进行中断链分配

时间:2011-02-24 23:41:48

标签: c assembly interrupt interrupt-handling

正如标题所说,我正试图进行中间链接。我正在寻找的是当调用定时器中断(IRQ 0),并且中断处理程序(ISR)完成时,它执行我的代码。我试图用Assembly,C或任何允许我这样做的语言来做。我在这个page上找到了一个例子,但它不适用于TASM。你可以帮我解决这个问题,或者我可以在哪里找到相关信息吗?谢谢。 :d

1 个答案:

答案 0 :(得分:3)

我不再使用它了,但是我想再次使用汇编程序,我已经完成了汇编的第一步:

.186
.MODEL TINY, C

.code
ORG 100h

Entry:
; Install handler
   push   ds
   xor    cx, cx
   mov    ds, cx
   mov    ax, ds:[8*4]
   mov    dx, ds:[8*4+2]
   cli
   mov    ds:[8*4], OFFSET InterruptHandler
   mov    ds:[8*4+2], cs
   pop    ds
   mov    word ptr [OldIntVect], ax
   mov    word ptr [OldIntVect+2], dx
   sti

; Wait for the user to press a key. In the meantime you should see lots of wildcards!
   xor   ax, ax
   int   16h

; Restore original handler
   mov    ax, word ptr [OldIntVect]
   mov    dx, word ptr [OldIntVect+2]
   push   ds
   xor    cx, cx
   mov    ds, cx
   cli
   mov    ds:[8*4], ax
   mov    ds:[8*4+2], dx
   sti
   pop    ds

; Exit to DOS
   int   20h

PROC MyHandler

   mov   ah, 0Eh
   mov   al, '*'
   int   10h
   ret
ENDP


InterruptHandler:
   pushf
   call  cs:[OldIntVect]
   cmp   [busy], 0
   jne   ExitHandler ; If jumps then the timer was faster than the time it takes for MyHandler to complete

   mov   cs:[busy], 1
   pusha
   call  MyHandler ; Other options are using a pointer to function or just inlining the code here.
   popa
   mov   cs:[busy], 0

ExitHandler:
   iret

OldIntVect dd ?
busy       db ?

END Entry

在WinXP(32位)下测试:

>tasm timer.asm
Turbo Assembler  Version 1.01  Copyright (c) 1988, 1989 Borland International

Assembling file:   TIMER.ASM
Error messages:    None
Warning messages:  None
Remaining memory:  481k


>tlink /t timer.obj
Turbo Link  Version 3.0 Copyright (c) 1987, 1990 Borland International

>timer
***************************

但是这当然只对DOS环境(DOSBox,Windows 32位版本等)有效,并且最多只能对引导加载程序进行一些调整。

无论如何,感谢你给我恢复这一切的美好时光:P