Frequency Measurement

This example shows how to measure input signal frequency using Simulink Desktop Real-Time™. The measured signal is connected to the counter input of your data acquisition board. Counter Input block is configured to reset counter each sample-hit after counter read. Dividing counter value by sample time gives input signal frequency.

Note: To run this model, you must have a data acquisition board with counter input connected to your computer.

How to run this model in Normal Mode

  1. Open the Counter Input block and select your data acquisition board. If there's no board installed, install it using the Install new board button.

  2. Double-click the orange button to switch to Normal Mode if needed.

  3. Start the real-time execution using Simulation->Run.

How to run this model in External Mode

  1. Open the Counter Input block and select your data acquisition board. If there's no board installed, install it using the Install new board button.

  2. Double-click the orange button to switch to External Mode if needed.

  3. Start the real-time execution using Simulation->Run. The model will automatically build, connect to Simulink in External Mode and start.

Open the model

open_system(fullfile(matlabroot,'toolbox','sldrt','sldrtexamples','sldrtex_counter'));

Close open Scopes

close_system(find_system(gcs ,'BlockType', 'Scope'));

Clean up

clear
close all
bdclose all

See Also