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Acquire Non-Clocked Digital Data

This example shows how to read digital data using two channels on an NI USB-6255

Discover NI devices connected to your system and find the ID for the NI 6255:

dev = daqlist("ni")
dev =

  3×4 table

    DeviceID                Description                  Model             DeviceInfo       
    ________    ___________________________________    __________    _______________________

     "Dev1"     "National Instruments(TM) USB-6255"    "USB-6255"    [1×1 daq.ni.DeviceInfo]
     "Dev2"     "National Instruments(TM) USB-6509"    "USB-6509"    [1×1 daq.ni.DeviceInfo]
     "Dev3"     "National Instruments(TM) USB-6211"    "USB-6211"    [1×1 daq.ni.DeviceInfo]

Create a DataAcquisition object and add two input lines from port 0 on Dev1:

d = daq("ni");
ch = addinput(d,"Dev1","Port0/Line0:1","Digital")
ch = 

    Index    Type     Device       Channel       Measurement Type    Range           Name       
    _____    _____    ______    _____________    ________________    _____    __________________

      1      "dio"    "Dev1"    "port0/line0"      "InputOnly"       "n/a"    "Dev1_port0/line0"
      2      "dio"    "Dev1"    "port0/line1"      "InputOnly"       "n/a"    "Dev1_port0/line1"

Acquire a single scan of digital data from both channels:

data = read(d,"OutputFormat","Matrix")
data =

     1     0