Analog sampling rate via USB bluetooth xbee.

[mknix]

Hi everyone,

I'am new in this group, I've found here a lot of precious informations, so first of all thanks to all the contributors, and special metion for NathanB

I've successfully interfaced my arduino with LV, then managed to read a signal comming from custom strain gauge bridge, amplified by an INA125P.

I tried both USB and Blutooth communication, and found that the sampling rate is damn low with bluetooth, even for a simple while loop withe only one analog input....

I guess this is an HW limitation, but in case I ask if you have any idea to improve this?

Any chance to have something better with Xbee?

what kind of sampling rate can we expect wirelessly in optimal condition ?

My set up is the following :

Arduino UNO R3 + itead studio blutooth shield v2.2, (115200 baudrate).

LV2009

win XP

Many thanks in advance !

antoine

[Nathan_B.]

Serial communication will often be the slowest part of the whole setup.  You would want to use the continuous analog sampling available in LIFA v2.1.1.69.  I'm not sure how well it works as I've never actually used it (or v2.1.1.69).

[mknix]

Yes, serial is the bottleneck, but with USB, I was surprised in a good way, it was more than enough for my application.

The disapointement came when I moved to wireless communication...

I've tried before the continuous sampling .vi over USB,  I didn't find it this usefull, and it works with only one input at a time. But will try again with bluetooth, and see if I can get some improvement, will post here the result.

thanks for the tip.

antoine

[mknix]

Tried the continuous sampling vi, and it indeed helps, thanks again.

The main limitation is that while running this mode, you can't execute other LIFA commands.

But at least that will do for what I need