JAMOD FC01 "Read Coils" with MODBUS ASCII protocol

SerialAscCoilsTest.java

/**
 * Copyright 2002-2010 jamod development team
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ***/

package net.wimpi.modbus.cmd;

import net.wimpi.modbus.Modbus;
import net.wimpi.modbus.ModbusCoupler;
import net.wimpi.modbus.io.ModbusSerialTransaction;
import net.wimpi.modbus.msg.ReadCoilsRequest;
import net.wimpi.modbus.msg.ReadCoilsResponse;
import net.wimpi.modbus.net.SerialConnection;
import net.wimpi.modbus.util.BitVector;
import net.wimpi.modbus.util.SerialParameters;

/**
 * Class that implements a simple commandline
 * tool for reading an analog input.
 *
 * @author Dieter Wimberger
 * @version @version@ (@date@)
 */
public class SerialAscCoilsTest {

    public static void main(String[] args) {

        SerialConnection con = null;
        ModbusSerialTransaction trans = null;
        ReadCoilsRequest req = null;
        ReadCoilsResponse res = null;

        String portname = null;
        int unitid = 0;
        int ref = 0;
        int count = 0;
        int repeat = 1;

        try {

            // 1. Setup the parameters
            if (args.length < 4) {
                printUsage();
                System.exit(1);
            } else {
                try {
                    portname = args[0];
                    unitid = Integer.parseInt(args[1]);
                    ref = Integer.parseInt(args[2]);
                    count = Integer.parseInt(args[3]);
                    if (args.length == 5) {
                        repeat = Integer.parseInt(args[4]);
                    }
                } catch (Exception ex) {
                    ex.printStackTrace();
                    printUsage();
                    System.exit(1);
                }
            }

            // 2. Set slave identifier for master response parsing
            ModbusCoupler.getReference().setUnitID(unitid);

            System.out.println("net.wimpi.modbus.debug set to: " + System.getProperty("net.wimpi.modbus.debug"));

            // 3. Setup serial parameters
            SerialParameters params = new SerialParameters();
            params.setPortName(portname);
            params.setBaudRate(9600);
            params.setDatabits(8);
            params.setParity("None");
            params.setStopbits(1);
            params.setEncoding("ascii");
            // params.setEcho(false);
            if (Modbus.debug) {
                System.out.println("Encoding [" + params.getEncoding() + "]");
            }

            // 4. Open the connection
            con = new SerialConnection(params);
            con.open();

            // 5. Prepare a request
            req = new ReadCoilsRequest(ref, count);
            req.setUnitID(unitid);
            req.setHeadless();
            if (Modbus.debug) {
                System.out.println("Request: " + req.getHexMessage());
            }

            // 6. Prepare the transaction
            trans = new ModbusSerialTransaction(con);
            trans.setRequest(req);

            // 7. Execute the transaction repeat times
            int k = 0;
            do {
                trans.execute();

                res = (ReadCoilsResponse) trans.getResponse();
                // if (Modbus.debug) {
                    System.out.println("Response: " + res.getHexMessage());
                // }
                BitVector inputs = res.getCoils();
                byte ret[] = new byte[inputs.size()];
                for (int i = 0; i < count; i++) {
                    System.out.println("Bit " + i + " = " + inputs.getBit(i));
                }

                k++;
            } while (k < repeat);

            // 8. Close the connection
            con.close();

        } catch (Exception ex) {
            ex.printStackTrace();
            // Close the connection
            con.close();
        }
    }// main

    private static void printUsage() {
        System.out.println(
                "java net.wimpi.modbus.cmd.SerialAscCoilsTest <portname [String]>  <Unit Address [int8]> <register [int16]> <wordcount [int16]> {<repeat [int]>}");
    }// printUsage

}// class SerialAscCoilsTest

• save as src/main/java/net/wimpi/modbus/cmd/SerialAscCoilsTest.java
• compile with mvn package
• run with e.g. ava -cp "target/jamod-1.2.3.OH-SNAPSHOT.jar:target/dependency/*" net.wimpi.modbus.cmd.SerialAscCoilsTest /dev/ttyUSB1 1 2 16