From:	"Alvin Lau" <alvin_lau AT yahoo DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Inline assembly code problem
Date:	Sat, 17 Jun 2000 15:36:43 +0800
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

When I run the following code, my computer will halt and sometimes will
reboot automatically:

int main(void)
{
  unsigned factor=4;
  unsigned short rate=1193180/(18*factor);
  // speed up timer
  asm (
    "cli\n"
    "movb $36h,%%al\n"
    "outb %%al,$43h\n"
    "movw %0,%%ax\n"
    "outb %%al,$40h\n"
    "movb %%ah,%%al\n"
    "outb %%al,$40h\n"
    "sti\n"
    :
    :"m"(rate)
  );
}

Anyone can tell me why ?
I saw same code appearing in some timer modules.

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