Understanding DAQmx Functions

[Kobi_K]

Hi , 

I have a few questions regarding the DAQmx Library in CVI.

1.While working with DAQ Devices I'm opening a Task and a channel to some device For example AO1.

I'm setting it to work with an external hardware trigger and defining all the needed parameters , starting the task doing the analog output and stopping the task.

so far so good , but if I want to repeat the same task without setting all the parameters again how can I do that ? Does the device remember it's configuration ?

the thing I need is to make a task that will repeat it self for days with out setting parameters because it takes time from each test,  time I don't have.

2.NI Function time cycle , is there any document that show how much time it takes for each function ?

3.  DAQmxErrChk (DAQmxCreateAOVoltageChan(gAOtaskHandle,AOchan,"",AOmin,AOmax,DAQmx_Val_Volts,NULL));

the values for AOmin & AOmax : if I'm setting it to -10 : + 10 , is it possible to change it with out creating a new channel ?

[RobertoBozzolo]

As per your Q1, provided you do not clear the tast you can start and stop it many times. I have used this method for digital output: I suppose it is the same for analog output.

[Kobi_K]

Hi Roberto , 

Iv'e tried it , it works fine.

Any idea about my other questions ?

[RobertoBozzolo]

While I have no idea about your second question, I suppose you can use DAQmxSetChanAttribute with DAQmx_AI_Max and DAQmx_AI_Min attributes respectively. I have no DAQ device at present to make a real test and see if changing these attributes with the task started raises any error or actually does not changes settings at all (that's why I didn't post this before), but you can try it in minutes.

[Kobi_K]

You right it's work fine , i didn't knew if it's ok to change this val while running but it's ok.

As to Q2 i'll test is myself with the PC Clock or the timer.

Thank you.