[BRLTTY] Are USB product ids hard coded in BRLTTY

[Nicolas Pitre]

On Fri, 8 Jun 2007, Elias Oltmanns wrote:

> Hi all,
> 
> because there is no serial port on my computer, I hlve to connect my
> old Handytech Modular 40 by means of a prolific usb-serial converter.
> Sadly, brltty doesn't find the braille device searching the usb bus,
> regardless whether pl2303 (the kernel module for teh prolific
> usb-serial converter) is loaded or not. Loading pl2303 and accessing
> the braille device thgough the serial interface /dev/ttyUSB?, however,
> works perfectly well.

BRLTTY only looks for true USB braille displays directly.  If you use a 
USB-to-serial adaptor (of which there are plenty different ones) then it 
is really a serial braille display to BRLTTY.

> The reason why I'd like to use the usb interface
> rather than the serial interface is that the braille device is not
> guaranteed to show up as ttyUSB0 all the time due to race conditions
> and similar issues. It works most of the time and if there really is
> no way to use the usb interface of brltty in this case, a bit of
> slightly more sophisticated udev scripting will very likely do the
> job. Still, I thought I'd ask first.

The udev approach is certainly the sane thing to do in that case.


Nicolas