Thanks a lot, both of you. I am not disappointed in the sense that I got very 
informative advance. Will seek other solution to my need.

Yuyang

-----Original Message-----
From: Greg KH [mailto:gre...@linuxfoundation.org] 
Sent: Thursday, January 24, 2013 2:15 PM
To: Du, Yuyang
Cc: linux-usb@vger.kernel.org
Subject: Re: USB host port acts like a signal generator

On Thu, Jan 24, 2013 at 02:44:44AM +0000, Du, Yuyang wrote:
> Hi,
> 
> My intent is really special, I don't know whether I missed something, 
> but all the articles about writing a USB driver do not address my 
> need.
> 
> I want to use the USB port on the host as a signal generator to drive 
> a USB cable (the two data lines) connected to another device's USB 
> connector. The generator just needs to output 1 or 0 (high or low
> signal) as controlled by a user space program.

That is impossible to do, sorry.  Please read the USB specification
(usb.org) if you are curious as to why this is.

sorry,

greg k-h
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to