QT官方modbus_slave例子嵌入到界面

1.打开QT官方modbus_slave的例子

根据提示略微配置一下编译选项，就可以正常运行。

2.新将一个项目包含这个例子

这个例子非常简单，就是在默认的mainwindow上给个按钮，点击按钮调用这个例子的界面。 

 

3.修改*.pro文件

serialport serialbus 增加这两个库，如下图划线处。

 4.复制源文件并修改名字

将例子中的mainwindow.h修改成modbus.h，文件里面对应的名字也进行修改。

为了直接可以用，此处粘贴源码如下：

/****************************************************************************
**
** Copyright (C) 2017 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the examples of the QtSerialBus module.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, you may use this file under the terms of the BSD license
** as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**   * Redistributions of source code must retain the above copyright
**     notice, this list of conditions and the following disclaimer.
**   * Redistributions in binary form must reproduce the above copyright
**     notice, this list of conditions and the following disclaimer in
**     the documentation and/or other materials provided with the
**     distribution.
**   * Neither the name of The Qt Company Ltd nor the names of its
**     contributors may be used to endorse or promote products derived
**     from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef MODBUS_H
#define MODBUS_H

#include <QButtonGroup>
#include <QMainWindow>
#include <QModbusServer>

QT_BEGIN_NAMESPACE

class QLineEdit;

namespace Ui {
class modbus;
class SettingsDialog;
}

QT_END_NAMESPACE

class SettingsDialog;

class modbus : public QMainWindow
{
    Q_OBJECT

public:
    explicit modbus(QWidget *parent = nullptr);
    ~modbus();

private Q_SLOTS:
    void onConnectButtonClicked();
    void onStateChanged(int state);

    void coilChanged(int id);
    void discreteInputChanged(int id);
    void bitChanged(int id, QModbusDataUnit::RegisterType table, bool value);

    void setRegister(const QString &value);
    void updateWidgets(QModbusDataUnit::RegisterType table, int address, int size);

    void onCurrentConnectTypeChanged(int);

    void handleDeviceError(QModbusDevice::Error newError);

private:
    void initActions();
    void setupDeviceData();
    void setupWidgetContainers();

    Ui::modbus *ui = nullptr;
    QModbusServer *modbusDevice = nullptr;

    QButtonGroup coilButtons;
    QButtonGroup discreteButtons;
    QHash<QString, QLineEdit *> registers;
    SettingsDialog *m_settingsDialog = nullptr;
};

#endif // MODBUS_H

 

 将例子中的mainwindow.cpp修改成modbus.cpp，里面对应的可以查找替换，这个里面的比较多。

 

/****************************************************************************
**
** Copyright (C) 2017 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the examples of the QtSerialBus module.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, you may use this file under the terms of the BSD license
** as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**   * Redistributions of source code must retain the above copyright
**     notice, this list of conditions and the following disclaimer.
**   * Redistributions in binary form must reproduce the above copyright
**     notice, this list of conditions and the following disclaimer in
**     the documentation and/or other materials provided with the
**     distribution.
**   * Neither the name of The Qt Company Ltd nor the names of its
**     contributors may be used to endorse or promote products derived
**     from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "modbus.h"
#include "settingsdialog.h"
#include "ui_modbus.h"

#include <QModbusRtuSerialSlave>
#include <QModbusTcpServer>
#include <QRegularExpression>
#include <QRegularExpressionValidator>
#include <QStatusBar>
#include <QUrl>

enum ModbusConnection {
   Tcp,
   Serial

};

modbus::modbus(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::modbus)
{
    ui->setupUi(this);
    setupWidgetContainers();

