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Based on kernel version 3.15.4. Page generated on 2014-07-07 09:05 EST.

1	Last reviewed: 10/05/2007
2	
3	                     Berkshire Products PC Watchdog Card
4	                   Support for ISA Cards  Revision A and C
5	           Documentation and Driver by Ken Hollis <kenji@bitgate.com>
6	
7	 The PC Watchdog is a card that offers the same type of functionality that
8	 the WDT card does, only it doesn't require an IRQ to run.  Furthermore,
9	 the Revision C card allows you to monitor any IO Port to automatically
10	 trigger the card into being reset.  This way you can make the card
11	 monitor hard drive status, or anything else you need.
12	
13	 The Watchdog Driver has one basic role: to talk to the card and send
14	 signals to it so it doesn't reset your computer ... at least during
15	 normal operation.
16	
17	 The Watchdog Driver will automatically find your watchdog card, and will
18	 attach a running driver for use with that card.  After the watchdog
19	 drivers have initialized, you can then talk to the card using a PC
20	 Watchdog program.
21	
22	 I suggest putting a "watchdog -d" before the beginning of an fsck, and
23	 a "watchdog -e -t 1" immediately after the end of an fsck.  (Remember
24	 to run the program with an "&" to run it in the background!)
25	
26	 If you want to write a program to be compatible with the PC Watchdog
27	 driver, simply use of modify the watchdog test program:
28	 Documentation/watchdog/src/watchdog-test.c
29	
30	
31	 Other IOCTL functions include:
32	
33		WDIOC_GETSUPPORT
34			This returns the support of the card itself.  This
35			returns in structure "PCWDS" which returns:
36				options = WDIOS_TEMPPANIC
37					  (This card supports temperature)
38				firmware_version = xxxx
39					  (Firmware version of the card)
40	
41		WDIOC_GETSTATUS
42			This returns the status of the card, with the bits of
43			WDIOF_* bitwise-anded into the value.  (The comments
44			are in linux/pcwd.h)
45	
46		WDIOC_GETBOOTSTATUS
47			This returns the status of the card that was reported
48			at bootup.
49	
50		WDIOC_GETTEMP
51			This returns the temperature of the card.  (You can also
52			read /dev/watchdog, which gives a temperature update
53			every second.)
54	
55		WDIOC_SETOPTIONS
56			This lets you set the options of the card.  You can either
57			enable or disable the card this way.
58	
59		WDIOC_KEEPALIVE
60			This pings the card to tell it not to reset your computer.
61	
62	 And that's all she wrote!
63	
64	 -- Ken Hollis
65	    (kenji@bitgate.com)
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