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    SubjectRe: ioport conflict with "dma page reg" (0x80)
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    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.

    Roger.

    --
    ** R.E.Wolff@BitWizard.nl ** http://www.BitWizard.nl/ ** +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

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