Braille display and serial console

Tony Baechler tony at
Wed Sep 30 09:22:29 UTC 2015

Hi all,

I have a question about using a Braille display with a serial console.  I 
don't have access to a Braille display, so I have no way to determine this. 
  Any help and guidance you can offer would be greatfully received.

If you boot a machine with the serial console enabled and you have a Braille 
display on the serial port which is configured as the serial console, is 
there a conflict?  To make it more simple, if a boot message is sent out the 
serial port as plain text with the display connected, does that cause a 
problem for the display?

I'm asking because I'm working on a live CD and I would like to enable the 
serial console.  For speech users who still have a serial synthesizer, it's 
great because you hear the boot message.  However, I don't want to cause a 
problem for people using a Braille display.  This would be as soon as the CD 
starts to boot at the boot loader level, long before brltty would get 
loaded.  Ideally, it would be nice if the boot text would show up on the 
Braille display, but knowing how sensitive devices are to random characters 
sent out the serial port, I don't want to create a conflict.  For example, 
the default Talking Arch CD runs brltty at boot and I get random characters 
from my DECtalk Express, but it locks up my synthesizer and I have to power 
it off and on to get speech back.  I want to prevent something similar for 
users of Braille.

Again, I can't currently test this so your help would be very appreciated. 
I can send the link for the test CD image if you want to try it, but it is 
currently not booting correctly.

Tony Baechler, founder, Baechler Access Technology Services
Putting accessibility at the forefront of technology
mailto:bats at
Phone: 1-619-746-8310   Fax: 1-619-449-9898

More information about the Blinux-list mailing list