Control Hubs: Bringing It All Together - Smart Home Automation with Linux and Raspberry Pi - page 234

Cosmic
Cosmic is an RF-to-PC gateway that uses Heyu to intercept the X10 signals that have been placed on the power line
by an X10 RF transmitter (such as an HR10 or SS13E) and triggers an arbitrary piece of code. This could be to control
the volume of the currently playing music, skip tracks, or start timers to aid with the cooking. This is probably the
cheapest method of introducing stand-alone wireless control panels to your home.
There are two main issues with this approach. The first is that these devices have no feedback mechanism.
Consequently, you will need to design your interface such that every button causes a noise, speech output, or visual
cue upon each key press. It is your responsibility to ensure that the server processing these commands understands
where the switch is located so that it can make these feedback noise cues in a location where they will be heard.
The second problem concerns X10. Because the controlling messages are X10 signals, they will also control any
lights on the same addresses. Depending on the size of home, you may either have to split your X10 address into two
or utilize two house codes. In the case of the former, you can split the addresses into two sets, with 1-8 to control the
lights, teakettle, and standard appliances as normal, and with 9-16 working as the second set that is not found on
any devices and used solely by Cosmic. There is a switch on most remotes to toggle between these particular address
sets and so is no coincidence that they've been chosen here. Consequently, the button is reappropriated as a home
control/Cosmic control task switcher.

Configuration
Assuming that you have eight available addresses, this gives you 16 workable buttons—on and off for each of the eight.
In case these later change, you can alias them within the /etc/heyu/x10.conf file like this:

ALIAS cosmic1 E9
ALIAS cosmic2 E10
ALIAS cosmic3 E11
ALIAS cosmic4 E12
ALIAS cosmic5 E13
ALIAS cosmic6 E14
ALIAS cosmic7 E15
ALIAS cosmic8 E16

You can configure the heyu daemon, which is always watching the power line, to invoke specific commands whenever
a message for these addresses appears. In its default configuration, Cosmic splits the commands into three groups:

u Media control

u State-based operations

u
The media control ones are global and functional all the time. This is because of their relative importance. They
allow you to increase and decrease the volume, as well as mute/unmute the music, and they provide a way to pause
all the currently playing media. They occupy the top four buttons (two rows) of a standard HR10. The commands they
run all use the abstracted Bearskin commands and are added to x10.conf like this:

State control

SCRIPT cosmic1 on :: /usr/local/minerva/bin/mixer default dec master 10
SCRIPT cosmic1 off :: /usr/local/minerva/bin/mixer default inc master 10
SCRIPT cosmic2 on :: /usr/local/minerva/bin/mixer default toggle
SCRIPT cosmic2 off :: /usr/local/minerva/bin/pmedia default

Remember that these commands will be executed by whichever user invoked heyu engine initially. They must
therefore have appropriate access rights to the audio output and mixer devices for this to work.