Reads one or more 8-bit unsigned integer samples from a task that contains one or more digital input channels. Use an instance that reads 8-bit unsigned integers for devices with up to eight lines per port.
task in is the name of the task that the operation applies.
number of samples per channel specifies the number of samples to read.
If you leave this input unwired or set it to -1, NI-DAQmx determines how many samples to read based on if the task acquires samples continuously or acquires a finite number of samples.
If the task acquires samples continuously and you set this input to -1, this node reads all the samples currently available in the buffer.
If the task acquires a finite number of samples and you set this input to -1, the node waits for the task to acquire all requested samples, then reads those samples. If you set the Read All Available Samples property to TRUE, the node reads the samples currently available in the buffer and does not wait for the task to acquire all requested samples.
timeout specifies the amount of time in seconds to wait for samples to become available. If the time elapses, the node returns an error and any samples read before the timeout elapsed. The default timeout is 10 seconds. If you set timeout to -1, the node waits indefinitely.
If you set timeout to 0, the node tries once to read the requested samples and returns an error if it is unable to.
error in describes error conditions that occur before this node runs. This input provides standard 'error in' functionality.
task out is a reference to the task after this node runs.
data returns a 2D array of 8-bit unsigned integer samples. Each row corresponds to a channel in the task. Each column corresponds to a sample from each channel.
error out contains error information. If error in indicates that an error occurred before this node ran, error out contains the same error information. Otherwise, error out describes the error status that this node produces.
Where This Node Can Run:
Desktop OS: Windows
FPGA: LabVIEW NXG does not support FPGA devices
Web Server: Not supported in VIs that run in a web application