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36
37#include "qmodbusrtuserialslave.h"
38#include "qmodbusrtuserialslave_p.h"
39
40#include <QtCore/qloggingcategory.h>
41
42QT_BEGIN_NAMESPACE
43
44/*!
45 \class QModbusRtuSerialSlave
46 \inmodule QtSerialBus
47 \since 5.8
48
49 \brief The QModbusRtuSerialSlave class represents a Modbus server
50 that uses a serial port for its communication with the Modbus client.
51
52 Communication via Modbus requires the interaction between a single Modbus
53 client instance and multiple Modbus server. This class provides the Modbus
54 server implementation via a serial port.
55
56 Since multiple Modbus server instances can interact with a Modbus client
57 at the same time (using a serial bus), servers are identified by their
58 \l serverAddress().
59*/
60
61/*!
62 Constructs a QModbusRtuSerialSlave with the specified \a parent. The
63 \l serverAddress preset is \c 1.
64*/
65QModbusRtuSerialSlave::QModbusRtuSerialSlave(QObject *parent)
66 : QModbusServer(*new QModbusRtuSerialSlavePrivate, parent)
67{
68 Q_D(QModbusRtuSerialSlave);
69 d->setupSerialPort();
70}
71
72/*!
73 Destroys the QModbusRtuSerialSlave instance.
74*/
75QModbusRtuSerialSlave::~QModbusRtuSerialSlave()
76{
77 close();
78}
79
80/*!
81 \internal
82*/
83QModbusRtuSerialSlave::QModbusRtuSerialSlave(QModbusRtuSerialSlavePrivate &dd, QObject *parent)
84 : QModbusServer(dd, parent)
85{
86 Q_D(QModbusRtuSerialSlave);
87 d->setupSerialPort();
88}
89
90/*!
91 \reimp
92*/
93bool QModbusRtuSerialSlave::processesBroadcast() const
94{
95 return d_func()->m_processesBroadcast;
96}
97
98/*!
99 \reimp
100
101 \note When calling this function, existing buffered data is removed from
102 the serial port.
103*/
104bool QModbusRtuSerialSlave::open()
105{
106 if (state() == QModbusDevice::ConnectedState)
107 return true;
108
109 Q_D(QModbusRtuSerialSlave);
110 d->setupEnvironment(); // to be done before open
111 if (d->m_serialPort->open(mode: QIODevice::ReadWrite)) {
112 setState(QModbusDevice::ConnectedState);
113 d->m_serialPort->clear(); // only possible after open
114 } else {
115 setError(errorText: d->m_serialPort->errorString(), error: QModbusDevice::ConnectionError);
116 }
117 return (state() == QModbusDevice::ConnectedState);
118}
119
120/*!
121 \reimp
122*/
123void QModbusRtuSerialSlave::close()
124{
125 if (state() == QModbusDevice::UnconnectedState)
126 return;
127
128 Q_D(QModbusRtuSerialSlave);
129 if (d->m_serialPort->isOpen())
130 d->m_serialPort->close();
131
132 setState(QModbusDevice::UnconnectedState);
133}
134
135/*!
136 \reimp
137
138 Processes the Modbus client request specified by \a request and returns a
139 Modbus response.
140
141 The Modbus function \l QModbusRequest::EncapsulatedInterfaceTransport with
142 MEI Type 13 (0x0D) CANopen General Reference is filtered out because it is
143 usually Modbus TCP or Modbus serial ASCII only.
144
145 A request to the RTU serial slave will be answered with a Modbus exception
146 response with the exception code QModbusExceptionResponse::IllegalFunction.
147*/
148QModbusResponse QModbusRtuSerialSlave::processRequest(const QModbusPdu &request)
149{
150 if (request.functionCode() == QModbusRequest::EncapsulatedInterfaceTransport) {
151 quint8 meiType;
152 request.decodeData(newData: &meiType);
153 if (meiType == EncapsulatedInterfaceTransport::CanOpenGeneralReference) {
154 return QModbusExceptionResponse(request.functionCode(),
155 QModbusExceptionResponse::IllegalFunction);
156 }
157 }
158 return QModbusServer::processRequest(request);
159}
160
161QT_END_NAMESPACE
162
163#include "moc_qmodbusrtuserialslave.cpp"
164

source code of qtserialbus/src/serialbus/qmodbusrtuserialslave.cpp