Return-Path: Message-Id: <200611211021.kALALWc1030513@news01.csr.com> To: BlueZ users In-reply-to: References: <1164101366.28429.22.camel@localhost> Date: Tue, 21 Nov 2006 10:21:32 +0000 From: Peter Stephenson MIME-Version: 1.0 Subject: Re: [Bluez-users] concurrent operations Reply-To: BlueZ users List-Id: BlueZ users List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Sender: bluez-users-bounces@lists.sourceforge.net Errors-To: bluez-users-bounces@lists.sourceforge.net "Mikael Lindqvist" wrote: > And a "page" does that mean a service search? I've seen the term page > in the bluetooth standard but haven't really understood it. What about > several "pages" at the same time, i. e. service search for several > remote devices at the same time? Paging is the period when you're trying to connect to the remote device. This takes variable amounts of time, depending on how frequently the remote device is scanning. Since scanning takes power, most devices only scan occasionally. For a battery powered device, once every 1.28 seconds is typical. Since the scan is short, it's important that the paging device devote the entire radio bandwidth to trying to pick up the remote device. Hence you're stuck with not being able to do anything else at this point. The same argument applies to inquiry (device discovery), although it's intrinsically unreliable --- you're not guaranteed to discover everything. Once connected it's possible to timeslice between different remote devices (although there are more complicated issues to do with network topology lurking). The actual service search takes place when connected, but the chances are the paging process before took longer, so that will dominate the time. pws To access the latest news from CSR copy this link into a web browser: http://www.csr.com/email_sig.php ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Bluez-users mailing list Bluez-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bluez-users