linux-bluetooth.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Brian Gix <bgix@codeaurora.org>
To: mindentropy <mindentropy@gmail.com>
Cc: linux-bluetooth@vger.kernel.org
Subject: Re: Regarding setting baud rate for RFCOMM.
Date: Thu, 08 Dec 2011 12:42:39 -0800	[thread overview]
Message-ID: <4EE1213F.1090303@codeaurora.org> (raw)
In-Reply-To: <2121084.BaNgyA18vB@terranet>

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.

-- 
Brian Gix
bgix@codeaurora.org
Employee of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum

  reply	other threads:[~2011-12-08 20:42 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-12-08 20:12 Regarding setting baud rate for RFCOMM mindentropy
2011-12-08 20:42 ` Brian Gix [this message]
2011-12-08 21:09   ` mindentropy

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4EE1213F.1090303@codeaurora.org \
    --to=bgix@codeaurora.org \
    --cc=linux-bluetooth@vger.kernel.org \
    --cc=mindentropy@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).