问J2mod从保持寄存器读取不同的值

EN

 ModbusSerialTransaction trans = null;
       ReadMultipleRegistersRequest req = null;
       ReadMultipleRegistersResponse res = null;

       int unitid = 1; //the unit identifier we will be talking to
       int ref = 40050; //the reference, where to start reading from
       int count = 5; //the count of IR's to read
       int repeat = 1; //a loop for repeating the transaction

       //4. Open the connection
       try {

           //5. Prepare a request
           req = new ReadMultipleRegistersRequest(ref, count);
           req.setUnitID(unitid);
           req.setHeadless();

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

           int k = 0;
           do {
               trans.setTransDelayMS(50);
               trans.execute();
               res = (ReadMultipleRegistersResponse) trans.getResponse();
               for (int n = 0; n < res.getWordCount(); n++) {
                   System.out.println("Word " + n + "=" + res.getRegisterValue(n));
               }
               k++;
           } while (k < repeat);
           con.close();
           //8. Close the connection
       } catch (ModbusException ex) {
          System.out.print(ex);
       }

please check this code.