Read Waveform (Read Waveform (WDT)) (G Dataflow)

Instrument session obtained from the Initialize Acquisition Session node, the Initialize Generation Session node, or the Initialize External Calibration node.

Parameter that specifies whether the timestamp for the waveform data is relative or absolute.

The specified channels from which to read waveform data.

You must assign all channels that you want to read using the niHSDIO Assign Dynamic Channels node before selecting those channels with this parameter.

NI-HSDIO reads waveform data in the order that you list channels in this parameter, not in the order that those channels are listed in the niHSDIO Assign Dynamic Channels node. If you leave this parameter blank, NI-HSDIO reads all channels that were set using the niHSDIO Assign Dynamic Channels node.

Specify multiple channels by using a channel list or a channel range. A channel list is a comma (,) separated sequence of channel names (for example, 0,2 specifies channels 0 and 2). A channel range is a lower bound channel followed by a hyphen (-) or colon (:) followed by an upper bound channel (for example, 0-2 specifies channels 0, 1, and 2).

The specified number of samples to fetch.

If you specify a value for samples to read that is greater than the number of samples in the device memory, NI-HSDIO returns the samples that are acquired after max time milliseconds. Setting this parameter to -1 acquires the samples per record specified in the niHSDIO Configure Acquisition Size node.

The time, in milliseconds, allotted for the node to complete before NI-HSDIO returns a timeout error.

If you set the value to -1, the node never times out. If you set this parameter to 0, the node returns immediately with up to the number of samples specified in samples to read.

If samples to read is greater than the number of samples in the device memory and all the available samples are acquired before a timeout, NI-HSDIO returns the available samples.

Default: 10000

Parameter that specifies which record you want to fetch from onboard memory.

Error conditions that occur before this node runs.

The node responds to this input according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error	error in contains an error
If no error occurred before the node runs, the node begins execution normally. If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.	If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

Default: No error

Handle that identifies the session in all subsequent node calls.

The session out parameter is obtained from the Initialize Acquisition Session node or the Initialize Generation Session node.

The returned acquired waveform.

The number of samples that were successfully acquired and transferred into data.

Error information.

The node produces this output according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error	error in contains an error
If no error occurred before the node runs, the node begins execution normally. If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.	If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.