how to read data from USB port?

[q-nust]

Thanks guys for your response, but my question remains the same.

First of all if the USB Slip rings are available then why I can't convert my slip rings cable to the USB cable and get the data in Labview.

Secondly Slip rings are sending digital signals so I want to get these digital signals in the LabView.

Third I cannot use the serial port because then I would not get the data in high speed.

Fourth I want to bypass the Digitzer so I can be independent on my project.

[RavensFan]

You still need to define what you are working with.  Do you have a device?  Do you have a link to it?  What the heck is a "USB slip ring"?

Be careful saying digital.  It could have multiple meanings.  The common data acquisition meaning is that a digital input is either On or Off, High or Low.  But the other meaning where you are sending digital data would be sending data on either a serial data bus (or even a parallel data bus) as a series of 1's and 0's matching a particular protocol for timing, start bits, stop bits, parity.

Something that is USB is the latter.  But the assumptions so far is that you want to measure a digital input as in a distinct on and off signal, not a varying voltage level analog signal.

So give some details on what you are trying to do.]

After 22 messages, you owe us that.

[q-nust]

my question was simple but I don't know why you people are making it complicated. 

Forget about it which data is coming just tell me how I can read the data from my own made altered USB cable. The data which is coming is of USB protocol just tell me how I can read the data in LabView. 

I made the USB cable recognized by the Laptop but now how I can communicate with this USB cable. By VISA I am not able to get the driver Installed.

[RavensFan]

It's complicated because you started mentioning slip rings, which may or may not have anything to do with your problem.

It's complicated because you still have failed to tell us what you are trying to communicate with.  All you've mentioned is a "homemade altered USB" cable.

WHAT IS IT CONNECTED TO?

Can you get your device to communicate with LabVIEW if you use a standard commerically manufactured cable?  If you can't do that, then you probably have a driver problem.

If you can get things to work with a real cable, then you know you have that half the problem solved.  Then you can figure out why your homemade cable/slip ring assembly is not working.

[kausreloaded]

I thing these links might help you.....

http://digital.ni.com/public.nsf/allkb/5F30CD20D4D986CC862576CF00748B15

http://digital.ni.com/public.nsf/allkb/ED3790E56FE969F8862575C30076063C?OpenDocument