[BRLTTY] pac mate question

[Sergei V. Fleytin]

Hello, list!!

I am a brltty user for some time already and soon I am going to own a
Pac mate braille display. One friend of mine has given me his own pac
mate to work for a while and I found it to be a quite usable on
Linux. But I would like to change some key assignments on the
display. Specifically, I would like to make a left and right advance
key to perform an imitation of up / down arrows keys. Please, tell me
how I can do that? I don't mind to modify the sources myself and
recompile brltty, but at the moment I have no idea which part of code
should be changed, since I am not a programmer myself.

Thanks in advance!

Sergei Fleytin.