NI DAQMX Watchdog Attributes

Watchdog Attributes

See how to get and set attributes.

• DAQmx_Watchdog_Timeout
• Expiration Trigger
  • DAQmx_WatchdogExpirTrig_Type
  • DAQmx_WatchdogExpirTrig_TrigOnNetworkConnLoss
  • Digital Edge
    • DAQmx_DigEdge_WatchdogExpirTrig_Src
    • DAQmx_DigEdge_WatchdogExpirTrig_Edge
• Expiration States
  • Digital Output
    • DAQmx_Watchdog_DO_ExpirState
  • Analog Output
    • DAQmx_Watchdog_AO_OutputType
    • DAQmx_Watchdog_AO_ExpirState
  • Counter Output
    • DAQmx_Watchdog_CO_ExpirState
• Status
  • DAQmx_Watchdog_HasExpired

DAQmx_Watchdog_Timeout

Data Type:	float64
Description:	Specifies in seconds the amount of time until the watchdog timer expires. A value of -1 means the internal timer never expires. Set this input to -1 if you use an Expiration Trigger to expire the watchdog task.

You can get/set/reset this attribute using:   DAQmxGetWatchdogAttribute   DAQmxSetWatchdogAttribute   DAQmxResetWatchdogAttribute

Expiration Trigger

DAQmx_WatchdogExpirTrig_Type

Data Type:	int32
Description:	Specifies the type of trigger to use to expire a watchdog task.

Valid values

DAQmx_Val_DigEdge	10150	Trigger on a rising or falling edge of a digital signal.
DAQmx_Val_Time	15996	Trigger when a specified time is reached.
DAQmx_Val_None	10230	Disable the trigger.

You can get/set/reset this attribute using:   DAQmxGetWatchdogAttribute   DAQmxSetWatchdogAttribute   DAQmxResetWatchdogAttribute

DAQmx_WatchdogExpirTrig_TrigOnNetworkConnLoss

Data Type:	bool32
Description:	Specifies the watchdog timer behavior when the network connection is lost between the host and the chassis. If set to true, the watchdog timer expires when the chassis detects the loss of network connection.

You can get/set/reset this attribute using:   DAQmxGetWatchdogAttribute   DAQmxSetWatchdogAttribute   DAQmxResetWatchdogAttribute

Digital Edge

DAQmx_DigEdge_WatchdogExpirTrig_Src

Data Type:	char*
Description:	Specifies the name of a terminal where a digital signal exists to use as the source of the Expiration Trigger.

You can get/set/reset this attribute using:   DAQmxGetWatchdogAttribute   DAQmxSetWatchdogAttribute   DAQmxResetWatchdogAttribute

DAQmx_DigEdge_WatchdogExpirTrig_Edge

Data Type:	int32
Description:	Specifies on which edge of a digital signal to expire the watchdog task.

Valid values

DAQmx_Val_Rising	10280	Rising edge(s).
DAQmx_Val_Falling	10171	Falling edge(s).

You can get/set/reset this attribute using:   DAQmxGetWatchdogAttribute   DAQmxSetWatchdogAttribute   DAQmxResetWatchdogAttribute

Expiration States

Digital Output

DAQmx_Watchdog_DO_ExpirState

Data Type:	int32
Description:	Specifies the state to which to set the digital physical channels when the watchdog task expires. You cannot modify the expiration state of dedicated digital input physical channels.

Valid values

DAQmx_Val_High	10192	Logic high.
DAQmx_Val_Low	10214	Logic low.
DAQmx_Val_Tristate	10310	High-impedance state. You can select this state only on devices with bidirectional lines. You cannot select this state for dedicated digital output lines. On some devices, you can select this value only for entire ports.
DAQmx_Val_NoChange	10160	Do not change the state of the lines. On some devices, you can select this value only for entire ports.

You can get/set/reset this attribute using:   DAQmxGetWatchdogAttribute   DAQmxSetWatchdogAttribute   DAQmxResetWatchdogAttribute

Analog Output

DAQmx_Watchdog_AO_OutputType

Data Type:	int32
Description:	Specifies the output type of the analog output physical channels when the watchdog task expires.

Valid values

DAQmx_Val_Voltage	10322	Voltage output.
DAQmx_Val_Current	10134	Current output.
DAQmx_Val_NoChange	10160	Expiration does not affect the port. Do not change the state of any lines in the port, and do not lock the port.

You can get/set/reset this attribute using:   DAQmxGetWatchdogAttribute   DAQmxSetWatchdogAttribute   DAQmxResetWatchdogAttribute

DAQmx_Watchdog_AO_ExpirState

Data Type:	float64
Description:	Specifies the state to set the analog output physical channels when the watchdog task expires.

You can get/set/reset this attribute using:   DAQmxGetWatchdogAttribute   DAQmxSetWatchdogAttribute   DAQmxResetWatchdogAttribute

Counter Output

DAQmx_Watchdog_CO_ExpirState

Data Type:	int32
Description:	Specifies the state to set the counter output channel terminal when the watchdog task expires.

Valid values

DAQmx_Val_Low	10214	Low logic.
DAQmx_Val_High	10192	High logic.
DAQmx_Val_NoChange	10160	Expiration does not affect the state of the counter output. The channels retain their states at the time of the watchdog timer expiration, and no further counter generation runs.

You can get/set/reset this attribute using:   DAQmxGetWatchdogAttribute   DAQmxSetWatchdogAttribute   DAQmxResetWatchdogAttribute

Status

DAQmx_Watchdog_HasExpired

Data Type:	bool32
Description:	Indicates if the watchdog timer expired. You can read this property only while the task is running.
Restrictions:	Not Settable

You can get this attribute using:   DAQmxGetWatchdogAttribute