Petrel 2 Download

Jef Driesen jef at
Wed May 20 03:09:03 PDT 2015

On 19-05-15 17:57, Anton Lundin wrote:
> Just another wild guess is to test another rfcomm channel? You can take
> a look at what the device says with sdptool browse.

This is an interesting question. The bluetooth rfcomm channel is very similar to 
a tcip/ip port. If I remember correct, the available range for the channels is 
from 1 to 31. But I'm not sure where the channel number gets chosen: the remote 
device (e.g. like tcp/ip ports), or somehow negotiated by the bluetooth stack 
and thus variable.

The rfcomm tool uses channel 1 by default, unless the channel number is 
explicitly set. In my bluetooth prototype, I also hardcoded channel 1. So if for 
whatever reason the channel number is different, then that probably explains all 
those connection refused errors!


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