#if QT_CONFIG(modbus_serialport)
    ui->connectType->setCurrentIndex(0);
    onCurrentConnectTypeChanged(0);
#else
    // lock out the serial port option
    ui->connectType->setCurrentIndex(1);
    onCurrentConnectTypeChanged(1);
    ui->connectType->setEnabled(false);
#endif

    m_settingsDialog = new SettingsDialog(this);
    initActions();
}

modbus::~modbus()
{
    if (modbusDevice)
        modbusDevice->disconnectDevice();
    delete modbusDevice;

    delete ui;
}

void modbus::initActions()
{
    ui->actionConnect->setEnabled(true);
    ui->actionDisconnect->setEnabled(false);
    ui->actionExit->setEnabled(true);
    ui->actionOptions->setEnabled(true);

    connect(ui->connectButton, &QPushButton::clicked,
            this, &modbus::onConnectButtonClicked);
    connect(ui->actionConnect, &QAction::triggered,
            this, &modbus::onConnectButtonClicked);
    connect(ui->actionDisconnect, &QAction::triggered,
            this, &modbus::onConnectButtonClicked);
    connect(ui->connectType, QOverload<int>::of(&QComboBox::currentIndexChanged),
            this, &modbus::onCurrentConnectTypeChanged);

    connect(ui->actionExit, &QAction::triggered, this, &QMainWindow::close);
    connect(ui->actionOptions, &QAction::triggered, m_settingsDialog, &QDialog::show);
}

void modbus::onCurrentConnectTypeChanged(int index)
{
    if (modbusDevice) {
        modbusDevice->disconnect();
        delete modbusDevice;
        modbusDevice = nullptr;
    }

    auto type = static_cast<ModbusConnection>(index);
    if (type == Serial) {
#if QT_CONFIG(modbus_serialport)
        modbusDevice = new QModbusRtuSerialSlave(this);
#endif
    } else if (type == Tcp) {
        modbusDevice = new QModbusTcpServer(this);
        if (ui->portEdit->text().isEmpty())
            ui->portEdit->setText(QLatin1String("127.0.0.1:502"));
    }
    ui->listenOnlyBox->setEnabled(type == Serial);

    if (!modbusDevice) {
        ui->connectButton->setDisabled(true);
        if (type == Serial)
            statusBar()->showMessage(tr("Could not create Modbus slave."), 5000);
        else
            statusBar()->showMessage(tr("Could not create Modbus server."), 5000);
    } else {
        QModbusDataUnitMap reg;
        reg.insert(QModbusDataUnit::Coils, { QModbusDataUnit::Coils, 0, 10 });
        reg.insert(QModbusDataUnit::DiscreteInputs, { QModbusDataUnit::DiscreteInputs, 0, 10 });
        reg.insert(QModbusDataUnit::InputRegisters, { QModbusDataUnit::InputRegisters, 0, 10 });
        reg.insert(QModbusDataUnit::HoldingRegisters, { QModbusDataUnit::HoldingRegisters, 0, 10 });

        modbusDevice->setMap(reg);

        connect(modbusDevice, &QModbusServer::dataWritten,
                this, &modbus::updateWidgets);
        connect(modbusDevice, &QModbusServer::stateChanged,
                this, &modbus::onStateChanged);
        connect(modbusDevice, &QModbusServer::errorOccurred,
                this, &modbus::handleDeviceError);

        connect(ui->listenOnlyBox, &QCheckBox::toggled, this, [this](bool toggled) {
            if (modbusDevice)
                modbusDevice->setValue(QModbusServer::ListenOnlyMode, toggled);
        });
        emit ui->listenOnlyBox->toggled(ui->listenOnlyBox->isChecked());
        connect(ui->setBusyBox, &QCheckBox::toggled, this, [this](bool toggled) {
            if (modbusDevice)
                modbusDevice->setValue(QModbusServer::DeviceBusy, toggled ? 0xffff : 0x0000);
        });
        emit ui->setBusyBox->toggled(ui->setBusyBox->isChecked());

        setupDeviceData();
    }
}

void modbus::handleDeviceError(QModbusDevice::Error newError)
{
    if (newError == QModbusDevice::NoError || !modbusDevice)
        return;

