Execution speed onboard programs

[JaviHH]

Hi all

I am tying store the value of analog input channels of PCI-7352 on buffer, from onboard program.

The program run fine, but I don´t know how measure the total acquisition time in the program.

In an example in LabView ( adc-gpbuffer.vi ), use 'flex_load_delay' function to establish an interval in

the acquisition. But the real interval between readings not is calculated.

Another question, How I can know the execution speed of onboard program ?.  The documentation does not

show information.

         Thank´s

         Javier

[Jochen]

Javier,

there is no easy way to measure the execution timing of onboard programs. One thing that you could do is to toggle a digital line in your onboard program and measure the timing with an oscilloscope.
Please be aware that the timing of onboard programs doesn't work deterministicallly as onboard programs don't run with time critical priority on the board's CPU so you will probably see a fair amount of jitter.

The main purpose of the analog inputs on the 7352 is analog feedback. You can use them for single point measurements, too but if you need to acquire data with an accurate timing you better should use an additional M-Series board like the PCI-6220 which provide a much better measurement and timing accuracy and as true measurement devices they provide a whole set of additional useful features.

Best regards,

Jochen Klier
National Instruments Germany

[JaviHH]

Hi Jochen,

thank's for yor answer. The reason of use analog acquisition in PCI-7352 is that I really don´t need high data acquisition rates ( 500 Hz aprox. ).

The use of a auxiliar DAQ board no seems justified, and like me the idea of onboard program registered data in buffer  ( ADC1...ADC4 + AXIS1 position ). I´m using a VisualBasic 6 program for the application, and I can't change the development tool.

Registering single points form the VB program, I'm get 100 Hz acquisition speed, but is not sufficient. I'm thankful anything idea.

     Javier

[Jochen]

100 Hz is the analog data acquisition speed that you can expect from a PCI-7352. Unfortunately there is no way to read the ADCs faster than that.

Jochen

[JaviHH]

AAAAAGGGGG !!!

Well ..

OK Jochen, thank´s for all

      Javier