You can create a virtual (or simulated) device using the NI Measurement & Automation Explorer and attach the device to an Embed diagram to modulate and display signals.
1. Launch NI-MAX.
2. Right-click Devices and Interfaces to Create New device.
3. Choose Simulated NI-DAQmx Device or Modular Instrument, then click Finish.
4. Choose a device from the NI-DAQmx Simulated Devices menu tree.
5. Communicate with the simulated device from Embed.
a. Start Embed and insert an NI block (Blocks > Real Time) into the work area.
b. Right-click the block.
c. In the dialog, select the device from the Device # dropdown. That is, select a number that corresponds to your device. Then select a Type.
d. Click OK or press ENTER.
e. Connect either a Signal Producer or Consumer block to the NI block and click Go.