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67 lines
2.2 KiB
Plaintext
67 lines
2.2 KiB
Plaintext
Last reviewed: 10/05/2007
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Berkshire Products PC Watchdog Card
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Support for ISA Cards Revision A and C
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Documentation and Driver by Ken Hollis <kenji@bitgate.com>
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The PC Watchdog is a card that offers the same type of functionality that
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the WDT card does, only it doesn't require an IRQ to run. Furthermore,
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the Revision C card allows you to monitor any IO Port to automatically
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trigger the card into being reset. This way you can make the card
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monitor hard drive status, or anything else you need.
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The Watchdog Driver has one basic role: to talk to the card and send
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signals to it so it doesn't reset your computer ... at least during
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normal operation.
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The Watchdog Driver will automatically find your watchdog card, and will
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attach a running driver for use with that card. After the watchdog
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drivers have initialized, you can then talk to the card using a PC
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Watchdog program.
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I suggest putting a "watchdog -d" before the beginning of an fsck, and
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a "watchdog -e -t 1" immediately after the end of an fsck. (Remember
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to run the program with an "&" to run it in the background!)
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If you want to write a program to be compatible with the PC Watchdog
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driver, simply use of modify the watchdog test program:
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Documentation/watchdog/src/watchdog-test.c
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Other IOCTL functions include:
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WDIOC_GETSUPPORT
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This returns the support of the card itself. This
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returns in structure "PCWDS" which returns:
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options = WDIOS_TEMPPANIC
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(This card supports temperature)
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firmware_version = xxxx
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(Firmware version of the card)
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WDIOC_GETSTATUS
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This returns the status of the card, with the bits of
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WDIOF_* bitwise-anded into the value. (The comments
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are in linux/pcwd.h)
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WDIOC_GETBOOTSTATUS
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This returns the status of the card that was reported
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at bootup.
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WDIOC_GETTEMP
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This returns the temperature of the card. (You can also
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read /dev/watchdog, which gives a temperature update
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every second.)
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WDIOC_SETOPTIONS
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This lets you set the options of the card. You can either
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enable or disable the card this way.
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WDIOC_KEEPALIVE
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This pings the card to tell it not to reset your computer.
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And that's all she wrote!
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-- Ken Hollis
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(kenji@bitgate.com)
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