI
      MOV AH,2
      MOV DL,[BX+SI]
      INT 21H
      MOV DL,[BX+SI+1]
      INT 21H
      MOV DL,[BX+SI+2]
      INT 21H
      ;///输出空格
      MOV AH,2
      MOV DL,0
      INT 21H
      MOV DL,0
      INT 21H
      ;///输出该月的第几天
      MOV AL,DAY
      MOV AH,0