low-level USB control

[Keong Kam]

Hi all,

I'm trying to do some very-low level USB control using Labview. Tasks are:

-Write 1 to output

-Write 0 to output

-Write clock to output.

Very simple tasks (no need to read, just write) , but i need to be able to do this with just a USB cable attached without any device. It will be used to characterize the cable.

The other end of the cable will be terminated appropriately. 

If anyone could give me some information for me to start this, that would be extremely helpful.

[Intaris]

If you want to do something like setting the pins of a RS-232 port without a device attached, this will not work.

USB works fundamentally differently to RS-232.  It is a point-to-point connection.  It doesn't work open ended and you don't have direct access to the signal levels at all.

Look for a cheap I/O device instead and use it for testing.

Shane.