DOS下TSR程序的汇编演示代码介绍

我喜欢在DOS下用QE.EXE来阅读文本文件,自已按键手痛。于是写了个自动向键盘缓冲区放UP
和DOWN键值的程序。
; <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
; 文件名: AutoKey.asm
; 功 能: 自动向键盘缓冲区填充RIGHT 或 DOWN 键值 来移动光标
; Ctrl + Tab 停止填充
; Ctrl + → 填充RIGHT 键值
; Ctrl + ↓ 填充DOWN 键值
; Ctrl + ↑ 提高填充速度
; Ctrl + ← 降低填充速度
;
; 作 者: 黄志斌 2003年2月 广西河池
;
; 申 明: 可以自由转载,应保存完整性.且不能用于商业用途
;
; 说 明:
; 1. 第一次运行时常驻内存,再次运行则撤出内存
; 2. 适用于QE.EXE 和 TC.EXE, 不适于 EDIT.COM
; 3. 改进方向:
; A 在屏幕右上角显示当前速度
; B 填充RIGHT 键值时能自动换行
; 开发环境: IBM PC 486, MSDOS7.0(mswin95), MASM生成
; Log
; -----------------------------------------------------------------------
; 2003.02.24 Created, but the result is exception!
; 2003.02.25 
OK!<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

cseg segment
;==============================
 org 100h
 assume es: cseg, ss: cseg
 assume cs: cseg, ds: cseg

UP EQU 48h
Left EQU 4bh
RIGHT EQU 4dh
DOWN EQU 50h

Ctrl EQU 04h
Alt EQU 08h
EndKey EQU 4fh
Tab EQU 0Fh
AddKey EQU 0dh
DecKey EQU 0ch

RightDelay equ 10
DownDelay equ 100

;-----------------------------
start: jmp @Init
 ;====================
 Old1cAddr label dword
 Old1cOff dw ?
 Old1cSeg dw ?
 Old09Addr label dword
 Old09Off dw ?
 Old09Seg dw ?
 mcb_evb dw ? ; mcb: Memmory Control Block
 mcb_psp dw ?
 show dw 1
 count dw 0
 FillKey db 0
 time dw 0
 AutoKey label word
 db 00
 KeyCode db RIGHT

 VarLen equ $ - Old1cAddr

;---------------
new09h proc far
 sti
 push ax
 push bx
 push ds

 mov ax, 0040h
 mov ds, ax
 mov bh, ds:[017h]
 push cs
 pop ds
 test bh, Ctrl
 jz @old09
 in al, 60h
 cmp al, Tab ;EndKey
 jne @right
 mov FillKey, 0
 mov KeyCode, 0
 jmp @Old09
@right:
 cmp al, RIGHT
 jnz @down
 mov byte ptr KeyCode, RIGHT
 mov time, RightDelay
 jmp @AutoON
@down:
 cmp al, DOWN
 jnz @up
 mov byte ptr KeyCode, DOWN
 mov time, DownDelay
 jmp @AutoON
@up:
 cmp al, UP
 jnz @left
 cmp word ptr time, 1
 je @Old09
 dec time
 jmp @ClrCount ;jmp @Old09
@left:
 cmp al, LEFT
 jnz @Old09
 cmp word ptr time, 0ffffh
 je @Old09
 inc time
 ;jmp @ClrCount
@AutoON:
 mov FillKey, 1
@ClrCount:
 mov count, 0
@Old09:
 pop ds
 pop bx
 pop ax
 jmp cs:Old09Addr
new09h endp

new1ch proc far
 cmp byte ptr cs:FillKey, 1
 jne @Old1c

 push ds

 push cs
 pop ds
 inc count
 mov ax, time
 cmp ax, count
 jne n1c

 mov count, 0
 push ax
 push bx

 mov ax, 0040h
 mov ds, ax
 cli

 mov bx, word ptr ds:[001ch]
 mov ax, cs: AutoKey
 mov [bx], ax
 inc bx
 inc bx

 cmp bx, 003eh
 jnz @NoTail
 mov bx, 001eh
@NoTail:
 mov ax, bx
 mov bx, 001ch
 mov [bx], ax

 sti
 pop bx
 pop ax
n1c:
 pop ds
@Old1c:
 jmp cs:Old1cAddr
new1ch endp

@Init:
 mov ax, 3509h ; Get current 1ch interrupt vector
 int 21h

 cmp bx, offset new09h ; Has been Intalled?
 jnz @install ; No install

 mov dx, offset strMsgUninstall
 mov ah, 09h
 int 21h

 mov bx, 1ch * 04h ; Restore old 1ch interrupt vector
 xor ax, ax ; to System interrupt vector talbe
 mov ds, ax
 mov ax, es:[Old1cOff]
 mov ds:[bx], ax
 mov ax, es:[Old1cSeg]
 mov ds:[bx+2], ax

 mov bx, 09h * 04h ; Restore old 09h interrupt vector
 mov ax, es:[Old09Off] ; to System interrupt vector talbe
 ;xor ax, ax 
 ;mov ds, ax ; ds must equal 0
 mov ds:[bx], ax 
 mov ax, es:[Old09Seg]
 mov ds:[bx+2], ax

 mov bx, 1 ; Release evirenment parameter block
 mov ax, es:[mcb_evb]
 mov ds, ax
 mov word ptr ds:[bx], 0

 mov ax, es:[mcb_psp] ; Release TSR
 mov ds, ax
 mov word ptr ds:[bx], 0
 mov ax, 4c00h
 int 21h

@install:
 ;mov ax, 3509h ; Get current 1ch interrupt vector
 ;int 21h
 mov Old09Seg, es ; Store current 09h interrupt vector
 mov Old09Off, bx

 mov dx, offset new09h ; Set new 09h interrupt vector
 mov ax, 2509h
 int 21h

 mov ax, 351ch ; Get current 1ch interrupt vector
 int 21h
 mov Old1cSeg, es ; Store current 1ch interrupt vector
 mov Old1cOff, bx

 mov dx, offset new1ch ; Set new 1ch interrupt vector
 mov ax, 251ch
 int 21h

 mov dx, offset strMsgInstall
 mov ah, 09h
 int 21h

 ; Store the address of evirenment parameter block
 mov ax, cs
 dec ax
 mov [mcb_psp], ax ;mov cs:[mcb_psp], ax
 mov bx, 2ch
 mov ax, [bx] ;mov ax, cs:[bx]
 dec ax
 mov cs:[mcb_evb], ax

 mov dx, offset @Init
 add dx, VarLen + 2
 mov cl, 04h
 shr dx, cl
 mov ax, 3100h
 int 21h
 ;====================
 strMsgInstall db 07h, "AutoKey installed!$"
 strMsgUninstall db 07h, "AutoKey uninstalled!$"
cseg ends
 end start