Projectwork Mobile Services

Transcription

1 Projectwork Mobile Services HMCS House Mobile Control System Valentin Ioan Tincas Jürgen Innerkofler 2007/2008

2 Project description:... 3 Used hardware components:... 3 Software implementation... 4 Communication protocol and technique... 4 Example:... 4 Mobile phone J2Me application... 5 Description... 5 Installing the java application... 8 Control unit CoDeSys application... 9 Description... 9 Implementation... 9 Problems and solution List of literature Used programs

3 Project description: The aim of the project is to create an application for a mobile phone using J2ME. This application provides a GUI to control the state your home (lights and heater). Also the application will be able to receive an alarm from the system located in the house (window and door event). Image 1: basic system scheme shows the demonstration set up with its components The home system is composed by the TTControl ECU (electrical control unit) a Siemens GSM module. States of heaters and lights are represented by some LEDs(Light emitting diods). Home switches to turn on the lights are simulated by buttons. In addition two buttons will simulate security sensors which monitor door or window events Used hardware components: Component Purpose Quantity Provided from Mobile phone run the control application 1 personal Control unit TTC-Vision implements home control system 1 TTControl Srl. GSM Module Siemens MC35i GSM connection from TTC-Vision 1 TTControl Srl. Wind SIM card needed for GSM module 1 personal Battery Packs LiPo 3s VSS DC Supply control unit 2 personal LED 12V simulate physical lights and heater 8 personal Electric button light switch 6 personal Electric button simulate alarm events (door, window) 2 personal Circuit board mount the electrical components 1 personal Table 1: Hardware component list 3

4 Software implementation Communication protocol and technique The information transfer is implemented using SMS (short message service) in text mode. The first five characters of the message form the code word -HMCS* and inform the applications that the message belongs to the Mobile House Control System. In this case further evaluations of the message content are processed and proper actions performed. Incoming SMS include additional header information which is stored in the next 1-2 characters. -HMCS* = this message belongs to the HMCS application -HMCS*RS =request state -HMCS*A = allarm information states are stored in following characters -HMCS*R = answer caused by a request state sms states are stored in following characters The information of the light and heater states are stored in a very simple way. A majuscule letter signalises that the proper entity is ON and a minuscule letter signalises the OFF state. The letter L implies that the light is switched on. Example: The content of the following SMS is send to the home system: -HMCS*LllLhHHh After receiving and decoding the SMS, the system will set the signal LED s according to the evaluated string which follows HMCS*. The next picture will show the resulting LED states Image 2: Example LED visualization of the models interface Note: All SMS are sent on a specified port. This is needed to wake the application up if a alarm SMS is received at the cell phone. The related part of the mobile phone operating system is called push registry. 4

5 Mobile phone J2Me application Description While working for our application we faced the port communication problem as the GSM module sends a regular SMS without specifying the port which the message should be sent to. That s why we implemented two versions of our application. 1. HomeMobileControlSystemMC35i (j2me application to GSM Module Siemens MC35i communication) The application provides a GUI to set the values of lights heaters in an appealing way. Accessing the menu Options allows the user to perform the action Ask Status which means sending this kind of code to the module: -HMCS*RS. As a consequence the application sends a SMS with the code word -HMCS*R to the preset HouseSystem phone number. After some time the requested states are sent via SMS from the system according to the specified protocol. Another action that is possible to be performed from the application is Send SMS which sends to the MC35i module the user options about the lights and heaters states. The leds at the module side are set up according to such message received. All SMS sent between this versions of the application and the module are regular messages sent to phone number and no port specified. Also in this version of the j2me application the phone number which the message is to be sent to, is represented by a StringItem object so cannot be changed at user interface. As at the GSM module side are 8 leds we have 8 ChoiceGroup objects on the user interface. Image 3: J2ME MC35i application GUI Image 4: J2ME MC35i application menu options This version of the application was tested with NetBeans IDE 6.0.1, Wireless Toolkit via OTA, on Nokia 5300 and Motorola W510. Works from real phone device. No port implemented. 5

