diff --git a/src/atcore.h b/src/atcore.h
--- a/src/atcore.h
+++ b/src/atcore.h
@@ -59,6 +59,8 @@
     Q_PROPERTY(QStringList portSpeeds READ portSpeeds)
     Q_PROPERTY(QString connectedPort READ connectedPort)
     Q_PROPERTY(AtCore::STATES state READ state WRITE setState NOTIFY stateChanged)
+    Q_PROPERTY(bool sdMount READ isSdMounted NOTIFY sdMountChanged)
+    Q_PROPERTY(QStringList sdFileList READ sdFileList NOTIFY sdCardFileListChanged)
 public:
     /**
      * @brief STATES enum Possible states the printer can be in
@@ -200,6 +202,18 @@
     */
     quint16 serialTimerInterval() const;
 
+    /**
+     * @brief Attempt to Mount an sd card
+     * @param slot: Sd card Slot on machine (0 is default)
+     */
+    void mountSd(int slot = 0);
+
+    /**
+     * @brief Attempt to Unmount an sd card
+     * @param slot: Sd card Slot on machine (0 is default)
+     */
+    void umountSd(int slot = 0);
+
 signals:
 
     /**
@@ -227,6 +241,16 @@
      */
     void portsChanged(QStringList);
 
+    /**
+     * @brief Sd Card Mount Changed
+     */
+    void sdMountChanged(bool);
+
+    /**
+     * @brief get a list of the files on the sd card
+     */
+    void sdCardFileListChanged(QStringList);
+
 public slots:
 
     /**
@@ -246,8 +270,9 @@
     /**
      * @brief Public Interface for printing a file
      * @param fileName: the gcode file to print.
+     * @param sdPrint: set true to print fileName from Sd card
      */
-    void print(const QString &fileName);
+    void print(const QString &fileName, bool sdPrint);
 
     /**
      * @brief Stop the Printer by empting the queue and aborting the print job (if running)
@@ -266,6 +291,7 @@
      *
      * Sends M114 on pause to store the location where the head stoped.
      * This is known to cause problems on fake printers
+     * Post Pause moves are not sent for sd card jobs firmware has it own post pause moves
      * @param pauseActions: Gcode to run after pausing commands are ',' separated
      * @sa resume(),stop(),emergencyStop()
      */
@@ -378,6 +404,23 @@
      */
     void setSerialTimerInterval(const quint16 &newTime);
 
+    /**
+     * @brief sdFileList
+     * @return List of files on the sd card.
+     */
+    QStringList sdFileList();
+
+    /**
+     * @brief Check if an sd card is mounted on the printer
+     * @return True if card mounted
+     */
+    bool isSdMounted();
+
+    /**
+     * @brief delete file from sd card
+     */
+    void sdDelete(const QString &fileName);
+
 private slots:
     /**
      * @brief processQueue send commands from the queue.
@@ -407,6 +450,11 @@
      */
     void locateSerialPort();
 
+    /**
+     * @brief Send request to the printer for the sd card file list.
+     */
+    void getSDFileList();
+
 private:
     /**
      * @brief True if a firmware plugin is loaded
diff --git a/src/atcore.cpp b/src/atcore.cpp
--- a/src/atcore.cpp
+++ b/src/atcore.cpp
@@ -61,6 +61,11 @@
     AtCore::STATES printerState;        //!< @param printerState: State of the Printer
     QStringList serialPorts;            //!< @param seralPorts: Detected serial Ports
     QTimer *serialTimer = nullptr;      //!< @param serialTimer: Timer connected to locateSerialPorts
+    bool sdCardMounted = false;         //!< @param sdCardMounted: True if Sd Card is mounted.
+    bool sdCardReadingFileList = false; //!< @param sdCardReadingFileList: True while getting file names from sd card
+    QString sdCardFileName;             //!< @param sdCardFileName: name of file being used from sd card.
+    bool sdCardPrinting = false;        //!< @param sdCardPrinting: True if currently printing from sd card.
+    QStringList sdCardFileList;         //!< @param sdCardFileList: List of files on sd card.
 };
 
 AtCore::AtCore(QObject *parent) :
@@ -297,15 +302,40 @@
 void AtCore::newMessage(const QByteArray &message)
 {
     d->lastMessage = message;
-    if (message.startsWith(QString::fromLatin1("X:").toLocal8Bit())) {
-        d->posString = message;
-        d->posString.resize(d->posString.indexOf('E'));
-        d->posString.replace(':', "");
-    }
 
