K8055 analogue input data in Labview

Hi all,

I’m having a bit of trouble making a program to read a signal from the analogue pins of the K8055. I’m trying to use it to figure out when the pulses are being sent from an RC reciever.

I’m new to labview so I’m trying to add to vi I got on the Velleman website but I’m struggling to get it to read and save the data. You can find my vi here ozirock.webs.com/K8055_Data_Sample_2.vi.

Basically I want to be able to set the number of samples to be recorded and the frequency at which they are recorded. Push start and get a graph of the data and then save the data.

Any help would be much appreciated.

I made some modifications to the .vi and got the waveform graph working.
Here is the output:

Block diagram:

Sampling interval is 500ms and the number of samples is 21.

Here is the link to download the .vi file: box.net/shared/dqpkak9367
The package includes the latest K8055D.DLL too.

Here is the link to download the whole development package including demo programs and the latest DLL: velleman.eu/distributor/supp … 8055&type=

Here is the link to download improved version of the vi:


Thank you very much for your reply, I was unable to run your vi as I have the 2009 version of labview however I have recreated as best I could please see image below:

I have a question, is it possible to make the delay less than 1ms, from testing there I see no difference in the if the wait is set to 1 or 0.1, does it round to the nearest whole number?

I’m trying measure an RC servo signal which should give a pulse every 20 ms and the length of that pulse determines the position of the servo so I am expecting a square wave but I’m getting spikes. This is why I think I need to reduce the time between samples.

The USB communication polling interval is about 10ms.
The analog data can be read every 10ms from the K8055 card.
Maybe this is the reason why you are getting the spikes only.

I made a test: Using interval value less than 5ms gives no improvement to the result.
The sampling interval is anyhow 10ms.

I made the test with the second version of the VI.
The first version have a lot of “overhead” and the sampling interval seems to be about 35ms.

Ah okay so the communication between the board and computer just can’t happen fast enough for what I want, it’s a pity but at least I’ve learnt a bit about using Labview with the board so thank you very much for your help :slight_smile: