Multiple data acquisition NI DAQmx

[Soucha]

Hello,

I need your help, I want to recover analog signal from laser and also measure temperature from a thermocouple in the same time. I had an error when I put two DAQmx and I think the reason is that the DAQmx has only one ADC and can't do different analog input simultaniously.

My question, do you have a solution to obtain the signal and temperature with only one DAQmx by having the choice to order them ( for exemple signal way 0 and temperature way 1) ?

I add a pictures of my programm; I can't add the way to recover temperature.

Thank you,

[GerdW]

Hi Soucha,

you already found the way to get the tension value using that FromDDT function with an additional input of "0" for the first channel.

But then you failed to use the very same FromDDT function to read the value from channel 1 (aka temperature) in that marked place? Even though you already read that temperature value in two other places correctly?

Hint: use AutoCleanup and you will see your failure immediatly!

Btw. I would not use so many DDT wires…

[Soucha]

Hi GerdW,

Thank you for your response,  I add another picture.

My problem is that I can't have the both way simultaniously, For example I'm able to recover the temperature of thermocouple alone  (not correctly) but not as the same time as the analog signal which is displacment here..

I put a lot of DDT to change the way, but with temperature it's not change because i recover a table one D and not scalar so you're right.

I have no error because I recover the same signal in the same output ( displacement = temperature ) because I can't change the way ( 0-1).

I also tryed to put two daqmx but an error appeared and after research I found thar DAQmx has only one ADC.

S.C

[Soucha]

I can't execute my program, do you have another solution to this ?

Picture attached.

S.C

[GerdW]

Hi Soucha,

I can't execute my program, do you have another solution to this ?

Just remove that error!

You try to use the same resource (atleast) twice in your VI. Most probably it's those two DAQAssistents.

Why don't you learn the DAQmx basics to get rid of DAQAssistent ExpressVI and DDT wires?

[Soucha]

Hello,

Thank you for your response, I find the error but I can't work without 2 DAQmx, because the way in one DAQmx is for one application and not two, I will follow the link you sent me thanks.

Cordially,

SC

[GerdW]

Hi Soucha,

I find the error but I can't work without 2 DAQmx,

A DAQmx task can contain more than just 1 DAQmx channel: just create a task with 2 or more channels…

(Again: see the linked DAQmx basics above. It also explains the DAQmx terminology!)

[Soucha]

Hi GerdW,

Yes I know that it has 7 input for analog input. But when I add temperature ( thermocouple) and tension (V) I just recover the tension and not the temperature because the DDT does'nt allow me to put the output channel. Thank you

Cordially,

[Soucha]

I found in the link you sent me that we can do what I want on the DAQ assistan, I have to do it mannually, thank you for your answer ^^

Cordially,

SC

[Soucha]

Hi GerdW,

Do you think that my connections are bad ? I add a picture of my connection diagramm, may be it can help you to understand my probleme, I have voltage + temperature in one daq assistant, but when I recover the input to make a wave form I just can recover the voltage signal and not both..

Cordially,