    statusBar()->showMessage(modbusDevice->errorString(), 5000);
}

void modbus::onConnectButtonClicked()
{
    bool intendToConnect = (modbusDevice->state() == QModbusDevice::UnconnectedState);

    statusBar()->clearMessage();

    if (intendToConnect) {
        if (static_cast<ModbusConnection>(ui->connectType->currentIndex()) == Serial) {
            modbusDevice->setConnectionParameter(QModbusDevice::SerialPortNameParameter,
                ui->portEdit->text());
#if QT_CONFIG(modbus_serialport)
            modbusDevice->setConnectionParameter(QModbusDevice::SerialParityParameter,
                m_settingsDialog->settings().parity);
            modbusDevice->setConnectionParameter(QModbusDevice::SerialBaudRateParameter,
                m_settingsDialog->settings().baud);
            modbusDevice->setConnectionParameter(QModbusDevice::SerialDataBitsParameter,
                m_settingsDialog->settings().dataBits);
            modbusDevice->setConnectionParameter(QModbusDevice::SerialStopBitsParameter,
                m_settingsDialog->settings().stopBits);
#endif
        } else {
            const QUrl url = QUrl::fromUserInput(ui->portEdit->text());
            modbusDevice->setConnectionParameter(QModbusDevice::NetworkPortParameter, url.port());
            modbusDevice->setConnectionParameter(QModbusDevice::NetworkAddressParameter, url.host());
        }
        modbusDevice->setServerAddress(ui->serverEdit->text().toInt());
        if (!modbusDevice->connectDevice()) {
            statusBar()->showMessage(tr("Connect failed: ") + modbusDevice->errorString(), 5000);
        } else {
            ui->actionConnect->setEnabled(false);
            ui->actionDisconnect->setEnabled(true);
        }
    } else {
        modbusDevice->disconnectDevice();
        ui->actionConnect->setEnabled(true);
        ui->actionDisconnect->setEnabled(false);
    }
}

void modbus::onStateChanged(int state)
{
    bool connected = (state != QModbusDevice::UnconnectedState);
    ui->actionConnect->setEnabled(!connected);
    ui->actionDisconnect->setEnabled(connected);

    if (state == QModbusDevice::UnconnectedState)
        ui->connectButton->setText(tr("Connect"));
    else if (state == QModbusDevice::ConnectedState)
        ui->connectButton->setText(tr("Disconnect"));
}

void modbus::coilChanged(int id)
{
    QAbstractButton *button = coilButtons.button(id);
    bitChanged(id, QModbusDataUnit::Coils, button->isChecked());
}

void modbus::discreteInputChanged(int id)
{
    QAbstractButton *button = discreteButtons.button(id);
    bitChanged(id, QModbusDataUnit::DiscreteInputs, button->isChecked());
}

void modbus::bitChanged(int id, QModbusDataUnit::RegisterType table, bool value)
{
    if (!modbusDevice)
        return;

    if (!modbusDevice->setData(table, quint16(id), value))
        statusBar()->showMessage(tr("Could not set data: ") + modbusDevice->errorString(), 5000);
}

void modbus::setRegister(const QString &value)
{
    if (!modbusDevice)
        return;

    const QString objectName = QObject::sender()->objectName();
    if (registers.contains(objectName)) {
        bool ok = true;
        const quint16 id = quint16(QObject::sender()->property("ID").toUInt());
        if (objectName.startsWith(QStringLiteral("inReg")))
            ok = modbusDevice->setData(QModbusDataUnit::InputRegisters, id, value.toUShort(&ok, 16));
        else if (objectName.startsWith(QStringLiteral("holdReg")))
            ok = modbusDevice->setData(QModbusDataUnit::HoldingRegisters, id, value.toUShort(&ok, 16));

        if (!ok)
            statusBar()->showMessage(tr("Could not set register: ") + modbusDevice->errorString(),
                                     5000);
    }
}

