Simulink Analog Input block size problem

Hi all,

I am trying to acquire data using a NI-PCI-6034E device. By using the Analog Input block I should be able to get what I want. The problem is that there is a minimum requirement of the block size of 2 which if use a scope to look at data acquired real time, two signals sort of stacked together for every two time interval.

For example, if I am to acquire the data for 1 seconds at the sampling rate of 1000, I should expect to see one point for each millisecond. But I am actually seeing two points having a length of two millisecond acquired simultaneously...

Is there a way to get around this problem?

I tried to increased my block size to the number of points I expect to get. For instance, my block size will be 1000 for a sampling rate of 1000 acquiring for 1 second. It sort of worked but then for each duration, I am getting an array having third index...

For the same example aforementioned, I should expect to see 1000 data but end up seeing 2000 data within 1 second...

Please help me!!!

Thanks!

[Cole Feagler]

I have the same issue - can anyone please provide some insight?

Answer 1

[Marco Perozzi]

Hi, i had the same problem, if you use the block "Time Scope" instead of "Scope" you shoudn't have the problem anymore. Sincerely i don't know why but for me worked. Moreover it's better if you don't use a numer of blocks less than 1/10 of sampling rate.

Answer 2

[Mirroyal Ismayilov]

Hello,

You need to sum the signals up and multiply the gain of 0.5 in order to get the same value with one signal.