Re: [Gumstix-users] USB OTG port not supplying enough power? Or am I using the wrong cable?

[Alexander T. <ale...@es...>]

I only have experience with the Tobi board but if all OTG ports behave
the same, then the OTG port will only work as host if the correct
cable is plugged in while the Overo is being booted up. The cable must
short the ‘id’ pin of the OTG port to ground.



On Wed, Apr 18, 2012 at 10:11 PM, Lou Morda <lmo...@gm...> wrote:
> Hey guys,
>
> Jack and Don suggest that I keep posting on here... hopefully someone can
> answer.
>
> I've got an overo connected thru a stagecoach.  I'm connecting a usb
> peripheral to the usb otg port of the stagecoach.  The usb device is a
> radio.  Sometimes the gumstix connects with the radio, and other times it
> does not.
>
> I've learned the following in the last couple of days.  First, other people
> are having problems with the USB OTG port.
>
> http://gumstix.8.n6.nabble.com/USB-OTG-not-working-as-host-td662224.html
>
> Second, the radio I have needs a 5V signal to let it know that a USB
> connection is present, and it does NOT draw any current.  So, it seems that
> sometimes the gumstix sends the required 5V, and sometimes it does not.
> Third, according to the above post, I'm not using the correct cable.  I've
> got a Standard A USB 2.0 cable coming from the radio, and I've connected
> that to the USB OTG port with a mini B adapter. Fourth, the connection works
> every single time if I put a powered usb hub in between the USB OTG and the
> raido.
>
> Two questions:
>
> Do i HAVE to use a powered usb hub?  I'm pretty sure if I do that may kill
> my project.
>
> If I use the USB mini B to mini A cable on the gumstix website (and also
> talked about in the above mailing list post), will that "work every time"
> without a powered usb hub?  Like, if I use that cable, then will the gumtsix
> know that it is a usb host "every time", and send the required 5V signal to
> the radio?
>
>
> Thanks.
>
> -Louis Morda
>  SAIC Computer Scientist
>
> ------------------------------------------------------------------------------
> Better than sec? Nothing is better than sec when it comes to
> monitoring Big Data applications. Try Boundary one-second
> resolution app monitoring today. Free.
> http://p.sf.net/sfu/Boundary-dev2dev
> _______________________________________________
> gumstix-users mailing list
> gum...@li...
> https://lists.sourceforge.net/lists/listinfo/gumstix-users
>



-- 
Alexander Thomas
Research Engineer

eSATURNUS NV
T +32 16 40 12 82
M +32 477 51 63 62
http://www.esaturnus.com