With Windows 1ch, users can interrupt their own clock and Run DOS programs normally.

Program purpose: use Windows 1ch to provide users with the ability to interrupt their own clock and Run DOS programs normally *

Program Author: Wang dingqiao, class 0801, Computer Science and Technology College, Hubei Normal University *
Core algorithms: extract and save the original interruption, create a new middle-segment read time, and resident the memory, and then exit and execute the original and new middle-segment display time in sequence to return the Middle-segment *
; Production time *
; Program copyright: the code is publicly available for learning and communication, but cannot be referenced in all. To use it, Please carefully understand it before making it by yourself *
Additional instructions: This program is an experiment in the operating system experiment *
Main reference: IBM-PC assembly language programming Huaihai Institute of Technology Liu jingliang microcomputer principle and interface technology system residence time Design **
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Codesg segment; the program only describes assume DS: codesg, CS: codesgmain proc far start: push ds sub ax, ax push ax mov ax, codesg mov ds, ax; ------------------------------- take the original interrupt vector of 1ch and save mov Al, 1ch mov ah, 35 h int 21 h mov oldint, BX mov BX, es mov oldint + 2, BX; ------------------------------- reset 1ch interrupt vector mov dx, offset updtime mov ax, SEG updtime mov ds, ax mov Al, 1ch mov ah, 25 h int 21 h ;--------------------------------- Take the current time and save mov ah, 2ch int 21 h mov hour, CH mov min, CL mov sec, DH; --------------------------------- the program resident memory and exit mov ah, 31 H mov Al, 0 mov dx, (prog_len + 15)/16) + 16; calculates the resident byte int 21 h main endp; ---------------------------------------------------- the new part of updtime proc near; --------------------------------- first execute the original interrupted content pushf call dword ptr Cs: oldint; ------------------------------- start executing the newly added content push ax ;---------- Protection Register push BX push CX push DX; ----------------------------------- use the DS register to specify the address of the stored data mov ax, codesg mov ds, ax; --------------------------------- display of processing time and count jnz exit of the incoming part; do not include carry in the second before the time, continue to interrupt add sec, 1; ---------- processing second CMP sec, 60 jnz docnt; if the period does not reach one minute, no carry is required. mov sec, 0 add min, 1; ---------- CMP min, 60 jnz docnt are interrupted. If the period does not reach one hour, no carry is required. mov Min is interrupted, 0 add hour, 1; ---------- CMP hour, 24 jnz docnt during processing; do not carry until 24, continue Interrupt mov hour, 0 docnt: mov count, 18; reset the counter call timeshow when the time reaches one second; update the time only when the 1 second arrives, and do not update exit when the time is not reached :; -------------------------- return interrupted pop DX; ---------- recovery register pop CX pop BX pop ax iretupdtime endp; effectimeshow proc near; --------------- display on the screen based on time; cursor reads the current cursor position and stores xor bh, BH mov ah, 03 h int 10 h mov cur, DX ;------------------------------- -- Set the cursor to the appropriate position xor bh, BH mov DH, 0 mov DL, 71 mov ah, 02 int 10 h; --------------------------------- display hour sub BX, BX mov BL, hour call bindec; call two-digit decimal digit display subroutine call semi; call semicolon display subroutine; ------------------------------- minute sub BX, BX mov BL, Min call bindec call semi; ------------------------------- display Second sub BX, BX mov BL, SEC call bindec; --------------------------------- restore cursor xor bh, BH mov dx, cur mov ah, 02 h int 10 h re T timeshow endp; then display the two-digit decimal number bindec proc near mov CX, 10 call dec_div; calculate 10 calls curmove mov CX, 1 call dec_div before converting the two-digit decimal number; call curmove retbindec endp when converting a two-digit decimal number, and convert the two-digit decimal number to the one-digit decimal number to display dec_div proc near mov ax, BX mov dx, 0 Div CX; divide mov BX according to the content in CX, DX push BX add Al, 30 h; display the sizes of suppliers xor bh, BH MoV BL, 41 h mov ah, 09 h mov CX, 1 int 10 h pop BX; retain the remainder so that a single digit retdec_div endp can be calculated next time; returns the semicolon semi proc near mov Al, ':' xor bh, BH mov BL, 41 h mov ah, 09 h mov CX, 1 int 10 h call curmove RET semi endp; ------------------------------------------------------ move the cursor curmove proc near mov ah, 03 int 10 h Inc DL mov ah, 02 int 10 h retcurmove endp ;------------ ------------------------------------------ The data to be saved and used; ------------ save the old vector oldint DW 2 DUP (?); ------------ Timing parameter count DW 18 hour db 0 min db 0 sec db 0; ------------ cursor parameter cur DW 0; ---------------- prog_len equ $-Main codesg endsend start

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Running effect:

The corresponding program: http://download.csdn.net/detail/ziyuanxiazai123/2791641