detecting loss of watchdog (square wave) from my device under test

[freekquency]

Need help in developing a way to detect the loss of a watchdog (which is a digital square wave) through LabVIEW - from my device under test (project).  So, I need to monitor the square wave (heart beat) from the device.  Then, act on the loss of the square wave.  So that I may determine what happened.  I would then read things through LabVIEW,  like supply voltages and other signal to capture what happened.

This is the essence of may experiment:

Currently working with Arduino Uno R3

Thanks All...

[AustinStanton]

First of all, you should use LINX to communicate with the Arduino using LabVIEW. I have created a simple VI that I think does what you want it to do. This VI will constantly read the voltages and record them to a graph. The first block inside the while loop is called "Read Pulse Width" and it is used to read the square wave. When the square wave dies it will output a pulse width of 0 which will change the case structure so that starts recording the values after that point onto a different graph and will set an error boolean to true. That way you will be able to see what happens directly before and after your heart beat dies. 
 

Let me know if that's what you want

Austin Stanton

watchdog_record.vi

[freekquency]

Austin, thank you so much for your time...  I will try this weekend and let you know...

Patrick

[freekquency]

Austin, Did a quick test of your VI.  Working but would like a different Y axis timing (faster).  However, I want to better learn the fundamentals of the Linx pulse width read VI.  So I am going to test various scenarios with a function generator.  Then once the pulse width VI is intuitive.  I will move onto case structures and waveform presentation.  Will keep you posted.

Thanks again,

Patrick

[AustinStanton]

Goodluck, let me know if you have any other questions.

Austin Stanton