I have modified the 2.x drivers for the USB Powerlinc
(I have an 1132U) to add limited support for extended
code commands (ext code 1 - for data /control; NOT
extended data).
The changes allow the user to send an extended command directly to a unit address:
$ echo EXT 3F31 > /dev/x10/a1
where 3f is the data byte, 3 is the command type, and
1 is the extended command itself. The data format is
spelled out at ftp://ftp.x10.com/pub/manuals/xtc798.doc. The command above for example, means "Turn on immediate at 100%
brightness".
I also implemented a decoder for extended code
responses. Given the way the WISH drivers currently work, I have no idea how to report that status back to user mode applications - it just generates some prints to /var/log/messages.
Tared patch files.