Select Function
- Updated2023-02-17
- 4 minute(s) read
Select Function
Specifies whether digital pattern instrument channels are controlled by the PPMU, Digital, disconnected, or off. Changes take effect immediately.
Inputs/Outputs
session in
Instrument session obtained from the niDigital Initialize with Optionsnode.
channel list
List of channel names or list of pins. Do not pass a mix of channel names and pin names.
An empty string denotes all digital pattern instrument channels.
Specify channel names using the form PXI1Slot3/0,2-3 or PXI1Slot3/0,PXI1Slot3/2-3, where PXI1Slot3 is the instrument resource name and 0, 2, 3 are channel names.
To specify channels from multiple instruments, use the form PXI1Slot3/0,PXI1Slot3/2-3,PXI1Slot4/2-3. The instruments must be in the same chassis.
Site Considerations and Syntax
Pin names and pin groups apply to all enabled sites, unless the pin name explicitly specifies the site. You can specify a pin in a specific site using the form siteN/pinName, where N is the site number. This node ignores pins that are not mapped to the digital pattern instrument.
function
Value that specifies whether to disconnect the pins, or use the PPMU or pin driver to control the pins.
| Digital |
The pin is connected to the driver, comparator, and active load functions. The PPMU is not sourcing, but can make voltage measurements. The state of the digital pin driver when you change the selected function to Digital is determined by the most recent call to the niDigital Write Staticnode or the last vector of the most recently executed pattern burst, whichever happened last. Use the niDigital Write Staticnode to control the state of the digital pin driver through software. Use the niDigital Burst Patternnode to control the state of the digital pin driver through a pattern. Set the select digital function input of the niDigital Burst Patternnode to True to automatically switch the selected function of the pins in the pattern burst to Digital. |
| PPMU |
The pin is connected to the PPMU. The driver, comparator, and active load are off while this function is selected. Call the niDigital PPMU Sourcenode to source a voltage or current. The niDigital PPMU Sourcenode automatically switches the selected function to the PPMU state and starts sourcing from the PPMU. Changing the selected function to Disconnect, Off, or Digital causes the PPMU to stop sourcing. If you change the selected function to PPMU using the niDigital Select Functionnode, the PPMU is initially not sourcing. Note You can make PPMU voltage measurements using the niDigital PPMU Measurenode from within any selected function. |
| Off |
The pin is electrically connected, and the PPMU and digital pin driver are off while this function is selected. |
| Disconnect |
The pin is electrically disconnected from instrument functions. Selecting this function causes the PPMU to stop sourcing prior to disconnecting the pin. Caution In the Disconnect state, some I/O protection and sensing circuitry remains exposed. Do not subject the instrument to voltage beyond its operating range. |
| NIDIGITAL_VAL_RIO |
Yields control of the specified pin(s) to LabVIEW FPGA. |
error in
Error conditions that occur before this node runs.
The node responds to this input according to standard error behavior.
Default value: No error
session out
Handle that identifies the session in all subsequent NI-Digital node calls.
error out
Error information.
The node produces this output according to standard error behavior.
Alternate Ways to Select Function
By default, the niDigital Burst Pattern node automatically changes the function to Digital for the pins in the pattern. The niDigital PPMU Source node always changes the function to PPMU for the pins in the channel list automatically.