Date: Tue, 20 Jul 2010 19:03:37 +0200 From: Bernd Walter <ticso@cicely7.cicely.de> To: Greg Ansley <gja@ansley.com> Cc: "freebsd-arm@FreeBSD.org" <freebsd-arm@freebsd.org>, Bernd Walter <ticso@cicely7.cicely.de>, ticso@cicely.de Subject: Re: AT91RM9200: USB broken? No! Message-ID: <20100720170337.GB28908@cicely7.cicely.de> In-Reply-To: <4C45C2AF.9030608@ansley.com> References: <4C4590E5.1020407@ansley.com> <201007201405.43686.hselasky@c2i.net> <4C45A47A.8070403@ansley.com> <20100720135858.GA28908@cicely7.cicely.de> <4C45C2AF.9030608@ansley.com>
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On Tue, Jul 20, 2010 at 11:37:19AM -0400, Greg Ansley wrote: > It's a QFP so the errors are OK. > > Turned out to be a bad solder joint on pin 1 of the USB connector > (power). Connector on this card is not very mechanically stable with the > mounting posts going into huge worthless holes. :-( That makes sense. A device pulls up one of the data line up to 3.3V with a 1.5k Ohm resistor to show presense. A bus powered device however can't do this without having power and a self powered device isn't allowd to supply current into data wires without sensing the 5V, although many self powered devices violate this rule. So in fact a few self powered devices might function without 5V from USB, although they are not allowed to. > Error messages were just a red herring, after not having seen them for > weeks while working on the SAM9G20. > > Greg > > On 7/20/10 9:58 AM, Bernd Walter wrote: > >So it looks like your device isn't noticed as being connected at all, > >which is a bit strange because your error messages clearly show that > >it got the faulty device connected from the secondary port. > > > > > _______________________________________________ > freebsd-arm@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-arm > To unsubscribe, send any mail to "freebsd-arm-unsubscribe@freebsd.org" -- B.Walter <bernd@bwct.de> http://www.bwct.de Modbus/TCP Ethernet I/O Baugruppen, ARM basierte FreeBSD Rechner uvm.
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