QModbusTcpServer Class
The QModbusTcpServer class represents a Modbus server that uses a TCP server for its communication with the Modbus client. More...
| Header: | #include <QModbusTcpServer> |
| qmake: | QT += serialbus |
| Since: | Qt 5.8 |
| Inherits: | QModbusServer |
Public Functions
| QModbusTcpServer(QObject *parent = nullptr) | |
| virtual | ~QModbusTcpServer() |
- 10 public functions inherited from QModbusServer
- 7 public functions inherited from QModbusDevice
- 34 public functions inherited from QObject
Reimplemented Protected Functions
| virtual void | close() override |
| virtual bool | open() override |
| virtual QModbusResponse | processRequest(const QModbusPdu &request) override |
- 4 protected functions inherited from QModbusServer
- 4 protected functions inherited from QModbusDevice
- 9 protected functions inherited from QObject
Additional Inherited Members
- 1 property inherited from QObject
- 1 public slot inherited from QObject
- 1 signal inherited from QModbusServer
- 2 signals inherited from QModbusDevice
- 2 signals inherited from QObject
- 1 public variable inherited from QObject
- 10 static public members inherited from QObject
- 4 protected functions inherited from QModbusServer
- 4 protected functions inherited from QModbusDevice
- 9 protected functions inherited from QObject
- 2 protected variables inherited from QObject
Detailed Description
The QModbusTcpServer class represents a Modbus server that uses a TCP server for its communication with the Modbus client.
Communication via Modbus requires the interaction between a single Modbus client instance and single Modbus server. This class provides the Modbus server implementation via a TCP server.
Modbus TCP networks can have multiple servers. Servers are read/written by a client device represented by QModbusTcpClient.
Member Function Documentation
QModbusTcpServer::QModbusTcpServer(QObject *parent = nullptr)
Constructs a QModbusTcpServer with the specified parent. The serverAddress preset is 255.
[virtual] QModbusTcpServer::~QModbusTcpServer()
Destroys the QModbusTcpServer instance.
[override virtual protected] void QModbusTcpServer::close()
Reimplemented from QModbusDevice::close().
[override virtual protected] bool QModbusTcpServer::open()
Reimplemented from QModbusDevice::open().
[override virtual protected] QModbusResponse QModbusTcpServer::processRequest(const QModbusPdu &request)
Reimplemented from QModbusServer::processRequest().
Processes the Modbus client request specified by request and returns a Modbus response.
The following Modbus function codes are filtered out as they are serial line only according to the Modbus Application Protocol Specification 1.1b:
- QModbusRequest::ReadExceptionStatus
- QModbusRequest::Diagnostics
- QModbusRequest::GetCommEventCounter
- QModbusRequest::GetCommEventLog
- QModbusRequest::ReportServerId
A request to the TCP server will be answered with a Modbus exception response with the exception code QModbusExceptionResponse::IllegalFunction.