Data Logging and Saving Problems

[PDM]

I'm using SignalExpress 2009, v 3.5.0 and struggling with saving my data on multiple fronts:

(1) I'd like to run my analog data acquisition from a USB-6009 at 10 or 20Hz to process and display data in real time on the Data View tab, while logging some of the processed data at 1Hz. Ultimately, I'm looking for an ASCII text file of my multiple 1Hz signals that charts nicely in Excel. When I set up the logging function to grab my data at 1Hz, I seem to get multiple samples saved each second or all of the 20Hz data. My Start Conditions are set to 1 second, and Stop Conditions are set to Duration and a number less than 1 second (setting to a value less close to the sample period still gives multple readings). Perhaps I'm not setting up the Stop Conditions properly. Lastly, with this logging approach, when I go to display the previously logged data, the program systematically crashes before I can export anything to Excel (I'm assuming some pilot error here that I haven't figured out yet).

(2) As an alternative, I could add a Save to ASCII step in my project that stores the several data items (along with a time-stamp) once per second to ensure data isn't lost after a program crash (though would seem to have to change my DAQ acquisition to 1Hz). However, the step setup options window I see doesn't offer the options listed when I search for help in the SignalExpress Help instruction. Specifically there's no X Value Column option available and the Export file type window is grayed out (defaults to Generic ASCII (.txt), is is okay, but I need the other options). My only choices undre File Settings are Export file path, If file already exists, and Delimiter. Any suggestions?

Sorry for the long string of issues, but something that I was assuming I could work out on my own by reading the manual and searching this message board isn't working out. 

Thanks,

Paul

[Ryan_T]

Hi Paul,

I am having dificulty replicating the issue that you see in the second portion of the post. Do you have the Full version of SignalExpress or do you have the Limited Edition?  Also, could you please post your project file with the code that you discuss in both parts 1 and 2 of your post?  That way I can better understand what you are trying to do and how you are currently accomplishing it.

Thanks

[PDM]

Hi Ryan,

I'm using the Full version.

I've attached two project files - one illustrating my ascii write issues (along with a screen shot of my configuration options), and one for the recording setup that I'm trying that results in bursts of the higher rate of sampled data rather than one sample each second.

Hope this helps in suggesting what I'm doing wrong.

Paul

[Ryan_T]

Hi Paul,

The reason that you are not able to selcet the file options that you are used to is because of the data type that you are sending to the file.  It is of type double and we need it to be of type waveform in order to have those options.  In order to accomplish this we need to change the Acquisition Mode in the Timing Settings section for the DAQmx Acquire task.  We should change it to either N Samples or Continuous Samples and then you will have the options for which you are searching. Getting the application to work with these Timing Settings might help with the other issue as well.