I guess some more information is in order.


The short answer is that it is tied to +5V on my custom board.


Long story is that the hub device is paired with a power control switch  (TPS2041) for downstream devices. The PWRON and OVRCUR I/O is configured for ganged mode and so all the +5V to downstream devices is switched as a group.  I don’t use the USBH_CPEN signal to do the power switching and instead use the hub and switch combination and I initially had the +5 to the USBH_VBUS attached to that +5V output .  When the hub device did not work (did not assert the PWRON signal outputs) I thought maybe it needed to have that +5V in place to communicate with the hub so I white wired it so that USBH_VBUS always has +5V.


Eric Crossley

From: Keane, Ben (STRX) [via Gumstix] [mailto:[hidden email]]
Sent: Tuesday, December 18, 2012 6:49 PM
To: Crossley, J. Eric
Subject: Re: Embedded USB hub



What have you done with USBH_VBUS (Pin 32 on the J4 connector - if you copied something like the chestnut43 board) line on your custom control board? I believe this needs to be pulled high to 5V so the gumstix knows there is something connected downstream (like your hub).


> -----Original Message-----
> From: Eric Crossley [mailto:[hidden email]]
> Sent: Wednesday, 19 December 2012 8:47 AM
> To: [hidden email]
> Subject: [Gumstix-users] Embedded USB hub
> I am trying to use a TI TUSB2046 USB hub device on a custom expansion
> board
> to provide extra USB ports to an Overo gumstix board.    It is not working.
> Removed the gumstix board from the expansion board and tacked on a cut
> USB cable and connected to computer USB port (without connecting 5V
> power since expansion board has its own power).  This worked and saw USB
> devices on downstream side of the hub pop-up.  What is the difference
> between the gumstix implementation of a USB host and the computer's
> implementation?
> --
> View this message in context: click here.

View this message in context: RE: Embedded USB hub
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