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<p>Dave,</p>
<p>Thank you for your reply, which I found both enlightening and
informative. This will also help me explain to others.<br>
</p>
<div class="moz-cite-prefix">On 15/12/2023 17:04, Dave Mielke wrote:<br>
</div>
<blockquote type="cite"
cite="mid:ZXyHIj1FtYJSiDah@beta.private.mielke.cc">
<pre>Disabling the brltty service doesn't prevent it from being automatically
started by a USB udev rule. If you really don't want a Systemd unit to
start then you need to systemctl mask it.</pre>
</blockquote>
<p>I haven't heard of masking a service. To me disabled, means
disabled, i.e no longer active or able to affect the system.
However, having read up on it I see it is a 'stronger' version of
disable. Thank you for pointing that out.<br>
</p>
<blockquote type="cite"
cite="mid:ZXyHIj1FtYJSiDah@beta.private.mielke.cc">
<pre>I hope it's okay for me to
point out that Arduino and friends are just as much to blame as brltty
is. Brltty's problem is that some braille device manufacturers don't
bother customizing their USB vendor and product IDs. Yes, they should do
it. Also, however, so should Arduino and friends be doing exactly the
same thing. There'll always be such conflicts as long as whomever
doesn't stop using generic vendor/product IDs.</pre>
</blockquote>
<p>I am wanting to better understand so its no problem at all. As
far as I know, Arduino does customize its vendor and product IDs.
Genuine boards should be appropriately identified. The problem is
that there are a multitude of clone boards around, mostly from Far
East sources which use generic UART chips and generic IDs. There
are also boards from Adafruit, Sparkfun, STM and others. Not sure
how good they are at customizing their product IDs. There are also
many products from other vendors that have generic chips so I
guess this is always going to be a problem. I had imagined that
there ought to be some way of managing access to devices in udev
or by detecting known Braille devices, but with all those devices
with generic IDs about I can now see that this is not so
straightforward.</p>
<blockquote type="cite"
cite="mid:ZXyHIj1FtYJSiDah@beta.private.mielke.cc">
<pre>Can you suggest a way to
design it that way? Since you expect it to be that way, you must have
some idea regarding how to do it that way. A braille user would be
unable to make such a choice without first being able to read his/her
screen, which means, yes, that his/her braille deivce must already be
working. Let's call it one of those "catch 22" situations.</pre>
</blockquote>
<p>You make a good point here which I failed to appreciate. I would
not imagine Braille user being able to install a Linux system for
various reasons, for example not being able to see the BIOS
messages or knowing when the system has actually finished booting,
but if having brltty built into the distro makes that possible,
then I absolutely support that. I had also imagined that if a
Braille user can open, read and edit a document, that they ought
to be able to respond to a prompt, but how could they do so if the
software that enables this is not yet in place? It makes sense to
have it already right there, in the distro. I guess everyone else
just needs to be aware of it and learn how to disable it
appropriately when its not needed.<br>
</p>
<blockquote type="cite"
cite="mid:ZXyHIj1FtYJSiDah@beta.private.mielke.cc">
<pre>If it's earlier than 6.5 then your distribution is too old. As of
brltty-6.5, we split our USB rules into two - generic and customized.
So, all you really need to do is to ensure that you're at least at
brltty-6.5 and then to uninstall the generic USB rules package.</pre>
</blockquote>
<p>It looks like it is earlier than 6.5. I re-installed brltty from
the repository and ran the brltty --version command as suggested
and it returned version 6.4. My Linux Mint distro is up to date,
but Mint is always behind Ubuntu/Debian in terms of the software
package versions in the repository. I am therefore not surprised.<br>
</p>
<pre class="moz-signature" cols="72">--
John.</pre>
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