nczl.asm

汇编dos下时间的内存驻留源程序16位汇编下完成

.386
STACK SEGMENT USE16 STACK
      DB 200 DUP(0)
STACK ENDS
CODE SEGMENT USE16 
     ASSUME CS:CODE,DS:CODE,SS:STACK
     COUNT DB 18
     HOUR DB ?,?,':'
     MIN  DB ?,?,':'
     SEC  DB ?,?,':'
     BUF_LEN =$-HOUR
     CURSOR DW ?
     OLD_INT DW ?,?

NEW08H PROC FAR
       PUSHF
       CALL DWORD PTR CS: OLD_INT
       DEC CS:COUNT
       JZ  DIZP
       IRET
DISP:  MOV CS:COUNT ,18
       STI
       PUSHA
       PUSH DS
       PUSH ES
       MOV AX,CS
       MOV DS,AX
       MOV ES,AX
       CALL GET_TIME
       MOV BH,0
       MOV AH,3
       INT 10H
       MOV CURSOR,DX
       MOV BP,OFFSET HOUR
       MOV BH,0
       MOV BH,0
       MOV DL,80-BUF_LEN
       MOV BL,07H
       MOV CX,BUF_LEN
       MOV AL,0
       MOV AH,13H
       INT 10H
       MOV BH,0
       MOV DX,CURSOR
       MOV AH,2H
       INT 10H
       POP ES
       POP DS
       POPA
       IRET
NEW08H ENDP

GET_TIME PROC
         MOV AL,4H
         OUT 70H,AL
         JMP $+2
         IN  AL,71H
         MOV AH,AL
         AND AL,0FH
         SHR AH,4
         ADD AX,3030H
         XCHG AH,AL
         MOV  WORD PTR HOUR,AX
         MOV AL,2
         OUT 70H,AL
         JMP $+2
         IN AL,71H
         MOV AH,AL
         AND AL,0FH
         SHR AH,4
         ADD AX,3030H
         XCHG AH,AL
         MOV WORD PTR MIN,AX
         MOV AL,0
         OUT 70H,AL
         JMP $+2
         IN  AL,71H
         MOV AH,AL
         AND AL,0FH
         SHR AH,4
         ADD AX.3030H
         XCHG AH,AL
         MOV WORD PTR SEC,AX
         RET
GET_TIME ENDP


BEGIN:   PUSH CS
         POP  DS
         MOV AX,3508H
         INT 21H
    
         MOV OLD_INT,BX
         MOV OLD_INT+2,ES
         MOV DX,OFFSET NEW08H
         MOV AX,2508H
         INT 21H


NEXT:   MOV AH,0
        INT  16H
        CMP  AL,'q'
        JNE  NEXT
        LDS  DX,DWORD PTR OLD_INT
        
        MOV AX,2508H
        INT 21H
        MOV AH,4CH
        INT 21H
CODE    ENDS
        END BEGIN