[BRLTTY] Need help remapping display

[S. Massy]

Hello,

This morning, I awoke only to find out that the right side three keys on
my Baum Vario/Brailliant 40 had gone dead during the night. I remember,
upon a similar incident, I remapped my display so that other buttins,
especially the routing keys could take over until the device could be
repaired. That was over four years ago and had meant whacking at the
code to get it to do what I wanted. Now, I see functions are mapped
externally through files in /etc/brltty. How could I assign some routing
key combinations to certain functions? How does one declare specific
RoutingKey combination? What is the meaning of the operator ! , as in
RoutingKey+!RoutingKey?

Thanks.

Cheers,
S.M.
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