Timing measurement of a Digital Output and Digital input using flat Sequence structure

[pnulty]

Hi Guys,

i am looking to do a very basic task in labview but i am running into difficulty. i will try to explain as accurately as possible.

I want to create a Digital output  which my transmitting circuit is connected to P0.0 in frame 1 that will start a timer when the signal in frame two is received Digital input it calculates a time difference between sent signal and received signal. I have added a while loop that while the condition is not true it continues to check until it is. My vi is below but I cannot get it to work. Please help.

here is the vi hopefully someone can help

[crossrulz]

How accurate of measurements do you need?  You will not get anything really accurate using a Windows clock.  You may need to set up a counter along with some external circuitry to get what you want.

[pnulty]

Hi.

My circuits consist of the following.

Tx: LM555 generating a 40kHz which is connected to an AND gate which i was using to start the sequence.

Rx: circuit is connected to an LM567 which hen the PLL detects 40kHz drops the output voltage of pin 8 to 0v.

It is this time between the intial Tx sending and the recieving of the 40kHz pulse Rx that i need to capture.

[pnulty]

also my NI device is a usb 6216

[SFuller]

Hi,

I had a quick look over your code and noticed a few things that you need to implement:

• Swap the 'Subtract' inputs to find the difference in time between the two.
• Add a piece of code between the data output which sends a false to the 'Equal to' when the current data out equals false.

I hope this helps!

[pnulty]

Hi,

still having trouble in getting any timing measurement at all from circuits. attached is the latest Vi