add Modbus part

link with DataPoints will be made in Field part

src/main/java/ch/hevs/isi/field/ModbusAccessor.java

@@ -0,0 +1,159 @@
+package ch.hevs.isi.field;
+
+import com.serotonin.modbus4j.ModbusFactory;
+import com.serotonin.modbus4j.ModbusMaster;
+import com.serotonin.modbus4j.code.DataType;
+import com.serotonin.modbus4j.exception.ErrorResponseException;
+import com.serotonin.modbus4j.exception.ModbusInitException;
+import com.serotonin.modbus4j.exception.ModbusTransportException;
+import com.serotonin.modbus4j.ip.IpParameters;
+import com.serotonin.modbus4j.ip.tcp.TcpMaster;
+import com.serotonin.modbus4j.locator.BaseLocator;
+
+public class ModbusAccessor {
+
+    private static ModbusAccessor mySelf = null;        //instance of the class
+    private ModbusMaster master = null;                 //instance of the modbus master
+
+    /**
+     * private constructor
+     * */
+    private ModbusAccessor(){
+
+    }
+
+    /**
+     * static method to create a singleton pattern of the class
+     * checks if an instance of the class is already made
+     * if not, it creates an instance of the class ModbusAccessor
+     * @return instance of ModbusAccessor
+     */
+    public static ModbusAccessor getMySelf(){
+        if (mySelf == null){                    //if no instance is created
+            mySelf = new ModbusAccessor();      //create a new instance of the class
+        }
+        return mySelf;                          //if there is already an instance, return the existing instance
+    }
+
+    /**
+     *  this method creates a ModbusFactory and a TCPMaster
+     *  it also initialize the Master
+     * @param ipAddress IP-address of the server
+     * @param port port of the server
+     */
+    public void connect(String ipAddress, int port){
+        ModbusFactory MF = new ModbusFactory();         //create a modbus factory
+        IpParameters IpParams = new IpParameters();     //create the ip parameters
+
+        IpParams.setHost(ipAddress);        //set the server ip-address
+        IpParams.setPort(port);             //set the server port
+
+        //create the TCPMaster with the correct IP parameters and keep it alive
+        this.master = MF.createTcpMaster(IpParams, true);
+        try {
+            this.master.init();         //initialize the master
+        }
+        catch(ModbusInitException e)
+        {
+            e.printStackTrace();
+        }
+    }
+    //methods to write
+    /**
+     * method to write a boolean value in the correct modbus register
+     * @param register address of the register
+     * @param value the desired boolean value
+     * @throws ModbusTransportException
+     * @throws ErrorResponseException
+     */
+    public void writeBoolean (int register, boolean value) throws ModbusTransportException, ErrorResponseException{
+        //first parameter = slaveID = always 1 because we only have one
+        //second parameter = register address ==> it is named offset because it starts with 0 and goes to the desired address
+        this.master.setValue(BaseLocator.coilStatus(1,register), value); //set the desired value in the correct register
+    }
+
+    /**
+     * method to write a float value in the correct modbus register
+     * @param register address of the register
+     * @param value the desired float value
+     * @throws ModbusTransportException
+     * @throws ErrorResponseException
+     */
+    public void writeFloat (int register, float value) throws ModbusTransportException, ErrorResponseException{
+        //first parameter = slaveID = always 1 because we only have one
+        //second parameter = register address ==> it is named offset because it starts with 0 and goes to the desired address
+        //third parameter = DataType of the value. The max value is 3 Byte Float, but the class DataType has only 2 or 4 byte
+        this.master.setValue(BaseLocator.holdingRegister(1,register,DataType.FOUR_BYTE_FLOAT), value);
+    }
+    //methods to read
+    /**
+     * method to read a boolean value in the correct modbus register
+     * get the coil status of the register.
+     * @param register address of register
+     * @return boolean value of the desired register
+     * @throws ModbusTransportException
+     * @throws ErrorResponseException
+     */
+    public boolean readBoolean(int register) throws ModbusTransportException, ErrorResponseException {
+        //first parameter = slaveID = always 1 because we only have one
+        //second parameter = register address ==> it is named offset because it starts with 0 and goes to the desired address
+        boolean booleanValue = this.master.getValue(BaseLocator.coilStatus(1,register));
+        return booleanValue;
+    }
+    /**
+     * method to read a boolean value in the correct modbus register
+     * get the value from the holding register
+     * @param register address of the register
+     * @return float value of the desired register
+     * @throws ModbusTransportException
+     * @throws ErrorResponseException
+     */
+    public float readFloat(int register)throws ModbusTransportException, ErrorResponseException{
+        //first parameter = slaveID = always 1 because we only have one
+        //second parameter = register address ==> it is named offset because it starts with 0 and goes to the desired address
+        //third parameter = DataType of the value. The max value is 3 Byte Float, but the class DataType has only 2 or 4 byte
+        float floatValue = (float) this.master.getValue(BaseLocator.holdingRegister(1,register, DataType.FOUR_BYTE_FLOAT));
+        return floatValue;
+    }
+    /**
+     * this main method is only for testing the ModbusAccessor class
+     * @param args
+     */
+    public static void main(String[] args) {
+        //create an instance of ModbusAccessor and connect it with the server
+        ModbusAccessor test = ModbusAccessor.getMySelf();
+        test.connect("LocalHost", 1502);
+        //do this all the time
+        while(true){
+            try{
+                //get a boolean value => solar SetPoint
+                boolean solar_connect_st = test.readBoolean(609);           //SOLAR_CONNECT_ST
+                //get a float value => factory SetPoint
+                float factory_st = test.readFloat(605);                     //FACTORY_ST
+
+                //write a float value to the Remote_Factory_SP
+                test.writeFloat(205,0.56F);                         //REMOTE_FACTORY_SP
+                //write a boolean value to the Remote_Solar_SW
+                test.writeBoolean(401,false);                       //REMOTE_SOLAR_SW
+
+                //check the factory SetPoint
+                System.out.println("Factory Setpoint is: " + factory_st);
+
+                //check the solar SetPoint
+                if(solar_connect_st){
+                    System.out.println("Solar is connected");
+                }else{
+                    System.out.println("Solar is disconnected");
+                }
+            }catch (ModbusTransportException e){
+
+            }catch (ErrorResponseException e){
+
+            }
+        }
+    }
+}
+
+
+
+