Configuration of USB 6008

[Sergey(PSU)]

Hi,

how to configure USB 6008 (AI range, rate of readungs etc) in MAX. I have got 7.5 drivers and when I go in a MAX to Devices and interfaces/NI-DAQmx devices/USB-6008: Dev2 and right click on it and Properties is gray, so I can not change it.

Is there another way to configure settings?

Thanks. Sergey.

[AdamB]

Hi Sergey,


To be able to define the AI range and rate of readings you need to create a new DAQmx task.

If you:
1.Navigate to MAX.
2.Expand Data Neighborhood
3.Right click on DAQmx tasks
4.Select Create new NI-DAQmx Task

This will allow you to define each of the inputs you need.

The properties that you are trying to access don't exist with these cards. They are to add on connected devices and "breakout" boxes.


I hope this helps you
I am now monitoring this forum so if you need any more information, post back on this forum.

Regards

AdamB
National Instruments

[Sergey(PSU)]

Thanks AdamB,

it helped.

Sergey.

PS: I have a question, it is not connected to the name of the topic, sorry. In a Labview7.1 I need to set AO value to zero for some amount of time when AI signal reaches some maximum (for  example set it to zero for 30 seconds or until AI reading drops back to some value). What is the best way to do it. I need it to switch off Pump when pressure becomes too high and then switch it on back when pressure stabilizes.

Message Edited by Dr Zhdanov on 09-22-2005 04:16 PM

[AdamB]

What you need to do is configure an analog output and an analog input.

Initiate and start the two tasks outside of a while loop

Inside the loop aquire the Analog input at the same time as reading in the analog signal from the pressure device

Then you just need to use a case structure to decide if the value is too high.  If this is the case then you put a new value (zero) to the AO.

At the same time you need to record the time.

Using another level of case structures you can evaluate the time that Ao has been at zero. Once 30 seconds has passed.  resume the previous A0 values.

Another method is to use a state machine. (Search examples in Labview if you don't understand)

with cases

INITIALISE = initialises the system - next state = Normal

NORMAL = Running normaly - State HIGH if the pressure goes above a certain value

HIGH = changes A0 to zero and monitors the time at A0 - Next state is Normal after 30 seconds (configurable)

and STOP = Stops the program on a user input, or error ocurring. also closes off all the DAQmx tasks.

This should give you the functionality you desire. 

Regards

AdamB

p.s I have just recieved your e-mail regarding the Ao and Ai.

I will e-mail you back ASAP

Thanx

[Sergey(PSU)]

Thanks AdamB for your responce.

I ahve tried to understand what you suggested and failed.

I have some critical pressure value. When the pressure reaches its level I use boolean SELECT to choose between non zero value and zero value for AO. If I will use Case structure it will be True case while Pressure value is higher than Critical value. As soon as it becomes lower it will be False case. If I will start some Elapsed Time for example inside false case will it work when the case is already True?

I am completely confused.

I've put example of my program. It is not very complicate. The things I am intersted in are in red colors on a bottom of block diagram. Please take a look and if you can insert your changes (or create separate examle) I will be very gratefull.

Thanks. Sergey.