From: Gideon Zweijtzer (gideonz_at_dds.nl)
Date: 2003-07-11 09:02:14
> USB2.0 is a fraud in my opinion. USB 1.0 is the slow usb
> (dont remember, 1.5Mbps?), usb 1.2 is 12Mbps, and usb 2.0 was
> originally 480Mbps.
>
> Customers were demanding motherboards with usb 2.0 installed
> on them, so instead of making boards with EHCI (480Mbps)
> controlloers, they completey redid the naming scheme. USB2.0
> no longer indicates EHCI. Its name was raped and applied to
> the USB1.2 12Mbps port.
Hi David,
I am not sure to which extent it is a fraud, but I have noticed
something weird going on with USB 2.0 as well. However, IMHO USB 2.0
devices have just more capabilities, of which the 480 Mbps datarate is
only one. It includes other capabilities such as negociation about which
of the two ports is going to be upstream and which downstream (host vs
device), which is called USB On The Go. This is used in many imagaging
devices such as digital cameras which can be slave to a PC, but master
to a printer. I believe that a device is not obligated to support all
new 2.0 features as long as it is able to play the negociation game with
another USB 2.0 device.
Offering a USB2.0 capable host that does not support 480 Mbit/s is at
least something like 'the cat in the sack'; misleading indeed.
Gideon
PS.. USB 1.1 was 12 Mbps.
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