niSwitch Configure Scan Trigger VI
- Updated2025-10-06
- 5 minute(s) read
Configures the scan triggers for the scan list established with the niSwitch Configure Scan List VI.
Refer to Devices to determine if the switch module supports scanning.
This VI sets the location where the switch expects to receive an input trigger to advance through the scan list. This VI also sets the location where it generates a scan advanced signal after it completes an entry in the scan list.
Related Topics

Inputs/Outputs
scan delay (0.0s)
—
scan delay specifies the minimum length of time you want the switch device to wait after it creates a path until it asserts a trigger on the Scan Advanced Output channel. NI-SWITCH uses this value to set the Scan Delay property. The scan delay is in addition to the settling time. Default value: 0.0 (seconds)
instrument handle
—
instrument handle identifies a particular NI-SWITCH session established with the niSwitch Initialize With Topology VI, the niSwitch Initialize With Options VI, or the niSwitch Initialize VI.
trigger input (External)
—
trigger input specifies the trigger source you want the switch module to use during scanning. NI-SWITCH uses this value to set the Trigger Input property. The default value is External. The switch module waits for a trigger at the specified location when it encounters a semicolon in the scan list. When the trigger occurs, the switch device advances to the next entry in the scan list and waits for a trigger from the location specified in trigger input.
scan advanced output (External)
—
scan advanced output (External) specifies the output terminal for the Scan Advanced Output trigger signal. NI-SWITCH uses this value to set the Scan Advanced Output property. The default value is External. After the switch processes each entry in the scan list, it waits the length of time specified in scan delay and then asserts a trigger on the line specified in scan advanced output.
error in (no error)
—
error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
instrument handle out
—
instrument handle out identifies a particular NI-SWITCH session established with the niSwitch Initialize With Topology VI, the niSwitch Initialize With Options VI, or the niSwitch Initialize VI and used for all subsequent NI-SWITCH calls.
error out
—
error out contains error information. This output provides standard error out functionality. |
Details
For synchronous scanning, set scan advanced output to None and define trigger input. For handshaking, trigger input and scan advanced output must be set.
Triggers generally originate from the SCXI or PXI trigger bus, the terminals on the front connector of the switch module, or the AUX connector on the rear of the switch module (referred to as the rear connector and supported by SCXI only).
When scanning a module that is not directly cabled to the trigger from its own front or rear connector, use the niSwitch Route Trigger Input VI and/or the niSwitch Route Scan Advanced Output VI to route the triggers on the cabled module to one of the backplane lines. When using these VIs to route triggers to the backplane, specify the backplane trigger location when calling the niSwitch Configure Scan Trigger VI (even if it is the module cabled to the trigger source).
scan delay (0.0s)
—
instrument handle
—
trigger input (External)
—
error in (no error)
—
instrument handle out
—
error out
—