ＦＹＩ
在预定时间内无响应，则启动预置功能（关机、报警、上锁等等）

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Note added at 29 mins (2007-02-02 05:35:24 GMT)
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例：
Deadman Timer資訊出現在資訊欄，必須按Deadman Timer按鈕予以確認，若未能在指定時間內確認此資訊，會進入報警狀態，用戶會被登出。

http://www.hitrontech.com/solution/solution.asp?contenttypei...

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Note added at 32 mins (2007-02-02 05:37:56 GMT)
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再例：
Line 43 is the deadman timer. If we don't make it up here at least every $TIMEOUT seconds, we're dead.
http://www.stonehenge.com/merlyn/WebTechniques/col56.html



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Note added at 35 mins (2007-02-02 05:41:18 GMT)
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继续例：
a deadman timer means, responsive to the reset signals, for generating an interrupt signal whenever a reset signal is not generated within the predetermined maximum time period for the reset signal, the generation of the interrupt signal being indicative of the processing means operating in an undetermined mode, and wherein the processing means being responsive to the interrupt signal begins operating in a predetermined mode prior to generating the first and second controller control signal.

http://www.wikipatents.com/4749991.html

嗯……应该够了！

http://www.rtems.org/onlinedocs/releases/4.5.0/rtemsdoc-4.5....

8.2.2 Timers

A timer is an RTEMS object which allows the application to schedule operations to occur at specifc times in the future. User supplied timer service routines are invoked by the
rtems.clock_tick directive when the timer fires. Timer service routines may perform any operations or directives which normally would be performed by the application code which invoked the rtems.clock_tick directive.

The timer can be used to implement watchdog routines which only fire to denote that an application error has occurred. The timer is reset at specific points in the application to insure that the watchdog does not fire. Thus, if the application does not reset the watchdog timer, then the timer service routine will fire to indicate that the application has failed to reach a reset point. This use of a timer is sometimes referred to as a "keep alive" or a
"deadman" timer.

自动关闭定时器

指在没相应，或者错误用户登陆的情况下，用于自动关闭的定时器。

If the Deadman Timer is enabled the P2140 will automatically shut itself down after a user selectable time (normally 72 hours) if the unit remains in Standby/Sleep too long. Mac mini users will appreciate the Deadman Timer since most Macs require Sleep mode instead of hibernate.
http://www.carnetix.com/P2140/CNXP2140.htm