This LCARS home automation from YouTube user boltszmann138 a trekkies dream come true!
…I came to the conclusion that QT works fine for me. There are two programms running:
First, there is “ha_interface” on the raspberry which on the one hand connects to the arduino via usb and provides a tcp server for clients on the other hand. Clients can request sensor values by sending “request:sensortype:sensorid” over a simple QTcpSocket. If the arduino sends an interrupt (for example: reed contact 1 is now open), ha_interface sends a broadcast message like “broadcast:reed1:opened” to all connected clients. Parsing of these commands can easily be done via the QString::split(“:”) function. The biggest problem was: I dont want the clients to poll for the reed contact state, since they change very seldom. On the other hand, I didnt want to miss that event. So I had to find a way how recognize an interrupt (by emitting a signal) in the serial usb connection. This gave me the answer: http://www.webalice.it/fede.tft/seria… (part 5) and http://fedetft.wordpress.com/2010/04/… . Several connected clients can talk to each other via the interface and share for example their local “red alert on” or “system locked” bool variables.
The second program, “ha_gui” is the LCARS design you can see in the video (the final version will get a dedicated 24″ touch screen :-D). This program connects to the ha_interface programm via QTcpSocket. When switching an outlet, it sends “switchOutlet:syscode:groupcode:mode” to the interface, when requesting the temperature sensors, it sends “request:temperature:1″ or something like that to the interface. If the main door is openend, the arduino will recognize that and send a message to the interface which then broadcasts that information to all connected clients. This LCARS client will play the “red alert” sound from Star Trek Voyager if that happens. Playing sounds is done via “QProcess::startDetached(“aplay PATH_TO_FILE”). The “analysis of sensor data” at the top is realized via 7 QLineEdits. There is a QTimer which is called periodically, it generates random numbers and sometimes highlights a row. The LCARS design was created in QT Designer. There are stylesheet options for rounded corners and you can find official LCARS colors via google. The different views are realized by a QStackedWidget.
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