Timing problem

[Citras]

Hi there, I have problem with timing. As you can see in my excell attachment, the time and the delta time showing every 1000samples(according to samples per channel).

Are there any way to show the time and delta time for every samples at samples per channel of 1000??

One more question is "Is it not possible to use samples per channel less than 1000 (the default is 1000)"? because the time result is wrong when I use samples per channel less than 1000.

[GerdW]

Hi citras,

"the time and the delta time showing every 1000samples"

That's the way you programmed it! You get 1000 samples from your DAQ and then you add just one timestamp (as new column)...

"Are there any way to show the time and delta time for every samples at samples per channel of 1000?"

Yes: add a timestamp for each sample...

"samples per channel less than 1000 (the default is 1000)"? because the time result is wrong"

Read the manual of your DAQ device. And what exactly is "wrong"?

[Citras]

Hi GerdW,

 First of all thanks for your reply

"the time and the delta time showing every 1000samples"

That's the way you programmed it! You get 1000 samples from your DAQ and then you add just one timestamp (as new column)...

"Are there any way to show the time and delta time for every samples at samples per channel of 1000?"

Yes: add a timestamp for each sample...

How to get a timestamp for each sample?

"samples per channel less than 1000 (the default is 1000)"? because the time result is wrong"

Read the manual of your DAQ device. And what exactly is "wrong"?

I am using data translation dt9816 and this what listed on the manual:

A/D conversion time

DT9816: 8MikroS

Channel acquisition time (±½ LSB) 1MikroS

I don't know how it can answer the question

the time result is wrong means:

for example if I use sampling rate 1000 and sample per channel of 1 the time for each sample should be 1ms right? but its not what happen( see my excell attachment )

best regards, citra

[Citras]

sry double post, i forget to attach the excell

[GerdW]

Hi Citras,

"How to get a timestamp for each sample?"

Simple math: t_sample = t0 + i / samplerate ( i is sample index)...

On your DAQ device: I don't work with DT hardware, so cannot talk about theirs limitations...

[Citras]

Hi GerdW,

Simple math: t_sample = t0 + i / samplerate ( i is sample index)...

How to set t0 from 0? and where can I get the i value from?

Could you express it in simple block diagram?

Thank you,

best regards citra

[Citras]

Hi GerdW,

I have test it, and now my only problem is how to get the i ( sample index )?

Best regards, citras

[GerdW]

Hi Citras,

use a (FOR) loop to get the "i"...

[Citras]

Hi GerdW,

I think I nearly get it, the problem now is:

1. How to get the value t0? Because if I set it to 0 the time count reset 0 after 1000 samples. ( it should be continuosly count )

2. How to change the coma value ( I need to set it into 5 value behind to coma, since it was 3)

Best regards, Citras

[Citras]

Sorry I forget to attach the block diagram again