6 2. HomeMobileControlSystem (j2me application to j2me application communication) As a difference from the previous described version now the interface uses Gauge objects to represent heaters. Another thing which is different is that the user is able to send a door or window event. Also different is the Ask Status code word -HMCS*Q. Image 5: J2ME application GUI Image 6: J2ME application menu options For this version of application we chose port In general for communication the ports from to are available for sending and receiving SMS. Using this port we implemented static push registry (.jad file modification) behaviour of application. This results in the fact that each time an sms is sent from the application to some mobile terminal which also has the application installed, even if not running HomeMobileControlSystem wakes up and handles the messages arriving at port (Wireless Toolkit > Run via OTA) Image 7: The application Sends SMS Image 8: The receiver updates the UI 6

7 In this way the application interface is updated each time a message is received at port For instance if we choose Ask status from the menu the request is sent to the chosen mobile terminal which answers back with another sms which will update the interface of the application which asked the status. Image 9: Asks Status Image 10: automatically replyes Image 11: UI updated Image 12: sent the status Information or warning alerts are used for all sms whether sent or received. This version of the application was tested with NetBeans IDE 6.0.1, Wireless Toolkit via OTA, on Nokia 5300 and Motorola W510 and worked fine. 7

8 Implementation The midlet HMCSMIDlet creates UI, starts receiving thread and the sending sms thread. The Sender class is used for sending sms only. MID Profile interfaces and classes used in the project: javax.microedition.io.connection; javax.microedition.lcdui. CommandListener, Alert, ChoiceGroup, Display, Form, Gauge, Item, TextBox, TextField; javax.microedition.midlet.midlet; The Wireless Messaging API javax.wireless.messaging.message. Other: Java.lang.Runnable. Image 13: Implementation diagram Installing the java application On Wireless Toolkit Copy HomeMobileControlSystem folder to C:\Users\<USERNAME>\j2mewtk\2.5.2\apps. Start Wireless Toolkit > Project > Run via OTA > select Install Application in the emulator and follow all the steps until installation is complete. (This is recommended.) Start Wireless Toolkit > Project > Run (in this case the push registry feature cannot be observed). On a real device Copy the HomeMobileControlSystem/bin/HomeMobileControlSystem.jad and HomeMobileControlSystem/bin/HomeMobileControlSystem.jar files from computer in one folder to the mobile phone using an usb cable and perform a standard installation of a java application. This is similar to the installation done when running on Wireless Toolkit via OTA but can differ from one device to another. The HomeMobileControlSystemMC35i is the project version used from phone to MC35i GSM module and it doesn t work on emulator. 8

9 Control unit CoDeSys application Description The control unit is programmed using CoDeSys programming environment and the included structured text language. The main tasks are the handling of the input switches and output ports as well as reading the SMS slots of the GSM module. If a SMS has to be send a outgoing SMS event is scheduled and processed at the next call of the HandleSmsEvent function. The system is designed to simulate the behaviour of a house with lights, heaters and two alarm sensors as mentioned in the project description Implementation Since the main task of the Project is the J2ME development, we will just give the following basic information The control unit has a cycle time of 10ms. That means the program code is executed each cycle and in case that more then 10ms are needed to compute the program (serial communication) the next 10ms are assigned to the computation. Reading input switches and setting output switches is done each time the code is executed. Checking the SMS storage slot of the GSM module and decoding the content as well as sending SMS are handled at different time slices. The time slices duration is 200 ms and is needed to give the GSM module some computation time to process the requests. Image 14: basic flow diagram of the CoDeSys application on the TTCVision 9

10 Problems and solution The our implementation of the GSM modules functionality isnt able to specify a SMS port number. The push registry feature of phones which support J2ME applications can only intercept SMS messages on a specific port. As a consequence any SMS from the GSM module couldn t be captured. So the application cant recive and evaluate SMS messages from the house system. The solution of this problem could be the next investigation to improve the system. Using binary SMS message transfer might solve the problem. List of literature [1] Mobile Services Handouts, Lecturer: Francesco Ricci [2] Sing Li and Jonathan Knudsen, Beginning J2ME, (3rd Ed.) Apress, 2005 [3] MC35i_ATC_V01.03.pdf - AT-Commands for modems Used programs (1) NetBeans IDE (2) CoDeSys 3.0 [3S] (3) Wireless Toolkit