net.wimpi.modbus.io
Class ModbusRTUTransport

java.lang.Object
  net.wimpi.modbus.io.ModbusSerialTransport
      net.wimpi.modbus.io.ModbusRTUTransport

All Implemented Interfaces:

ModbusTransport

public class ModbusRTUTransport
extends ModbusSerialTransport

Class that implements the ModbusRTU transport flavor.

Version:

@version@ (@date@)

Author:

John Charlton, Dieter Wimberger

Field Summary

private byte[]	lastRequest
private BytesInputStream	m_ByteIn
private BytesOutputStream	m_ByteInOut
private BytesOutputStream	m_ByteOut
private byte[]	m_InBuffer
private InputStream	m_InputStream
private OutputStream	m_OutputStream

Fields inherited from class net.wimpi.modbus.io.ModbusSerialTransport

m_CommPort, m_Echo

Constructor Summary

ModbusRTUTransport()

Method Summary

void	clearInput() Clear the input if characters are found in the input stream.
void	close() The close method closes the serial input/output streams.
private void	getResponse(int fn, BytesOutputStream out)
void	prepareStreams(InputStream in, OutputStream out) Prepares the input and output streams of this ModbusRTUTransport instance.
ModbusRequest	readRequest() The readRequest method listens continuously on the serial input stream for master request messages and replies if the request slave ID matches its own set in ModbusCoupler.getUnitID().
ModbusResponse	readResponse() readResponse reads a response message from the slave responding to a master writeMessage request.
void	writeMessage(ModbusMessage msg) The writeMessage method writes a modbus serial message to its serial output stream to a specified slave unit ID.

Methods inherited from class net.wimpi.modbus.io.ModbusSerialTransport

isEcho, readEcho, setCommPort, setEcho, setReceiveThreshold, setReceiveTimeout

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

m_InputStream

private InputStream m_InputStream

m_OutputStream

private OutputStream m_OutputStream

m_InBuffer

private byte[] m_InBuffer

m_ByteIn

private BytesInputStream m_ByteIn

m_ByteInOut

private BytesOutputStream m_ByteInOut

m_ByteOut

private BytesOutputStream m_ByteOut

lastRequest

private byte[] lastRequest

Constructor Detail

ModbusRTUTransport

public ModbusRTUTransport()

Method Detail

writeMessage

public void writeMessage(ModbusMessage msg)
                  throws ModbusIOException

Description copied from class: ModbusSerialTransport

The writeMessage method writes a modbus serial message to its serial output stream to a specified slave unit ID.

Specified by:

writeMessage in interface ModbusTransport

Specified by:

writeMessage in class ModbusSerialTransport

Parameters:

msg - a ModbusMessage value

Throws:

ModbusIOException - if an error occurs

readRequest

public ModbusRequest readRequest()
                          throws ModbusIOException

Description copied from class: ModbusSerialTransport

The readRequest method listens continuously on the serial input stream for master request messages and replies if the request slave ID matches its own set in ModbusCoupler.getUnitID().

Specified by:

readRequest in interface ModbusTransport

Specified by:

readRequest in class ModbusSerialTransport

Returns:

a ModbusRequest value

Throws:

ModbusIOException - if an error occurs

clearInput

public void clearInput()
                throws IOException

Clear the input if characters are found in the input stream.

Throws:

IOException

readResponse

public ModbusResponse readResponse()
                            throws ModbusIOException

Description copied from class: ModbusSerialTransport

readResponse reads a response message from the slave responding to a master writeMessage request.

Specified by:

readResponse in interface ModbusTransport

Specified by:

readResponse in class ModbusSerialTransport

Returns:

a ModbusResponse value

Throws:

ModbusIOException - if an error occurs

prepareStreams

public void prepareStreams(InputStream in,
                           OutputStream out)
                    throws IOException

Prepares the input and output streams of this ModbusRTUTransport instance.

Specified by:

prepareStreams in class ModbusSerialTransport

Parameters:

in - the input stream to be read from.

out - the output stream to write to.

Throws:

IOException - if an I\O error occurs.

close

public void close()
           throws IOException

Description copied from class: ModbusSerialTransport

The close method closes the serial input/output streams.

Specified by:

close in interface ModbusTransport

Specified by:

close in class ModbusSerialTransport

Throws:

IOException - if an error occurs

getResponse

private void getResponse(int fn,
                         BytesOutputStream out)
                  throws IOException

Throws:

IOException