[lkml]   [1999]   [Mar]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: ioport conflict with "dma page reg" (0x80)
Richard B. Johnson wrote:
> On Mon, 15 Mar 1999, Wall, Tim wrote:
> > I have a single-board computer with a hardware watchdog which uses I/O
> > addresses 0x80, 0x443, and 0x444.
> >
> > The problem is that something else in the system is writing to 0x80,
> > which resets/disables the watchdog.
> >
> 0x80 is the manufacturing test port. If you have a watchdog that
> cares about that, it's broken. The kernel didn't reserve it, the
> AT-Class hardware did. In fact during POST, you can read numbers
> written to that port to see how far a, possibly defective, board
> has gotten upon power up.

But, using port 0x80 to keep the watchdog from activating is a good
way of making sure that the system comes through the POST before the
watchdog kicks in....

Read Alans reply for the hint on how to get along.


** ** ** +31-15-2137555 **
*-- BitWizard writes Linux device drivers for any device you may have! --*
* Never blow in a cat's ear because if you do, usually after three or *
* four times, they will bite your lips! And they don't let go for at *
* least a minute. -- Lisa Coburn, age 9

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:50    [W:0.053 / U:1.420 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site