Return-Path: From: mindentropy To: Brian Gix Cc: linux-bluetooth@vger.kernel.org Subject: Re: Re: Regarding setting baud rate for RFCOMM. Date: Fri, 09 Dec 2011 02:39:59 +0530 Message-ID: <15405272.3etRtz984e@terranet> In-Reply-To: <4EE1213F.1090303@codeaurora.org> References: <2121084.BaNgyA18vB@terranet> <4EE1213F.1090303@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Sender: linux-bluetooth-owner@vger.kernel.org List-ID: On Thursday 08 Dec 2011 12:42:39 PM Brian Gix wrote: > Hi mindentropy, > > On 12/8/2011 12:12 PM, mindentropy wrote: > > How can I set the baud rate and other tty settings for RFCOMM for > > data > > > > sending? The receiving application is a windows application which reads > > at 115200 baud rate via virtual comm port. > > Baud rate does not really apply to RFCOMM in bluetooth. Baud rate refers > to how fast the level shifters on a piece of UART hardware (perhaps > RS232) transition between one bit to the next, while RFCOMM simply grabs > data (in the case of bluez, through a pipe or socket) and sends it over > the BT link at whatever rate the underlying ACL connection currently > supports, which constantly is changing to based on environmental conditions. > > The RFCOMM transport in BT is intended to be a simplified way to migrate > an existing UART based application to bluetooth. > > But in fact, if you were to create a UART abstraction on top of RFCOMM > which did accept baud rate as a parameter, it would not matter if you > set the BAUD to 300, 115200, or 921600 -- The data would flow at a rate > that you would not be able to directly control. Other than that, it > would generally mimic "classic" RS-232. In other words, you shouldn't > need to do anything to your Windows App, as long as it is currently able > to send and receive data via the virtual comm port. I am slightly confused. I am sending the data in linux according to http://people.csail.mit.edu/albert/bluez-intro/x502.html In the windows side I open up hyperterminal and connect on the virtual comm port @ 115200 baud rate. I don't get any data though. What am I doing wrong?