You can verify that an SDRu block is connected to USRP® hardware by examining the block mask.
Open model with an SDRu Transmitter or SDRu Receiver block.
To open the block mask, double-click the block.
If the block is connected, then the Hardware panel shows values for the following parameters:
Minimum center frequency
Maximum center frequency
Gain step size
If the block is not connected, the Hardware panel shows the following message: "No device found at the specified IP address. Connect a USRP device to your host computer at the specified IP address or continue to work in off-line mode. You may need to close and reopen the dialog to detect the device."
A block can connect to only one subdevice (transmitter or receiver) at a time, on the same IP address.
To verify that your SDRu System object™ is connected to the USRP® hardware, follow these steps:
Construct a Receiver or Transmitter System object:
Enter the following command:
a = findsdru()
a = struct with fields: Platform: 'N200/N210/USRP2' IPAddress: '192.168.30.7' SerialNum: 'F2A02F' Status: 'Success'
This function finds the IP address and status of each USRP® radio connected to the host.
ans = 192.168.30.7
ans = Success
A System object can connect to only one subdevice (transmitter or receiver) at a time, on the same IP address. If you change property values of an SDRu System object and display the actual values, the object connects and then immediately disconnects once the properties are displayed. SDRu System objects connect to a subdevice when you call the object as a function (or call the step method), and stays connected until you call the release method.
 USRP, USRP2, UHD, and Ettus Research are trademarks of National Instruments Corp.