ODBC Output of Frequency value from Counter In

[Adam@gmr]

Hi,

I am having trouble outputting the frequency found on a Counter input channel to Excel when I use the ODBC Output function with DASYLab v 9.0.1.  I am using a DaqBoard2000 and the DaqBoard2K0 hardware driver.  Settings in the Experiment Setup: 10KHz/ch, 2000 Block size, and a continuous 16384 KByte buffer.  The Time based Setup: DASYLab Sampling Rate 500kHz, Blocksize 32768 (Auto).  Basically the worksheet is setup as: Counter in (measuring Frequency) ==> Counter (setup on one sample per block) ==> Scale-2 point (0=0, 2880 = 3600) ==> Global variable Set (every input block).  This setup is for a Tachometer which has a range of 0-3600 RPM and gives a TTL PWM signal, 0 rpm = 0 hz and 3600 rpm = 14400 Hz on the output of the Counter Input module.  The problem is that I can attach the Digital Meter module to the ouput of the 2 point scale module and see all values from 0-3600 rpm (what I want to see) but the ODBC Output module doesn't seem to want to output the correct value once the frequency gets to around 300rpm (1200 Hz). At speeds greater the 300rpm then the value in Excel starts to decrease towards 0.  I was thinking it could be something to do with the Sample rate and/or Block size so I've tried changing it but if I increase the sample rate to 20 kHz/ch and blocksize = 4000, I run into problems with overruning the buffer.  Any help would be greatly appreciated.

Adam

[Alex A.]

Adam,

It looks like you are using an IOtech board with DASYlab.  You may want to post this question to the IOtech Support and/or to the DASYlab.com forum.  This forum area is normally for DASYlab using National Instrument boards.

[Adam@gmr]

Hi,

I know that it's not an NI board but the problem I believe isn't with the hardware but the software.The way I figure it is, that I'm probably not using the correct module.  The problem occurs when I try to export the data to Excel (using a Global Variable and ODBC output) it just shows up as zero (in the Excel spreadsheet) but on the Digital meter (module) that is connected to the same channel as the Global Variable Set module the correct value is displayed.  The digital meter can calculate that channels frequency and displays it, but the Variable set module is probably sampling to slow and therefore cannot see the frequency value that is on that channel.   If there is a way to get the effect of copying the value displayed on the meter to a global Variable that would solve all my problems.  I have been working on different ways to achieve this but each time I seem to run into little problems, I think I'm just overlooking something simple like checking off a box in one the modules.  Anyways let me know what you think.

Adam 

[Alex A.]

If you need software help with DASYlab, please see my reply above and post to the DASYlab.com forum.