Return-Path: Date: Fri, 21 Dec 2007 14:49:52 +0100 (CET) From: Peter Wippich To: BlueZ development In-Reply-To: <1198244391.8050.285.camel@aeonflux> Message-ID: References: <009b01c8432a$f2b9a800$0200a8c0@jester> <000801c84343$f6efce40$0200a8c0@jester> <003101c843ba$5d611280$0200a8c0@jester> <1198244391.8050.285.camel@aeonflux> MIME-Version: 1.0 Subject: Re: [Bluez-devel] Creating a connection : Error: Command Disallowed Reply-To: BlueZ development List-Id: BlueZ development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Sender: bluez-devel-bounces@lists.sourceforge.net Errors-To: bluez-devel-bounces@lists.sourceforge.net Hi Marcel, Hi Olivier, On Fri, 21 Dec 2007, Marcel Holtmann wrote: > Hi Olivier, > > > I have tried parallel connection requests with 2 types of dongles : > > - Cambridge Silicon Radio (CSR) one is successful for the first connection, > > and, as Peter said, returns "Command Disallowed" for next ones (and there > > are automatic retries) > > - Integrated System Solution Corp. one allows all connection requests (no > > more "Command Disallowed") > > not seeing the "Command Disallowed" doesn't meant the connection request > is not queued. It is impossible to have two (or more) baseband pages at > the same time. You only have one radio in the chip. Once that is busy > with a connection attempt, then everything else has to wait. So if the > host stack queues these connection attempts or the link manager inside > the Bluetooth chip makes no real difference. > Marcel is perfectly right. The Radio/Baseband is a shared resource and busy when setting up a conection. So all connection attempts must be serialized. The only way to speed up the process may be to do an inquiry first, so you know the clock offsets for the different devices. Knowing the clock offset usualy makes connection setup a lot faster. If I remember right BlueZ caches the clock offsets and uses them in a connection request if available. However, the connection setups still need to be serialized (either inside the Bluetooth chip or inside the stack). Ciao, Peter | Peter Wippich Voice: +49 30 46776411 | | G&W Instruments GmbH fax: +49 30 46776419 | | Gustav-Meyer-Allee 25, Geb. 12 Email: pewi@gw-instruments.de | | D-13355 Berlin / Germany | ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Bluez-devel mailing list Bluez-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bluez-devel