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Owning Palette: Real-Time Watchdog VIs

Installed With: RT Module

Configures a new watchdog object with a timeout and expiration actions.

Details  Example

	timeout is the timeout period for the watchdog timer specified in seconds. The timeout period specifies the amount of time that must elapse before the watchdog timer expires. The timeout period is coerced to a value determined from the available timebase and initial count values. The default is 1 second.
	expiration actions specifies which actions to take when the watchdog timer expires. You can use any combination of actions. However, not all targets support all actions. Refer to the specific RT target hardware documentation for information about supported actions. reset reboots the PXI controller. occurrence sets the occurrence when the watchdog timer expires. trigger line is the trigger line on the PXI bus to be asserted when the watchdog timer expires. Refer to the specific RT target hardware documentation for information about supported trigger lines. trigger protocol is the protocol used for trigger action on the PXI bus when the watchdog timer expires. 0 active high 1 active low 2 open collector
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use exception control to treat what is normally an error as no error or to treat a warning as an error. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	watchdogID identifies the watchdog object.
	timeout value returned is the timeout period for the watchdog timer specified in seconds. The timeout period specifies the amount of time that must elapse before the watchdog timer expires. The timeout period is coerced to a value determined from the available timebase and initial count values. The default is 1.
	occurrence is the occurrence associated with the interrupt action that asserts when the watchdog timer expires.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

Watchdog Configure Details

Supported timeout values vary by target. This VI coerces timeout up to the next supported value and returns the actual value as timeout value returned (sec). The value of timeout value returned (sec) is always greater than or equal to the timeout value you specify. The occurrence output of this VI returns a reference to the occurrence action you specify using the expiration actions input.

This VI does not reserve trigger lines, nor does it discriminate between reserved and unreserved trigger lines. If you specify a trigger line that has been reserved elsewhere, the watchdog object overwrites the existing value on the trigger line when the timer expires.

Example

Refer to the Watchdog Reset - RT Engine VI in the labview\examples\Real-Time\RT Watchdog (PXI).llb for an example of using the Watchdog Configure VI.