number of samples per second

[Dennis_Knutson]

Don't use AI Single Scan. Single means 1. To take multiple readings on multiple channels with hardware timing, use AI Acquire Waveform. Look at the shipping examples (Help>Find Examples) and read the LabVIEW Measurements Manual (Help>Search the LabVIEW Bookshelf).

[radhika]

Hi

From my understanding , itseems that we are using Traditional NI DAQ.

What if we use NI DAQmx?

Can i have 2 codes (separately) one using Traditional NI DAQ and the other using NI DAQmx ?

Thanks

radhika

[Dennis_Knutson]

You can only use one or the other and I would recomend using DAQmx. That is the only driver that has a future.

[radhika]

Hi....

I did the transition from Traditional NI DAQ to NI DAQmx.

While running the program with DAQmx i got the error ,

89130 : Error occurred at DAQmx read - Device not available for routing.

I resetted the Traditiona NI DAQ devices and i also used DAQmx reset device.vi at the end of the sequence.

How to rectify this error??

Thanks

radhika

[Dennis_Knutson]

You're going to have to post your code. I have never used the DAQ reset device as I never had a reason to do so. If you placed it after a clear task, it may be invalid to use it then. Where did you see an example that used the reset device?

Message Edited by Dennis Knutson on 04-05-2007 10:33 PM

Message Edited by Dennis Knutson on 04-05-2007 10:33 PM

[xseadog]

Hi Radhika,

have you read the following thread with regard to reseting DAQ devices?

http://forums.ni.com/ni/board/message?board.id=250&message.id=16124&requireLogin=False

As Dennis mentioned, upload you code else this will take a month of Sunday to solve

xseadog

[radhika]

Hi,

I saw how to use the traditional NI DAQ and the NI DAQmx using one DAQ board in the NI website only.

here is the link..............

http://zone.ni.com/devzone/cda/tut/p/id/3021

i figured my error in the code , i didnot connect the input device correctly.

Now it works fine.

Anyways thanx for ur help.

thanks

radhika

[radhika]

HI,

Again reverting to my initial issue of sampling the data............

so now i am going to sample the data by hardware timing....well i used all daqmx functions to create , read channels...........

Here are my issues,

1.Even if i change the sample rate and the number of samples/per channel.................the values in the daqmx timing (sample clock) remains 1000 & 1000 always..................so how can i have different sampling rates????

and

2.also i get data from the channels at variuos parts of the program and also in several subvi's ....right now i have used task name constant to carry over the task ( from the initial place DAQmx create virtual channel.vi) to all the places..but it made my program run very slow.........................

Only now i have come to the real issues................

Any help?????

Thanks

radhika

[radhika]

here is my example code.............

[Dennis_Knutson]

I have no idea what you mean that the DAQmx timing remains the same. I can change the front panel and change them to whatever rate and number of samples.

I can't comment on your subVI. It guess I don't understand at all what you are trying to do. To set up for multiple samples and then use only the first sample and discarding the rest seems overly complicated. Maybe you really don't need to do hardware timing if you only wnat one sample at a time. You also have the option of using a single data acquisition loop and writing the data the data to a queue or even a global variable so that the other parts of the program can retrieve the data (not do another DAQmx read) at any time.

Look at some of the shipping examples and design patterns (File>New...) related to consumer/producer and master/slave.