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Message
From: Marc Reinig<mreinig@p...>
Date: Mon Apr 12 05:59:53 CEST 2004
Subject: [usb] 2.0 Hub
Actually I dashed that off too quick.High speed traffic is broadcast to all downstream high speed devices. If
there is a low or full speed device down stream of a high speed hub, it will
be attached as a low or full speed device either directly to a high speed
port, or through a full speed hub, which will be connected as a full speed
device. A high speed hub makes the speed conversion from high to full/low
speed for the full/low speed device. It effectively acts like a host
controller in this case. See 11.14 in the USB spec.
Marc Reinig
System Solutions
-----Original Message-----
From: usb-bounces@o... [mailto:usb-bounces@o...]On
Behalf Of Marc Reinig
Sent: Sunday, April 11, 2004 7:46 PM
To: Discussion list about free,open source USB IP core
Subject: RE: [usb] 2.0 Hub
-----Original Message-----
From: usb-bounces@o... [mailto:usb-bounces@o...]On
Behalf Of M. AbuKhater
Sent: Sunday, April 11, 2004 2:09 PM
To: usb@o...
Subject: [usb] 2.0 Hub
happy easter all;
lets say a USB2.0 hub is connected to a host , with many high-, full-
and low-speed devices connected to it.
> as indicated in the USB system architecture , a full speed packet
> is heared only by full speed devices , same for low- high-speed
devices.
> does this mean that the host sends low and full speed frames to high
speed hub?
No, a high speed host communicates with a high speed device at high
speed. The hub is a high speed device.
> if not how does the hub knows which packet is should go to which
device?
Uh. The device address?
Marc Reinig
System Solutions
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