Sunday, January 3, 2010

Understanding Firewire

I’d like to kick off 2010 - Happy New Year everyone! - by sharing with you one of the most interesting and informative papers I have ever come across on the subject of “Using Firewire for Machine Vision.”

This is a twenty-four page paper buried away in the “
VisionPro Support” area of Cognex’s web site that goes into great detail in explaining the pros and cons of using 1394. For example, did you know that one way to address the 1394(a) speed limitation is to use two 1394 cards in your PC, one per camera? Seems obvious, but I had never thought of doing that.

Another approach that Cognex offer to managing multiple camera Firewire bandwidth issues is to set the proportion of the bandwidth that each camera can use. If you have a set up where you want to allocate 50% of the bandwidth to one camera and leave two others to split the other 50% 50:50, then you can do it with VisionPro.

Cognex will make you register before they’ll give you access to the documentation, but as I said about Keyence doing the same, that seems like a reasonable exchange. I’m just a little surprised that Cognex don’t make this information more widely known because it actually does a great job of promoting their products.

1 comment:

Anonymous said...

You can add more bandwidth with any interface type by just adding hardware.

There are dedicated cards available for Camlink and GigE also:

http://www.silicon-software.com/microenable4.html