void modbus::updateWidgets(QModbusDataUnit::RegisterType table, int address, int size)
{
    for (int i = 0; i < size; ++i) {
        quint16 value;
        QString text;
        switch (table) {
        case QModbusDataUnit::Coils:
            modbusDevice->data(QModbusDataUnit::Coils, quint16(address + i), &value);
            coilButtons.button(address + i)->setChecked(value);
            break;
        case QModbusDataUnit::HoldingRegisters:
            modbusDevice->data(QModbusDataUnit::HoldingRegisters, quint16(address + i), &value);
            registers.value(QStringLiteral("holdReg_%1").arg(address + i))->setText(text
                .setNum(value, 16));
            break;
        default:
            break;
        }
    }
}

// -- private

void modbus::setupDeviceData()
{
    if (!modbusDevice)
        return;

    for (quint16 i = 0; i < coilButtons.buttons().count(); ++i)
        modbusDevice->setData(QModbusDataUnit::Coils, i, coilButtons.button(i)->isChecked());

    for (quint16 i = 0; i < discreteButtons.buttons().count(); ++i) {
        modbusDevice->setData(QModbusDataUnit::DiscreteInputs, i,
            discreteButtons.button(i)->isChecked());
    }

    bool ok;
    for (QLineEdit *widget : qAsConst(registers)) {
        if (widget->objectName().startsWith(QStringLiteral("inReg"))) {
            modbusDevice->setData(QModbusDataUnit::InputRegisters, quint16(widget->property("ID").toUInt()),
                widget->text().toUShort(&ok, 16));
        } else if (widget->objectName().startsWith(QStringLiteral("holdReg"))) {
            modbusDevice->setData(QModbusDataUnit::HoldingRegisters, quint16(widget->property("ID").toUInt()),
                widget->text().toUShort(&ok, 16));
        }
    }
}

void modbus::setupWidgetContainers()
{
    coilButtons.setExclusive(false);
    discreteButtons.setExclusive(false);

    QRegularExpression regexp(QStringLiteral("coils_(?<ID>\\d+)"));
    const QList<QCheckBox *> coils = findChildren<QCheckBox *>(regexp);
    for (QCheckBox *cbx : coils)
        coilButtons.addButton(cbx, regexp.match(cbx->objectName()).captured("ID").toInt());
    connect(&coilButtons, SIGNAL(buttonClicked(int)), this, SLOT(coilChanged(int)));

    regexp.setPattern(QStringLiteral("disc_(?<ID>\\d+)"));
    const QList<QCheckBox *> discs = findChildren<QCheckBox *>(regexp);
    for (QCheckBox *cbx : discs)
        discreteButtons.addButton(cbx, regexp.match(cbx->objectName()).captured("ID").toInt());
    connect(&discreteButtons, SIGNAL(buttonClicked(int)), this, SLOT(discreteInputChanged(int)));

    regexp.setPattern(QLatin1String("(in|hold)Reg_(?<ID>\\d+)"));
    const QList<QLineEdit *> qle = findChildren<QLineEdit *>(regexp);
    for (QLineEdit *lineEdit : qle) {
        registers.insert(lineEdit->objectName(), lineEdit);
        lineEdit->setProperty("ID", regexp.match(lineEdit->objectName()).captured("ID").toInt());
        lineEdit->setValidator(new QRegularExpressionValidator(QRegularExpression(QStringLiteral("[0-9a-f]{0,4}"),
            QRegularExpression::CaseInsensitiveOption), this));
        connect(lineEdit, &QLineEdit::textChanged, this, &modbus::setRegister);
    }
}

 将例子中的mainwindow.ui修改成modbus.ui，里面的内容无需修改。

5.增加资源文件

 

 复制图示中的文件到新的项目文件夹里面，然后添加资源

 

 6.对话框文件直接复制，无需修改

7.运行

运行后就是第二步中的样子 ，这个通过这个例子可以直接连接Modbus设置，增加相关函数，可以在其他cpp文件中直接调用。即能调试，也方便开发，省了不少事情。

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