[mythtv-users] Solution for using lirc-enabled remote with xmame.

[Truls A. Tangstad]

This might be slightly off-topic, but since I use my myth-box for also
running mame through mythgame, I thought the info might be of interest
to some subscribers.  Another reason for me posting this is that I had
a very hard time finding information on the web concerning xmame and
remote controls, except messages about irxevent not working, so I hope
this helps someone to have an easier time of making it work than I
had.

I have a silent-running myth-box in my living room, connected to my TV
and network. Attached are a few joypads, a remote receiver and a
keyboard. I'm trying to get rid of needing the keyboard alltogether,
and at the moment xmame was the primary showstopper.

I have a hauppage-250 remote control and have it set up with lirc. I
was initially hoping to use irxevent (part of lirc) to send keypresses
to xmame, but for some reason xmame doesn't respond to the events at
all.

The solution was using the X-extension library XTest through a perl[1] or
python[2] binding. I've only so far tested the python-binding, but it
is based directly on the perl source code. The python-binding seem to
have been created primarily to use an Ericsson phone as a remote, but
the keycontrol module[3] is useful for alot of other stuff (most
importantly xmame).

After compiling the pythoncode and moving the resulting keycontrol.so
shared library to a directory in your python-path, you can use the
binding in any python script like this:

import keycontrol
keycontrol.tapkey('k') # send k to desktop

The bindings use XTestFakeKeyEvent to send a keypress as if it came
from the keyboard itself, and works great with xmame.

To use it with a remote just use irexec (man irexec for more
instructions) which is a part of lirc, and for given keypresses make
it call the python-script (or perl-script) which presses the key.

Example pythonscript presskey.py:
#!/usr/bin/python
# presskey.py
import keycontrol
import sys
for key in sys.argv:
    # assume each argument is the name of a key and press it
    keycontrol.tapkey(key)

Set the script executable, place it in your path, and you can add
'presskey.py k' as a command in .lircrc for irexec to send the
keypress 'k' to the desktop when a certain remotecontrol button is
pressed. Many mamegames require you to press OK when starting, some of
which can be suppressed by using -skip_gameinfo and -skip_disclaimer.
To skip such a screen with the remote, one now only has to configure
irexec to run 'presskey.py o k' when hitting a given button on the
remote.

It might be useful to only enable irexec when xmame starts, then
disable it afterwards, which can be done by creating an xmame-wrapper
script doing just that. Place all your irexec-settings in
~/.xmame-lircrc, create the following script xmame-wrapper.sh, set it
executable and set it as the xmame-executable in the frontend setup of
mythtv:

#!/bin/sh
# xmame-wrapper.sh
irexec ~/.xmame-lircrc &
xmame.x11 $@
killall irexec

One problem I haven't solved yet is pressing keys with modifiers. The
keycontrol.tapkey-function simulates pressing a key and releasing it
immediately, so doing stuff like shift-F9 mapped to one remote button
isn't possible without a slight rewrite of the module.

If someone is interested in examples of .lircrc-files for this use,
just reply to this list, and I can post mine as I get it polished.
If there's any interest, I might post some instruction on a website
with links to examples.

BTW: An alternative way of using the hauppauge remote (and probably
other remotes) is through the ir-kbd-i2c kernel module which makes the
remote act as an input device just like the keyboard. Lirc can be made
to work against the event device (/dev/input/event5 or similar) while
the remote can send keypresses to any program. This might work with
xmame, but I had a big problem with using the kernel module and that
was very sluggish response when pressing keys. Doing stuff like
volume adjustment required repeatedly pressing the buttons, even
though the repeat-value was set low in .lircrc. On the other hand it
might just have been me setting stuff up wrong. Feel free to try it
out as a alternative. YMMV.

Disclaimer: I haven't tested these scripts, the only thing I've tested
is the keycontrol-module. The scripts mentioned are just pointers to
possibilites of what can be done. Feel free to comment on mistakes or
better ways to do things. I am not the author of any of the programs
or bindings mentioned. And no... this posting was not intended to be
this long... *sigh*

[1] - http://sourceforge.net/projects/x11guitest
[2] - http://www.hackdiary.com/archives/000037.html
[3] - http://www.hackdiary.com/src/blueremote-1.0.tar.gz
-- 
Truls A. Tangstad - kerfue+mythtv-users at herocamp.org