Sorry I was not realy clear in the first post.
I'm trying to send a vendor specific command from my host application to the FX3 device.
You will need to add code to your firmware to catch the vendor request. See post http://www.cypress.com/?app=forum&id=167&rID=53345 for some example code
You will have to change the vendor request in this example from 0xB1 to 0x07 - (your request) and to update the size of the endpoint buffer in the example to 128.