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From: Andrew Jackson on 31 Mar 2010 03:36
>> Now I'm going to plug in a hub, which has got to do 12 Mb/s. Their QP1
>> command should report a hub on port 1 according to the docs. However, I
>> havent had a USB Flash work through a hub, so I'm very dubious... Surely,
>> if it doesn't work with hubs then it can't claimto be USB?

Since the chip is operating as an embedded USB host, it may be that they
only support the USB host's root port. That said, its not that
difficult to support a hub although there is then a certain amount of
complexity in the device management.

> I have now had a response via a friend. So it looks like they are ignoring
> me specifically. I haven't had chance to check out the reply, but it boils
> down to "put a resistor here". Of course most of the schematics don't have
> that, and one that does is discussed in the Vinc II docs where they say the
> resistor(s) aren't needed even for the VNC1L.

The Vinculum data sheets look a little light on detail for the USB
interface (perhaps on the basis that "it just works"). Is this
(missing) resistor a pull up(/down) on one of the USB lines?

Andrew
From: Peter Dickerson on 2 Apr 2010 08:26
"Andrew Jackson" <alj(a)nospam.com> wrote in message
news:gt-dnb9Aw8seZi_WnZ2dnUVZ8nednZ2d(a)eclipse.net.uk...
>>> Now I'm going to plug in a hub, which has got to do 12 Mb/s. Their QP1
>>> command should report a hub on port 1 according to the docs. However, I
>>> havent had a USB Flash work through a hub, so I'm very dubious...
>>> Surely,
>>> if it doesn't work with hubs then it can't claimto be USB?
>
> Since the chip is operating as an embedded USB host, it may be that they
> only support the USB host's root port. That said, its not that difficult
> to support a hub although there is then a certain amount of complexity in
> the device management.
>
>> I have now had a response via a friend. So it looks like they are
>> ignoring
>> me specifically. I haven't had chance to check out the reply, but it
>> boils
>> down to "put a resistor here". Of course most of the schematics don't
>> have
>> that, and one that does is discussed in the Vinc II docs where they say
>> the
>> resistor(s) aren't needed even for the VNC1L.
>
> The Vinculum data sheets look a little light on detail for the USB
> interface (perhaps on the basis that "it just works"). Is this (missing)
> resistor a pull up(/down) on one of the USB lines?

Sorry,
My connection has been dead for a few days.

The resistor is a pull-up on an unused signal (DATAREQ#). The resistors for
USB are internal, but I don't think a host needs pull-ups/downs like
USB-devices do.

The pull-up did help but I still have some unhelpful symptoms. If I plug a
keyboard, printer or flash into the port then it reports it (the keyboard is
a slow device). If I use a hub it doesn't report the connection but I do see
the hub and flash. I don't see a mouse whatever. The flash is identified
though a hub on port 2 but not at the file system level - it is seen without
the hub. I've yet to get any data to/from a keyboard or printer, which are
the things I need to do urgently.

Peter


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