[BRLTTY] Brailliant Bi40X and bluetooth

[Isabel Ruffell]

Hi David,

Thanks for getting back to me.

On Mon, May 05, 2025 at 01:57:32PM -0400, Dave Mielke wrote:
> [quoted lines by Isabel Ruffell on 2025/05/05 at 13:58 +0100]
> 
> >I have been using a HumanWare Brailliant BI 40X with a laptop running Debian Stable for a couple of years, and the connection via usb is reasonable. But I would like to get the bluetooth connection working, and have never managed to do so. Can this list help?
> 
> We can certainly try.
> 
> >This is where I have reached:
> >
> >1. I can see, pair and trust the device.
> >2. I can induce the unit to think that it has connected with the laptop, and save the connection
> 
> What do you mean? Do you mean that you did an rfcomm connect? When trying to figure out a problem it helps to know the details.

Sorry. To be more precise (i hope).

1, In the Terminal application, I go to "Add Bluetooth Device", and it gives the details to identify and pair the device on the computer
2. After pairing the device on the computer (I have tried this with bluetoothctl, blueman-manager, and through GNOME settings at different times) the device appears in the list of "Connected Devices" on the BI 40X [that is, both in the Terminal application and in the Options / Bluetooth menu.
3a. If I initiate a connection from the computer (from any of those programs), it goes into the connect/disconnect cycle. This through  some uninformative dialog boxes or similar.
3b: "Brailliant BI40X Disconnected". If I initiate the connection from the BI 40X, by selecting the connection there, it simply says "Braille Display". 

As a side-effect, thelast does also disrupt the speech on both the BI40X and the computer (via orca).
the computer.

> 
> >3. I can initiate a connection from the laptop.
> 
> By doing what?
> 
> >At this point it goes into a cycle of disconnecting and connecting.
> 
> What's reporting this, and are you able to quote the exact messages?

[See above]
 
> >Investigation of logs reveals two possibly interesting errors
> >
> >a) RFCOMM connect error (111): connection refused
> 
> Yes, I'd expect this error because the BI40X doesn't support a Bluetooth serial connection. It only supports Bluetooth HID.
OK, That eliminates one thing then.

> 
> >b) hidOpenBluetoothDevice error (38): function not implemented  
> 
> To me, this imlies that brltty, when built, wasn't configured to include HID support. Did you build it for yourself or is it provided by the distribution?
It is the distribution's package. I have not compiled anything. 

But, just to reiterate: it works via usb, and I could get the BrailleNote Touch working via bluetooth. So maybe it is something more specific than a global lack of hid support? 

 
> >I know the pairing process is different for this compared with (e.g.) the earlier BrailleNote Touch (c.2018) which I also have and which works. 
> 
> It shouldn't be. What do you believe that difference to be?

It may be no more than that this unit does not do anything with a PIN as the older unit did. The pairing with the BI40X is less involved, although I don't know how far that affects anything under the hood. (I remember this being flagged in the docs but that was a while ago.)

Thanks for your help so far!

Isabel


-- 
Isabel A. Ruffell
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