How do I do HS data acq with pci6110, winxp, >2GHz pc, 512MB RAM, LabVIEW6.1: What Labview techniqes maximize data handling speed?

[flargy_g]

I am using a pci6110 High Speed DAQ board (capable of 5MS/s on 4 chan simultaneously). I have labview6.1, winxp, >2GHz pc, 512MB RAM. I want to collect bursts of data, externally digitally triggered at a rate of 5Hz for a duration of 185 msec per trigger using an internal clock speed of 4MScans/sec on all 4 channels. How do I handle the buffering (sizes, reading) and anything else pertinent, so that I can acquire for every trigger and write the data to HD. I would like to be able to collect & write up to 64 acquisitions consecutively without missing a trigger.

I can get the system to collect data at that rate, but each burst takes abou
t 1sec to collect and write; hence I miss about 4 of 5 triggers.

I am relatively new at Labview (user for about 6-8mo) and have never done high speed acquisition before.

[Ben]

Check out the examples that ship with LV.

You will be looking for the "continous double buffered" examples.

Using the hardware you mentioned, you should be able accomplish your task.

You will want to do continuous acquistion from all of the channels for the entire test. The simplest approach would just spool the data to file and then use post proccessing to find the triggers you are after.

Rather than using hardware triggering (wired to a discrete pin) do the triggering in software durring the post proccessing.

Ben

[Sastry V.]

Hello,

Thanks for the nice answer Ben. Also, I am providing the names of two places where you will be finding the examples:

1. LabVIEW Help >> Find Examples >> Hardware Input Output >> DAQ >> Analog Input.


2. Analog Input Example on NI Developer Zone

Please feel free to let us know if you have any questions.

Sincerely,
Sastry V
Applications Engineer
National Instruments.

[flargy_g]

Thanks for the answer. This has been helpful.

[flargy_g]

Thanks for your answer. I would not have looked at these. This has been helpful

[Fabien Palencia]

Hello

I'm a french user of a 6110 in similar system

@ 5 Hz , period is 200 ms, and you need to acquire 185 ms and 15ms for
transfert is not enought.
You are a Big Problem 4*4*2*1Mo/s=32Mo/s during 64/5=13s and you need to
make a file 13*32Mo is 416Mo.
You need to have :
- A big and very fast hardDisk, a IDE raid with 2 disk of 100Go is a
minimum

You need to make :
- a big buffer 2s min per chan for secure
- 1 binary file for 64 top (create a file is very long for you>15ms)
- a continously acquisition synchro to start with you 5Hz.
|->- a reading of your 185ms to write in disk
| - a reading of the 15 ms and in a parallele while loop a flush of the
file to really write
|-- - make 64 time this loop

Good luck

if my planning is not full i
can make a vi for this example



Fabien Palencia
Ingénieur
ICMCB CNRS
87, Av du Dr Al. Schweitzer
33608 Pessac
Email : Palencia@icmcb.u-bordeaux.fr
Tel : +33 (0) 5 56 84 26 76
Fax: +33 (0) 5 56 84 27 61