[BRLTTY] HumanWare Brailliant, connection issues?

[Mario Lang]

Kazunori Minatani <minatani at debian.or.jp> writes:

>  Hi, Mario.
>
>> Date: Fri, 05 Jul 2013 14:53:52 +0200
>> From: Mario Lang <mlang at delysid.org>
>> Subject: Re: [BRLTTY] HumanWare Brailliant, connection issues?
>>
>> Kazunori Minatani <minatani at debian.or.jp> writes:
>> 
>> > I Had tested Brailliant BI40 (firmware version was 1.7) with Debian Wheezy's BRLTTY (4.4 r5477).
>> > With USB connection, it was recognized as a USB <-> serial converter.
>> > Then executing BRLTTY with -d serial:ttyACM0, it was acted as a BRLTTY's braille display.
>> > My experience may be a different kind of problem.
>> 
>> Did it actually work for you?
>> If not, you can try "-d usb:", BRLTTY should be able to talk to the
>> HumanWare chip directly via USB.
>
> Unfortunately, I had only tested Brailliant shortly, and it is not here now.
> Of course, I had also executed BRLTTY using Debian's ordinary way "/etc/init.d/brltty start".
> I think "/etc/init.d/brltty start" is functioned as an equivalent of "-d usb:".

The default configuration of the Debian package is to try and search the
USB bus for known devices, so if you have not substantially changed
/etc/brltty.conf, /etc/init.d/brltty start does indeed yield the same
result as invoking BRLTTY with the "-d usb:" option.

> In spite of "idVendor=1c71, idProduct=c005" is recorded in BRLTTY's Humanware driver source as its id,
> Linux kernel recognizes a Brailliant as an USB modem then load cdc_acm.ko module.

That is to be expected, because the HumanWare Brailliant displays indeed
usees a USB serial chip that behaves like a cdc_acm modem.  BRLTTY will
claim the relevant device once you tell it to search for it, so the
loaded kernel modules are basically irrelevant, since "user space" is
telling the kernel to give up control about this particular USB device.

-- 
CYa,
  ⡍⠁⠗⠊⠕