-    //Check if have temperature info and decode it
-    if (d->lastMessage.contains("T:") || d->lastMessage.contains("B:")) {
-        temperature().decodeTemp(message);
+    if (message.contains("End file list")) {
+        d->sdCardReadingFileList = false;
+        emit(sdCardFileListChanged(d->sdCardFileList));
+    } else if (d->sdCardReadingFileList) {
+        // Below is to not add directories
+        if (!message.endsWith('/')) {
+            QString fileName = QString::fromLocal8Bit(message);
+            fileName.chop(fileName.length() - fileName.lastIndexOf(QChar::fromLatin1(' ')));
+            d->sdCardFileList.append(fileName);
+            qCDebug(ATCORE_CORE) << "Adding " << fileName << " to file list";
+        }
+    } else {
+        if (message.startsWith(QString::fromLatin1("X:").toLocal8Bit())) {
+            d->posString = message;
+            d->posString.resize(d->posString.indexOf('E'));
+            d->posString.replace(':', "");
+        } else if (message.contains("SD card")) {
+            if (message.contains("inserted")) {
+                d->sdCardMounted = true;
+            } else if (message.contains("removed")) {
+                d->sdCardMounted = false;
+            }
+            emit sdMountChanged(d->sdCardMounted);
+        } else if (message.contains("Begin file list")) {
+            if (d->sdCardMounted != true) {
+                d->sdCardMounted = true;
+                emit sdMountChanged(true);
+            }
+            d->sdCardReadingFileList = true;
+            d->sdCardFileList.clear();
+        } else if (d->lastMessage.contains("T:") || d->lastMessage.contains("B:")) {
+            temperature().decodeTemp(message);
+        }
     }
     emit(receivedMessage(d->lastMessage));
 }
@@ -322,27 +352,43 @@
 
 float AtCore::percentagePrinted() const
 {
+    /*
+        if(d->sdCardPrinting) {
+            pushCommand(GCode::toCommand(GCode::M27));
+        } else {
+            return d->percentage;
+        }
+    */
     return d->percentage;
 }
 
-void AtCore::print(const QString &fileName)
+void AtCore::print(const QString &fileName, bool sdPrint)
 {
-    if (state() == AtCore::CONNECTING) {
-        qCDebug(ATCORE_CORE) << "Load a firmware plugin to print.";
-        return;
-    }
-    //START A THREAD AND CONNECT TO IT
-    setState(AtCore::STARTPRINT);
-    QThread *thread = new QThread();
-    PrintThread *printThread = new PrintThread(this, fileName);
-    printThread->moveToThread(thread);
-
-    connect(printThread, &PrintThread::printProgressChanged, this, &AtCore::printProgressChanged, Qt::QueuedConnection);
-    connect(thread, &QThread::started, printThread, &PrintThread::start);
-    connect(printThread, &PrintThread::finished, thread, &QThread::quit);
-    connect(thread, &QThread::finished, printThread, &PrintThread::deleteLater);
-    if (!thread->isRunning()) {
-        thread->start();
+    if (sdPrint) {
+        pushCommand(GCode::toCommand(GCode::M23, fileName));
+        d->sdCardFileName = fileName;
+        pushCommand(GCode::toCommand(GCode::M24));
+        setState(AtCore::STARTPRINT);
+        setState(AtCore::BUSY);
+        d->sdCardPrinting = true;
+    } else {
+        if (state() == AtCore::CONNECTING) {
+            qCDebug(ATCORE_CORE) << "Load a firmware plugin to print.";
+            return;
+        }
+        //START A THREAD AND CONNECT TO IT
+        setState(AtCore::STARTPRINT);
+        QThread *thread = new QThread();
+        PrintThread *printThread = new PrintThread(this, fileName);
+        printThread->moveToThread(thread);
+
+        connect(printThread, &PrintThread::printProgressChanged, this, &AtCore::printProgressChanged, Qt::QueuedConnection);
+        connect(thread, &QThread::started, printThread, &PrintThread::start);
+        connect(printThread, &PrintThread::finished, thread, &QThread::quit);
+        connect(thread, &QThread::finished, printThread, &PrintThread::deleteLater);
+        if (!thread->isRunning()) {
+            thread->start();
+        }
     }
 }
 
@@ -391,8 +437,14 @@
 void AtCore::stop()
 {
     setState(AtCore::STOP);
-    d->commandQueue.clear();
+    if (d->sdCardPrinting) {
+        pushCommand(GCode::toCommand(GCode::M25));
+        d->sdCardFileName = QStringLiteral("");
+        pushCommand(GCode::toCommand(GCode::M23, d->sdCardFileName));
+        d->sdCardPrinting = false;
+    }
     setExtruderTemp(0, 0);
+    d->commandQueue.clear();
     setBedTemp(0);
     home(AtCore::X);
 }
@@ -403,6 +455,9 @@
         setState(AtCore::STOP);
     }
     d->commandQueue.clear();
+    if (d->sdCardPrinting) {
+        stop();
+    }
     serial()->pushCommand(GCode::toCommand(GCode::M112).toLocal8Bit());
 }
 
@@ -468,19 +523,27 @@
 
 void AtCore::pause(const QString &pauseActions)
 {
-    pushCommand(GCode::toCommand(GCode::M114));
-    setState(AtCore::PAUSE);
-    if (!pauseActions.isEmpty()) {
-        QStringList temp = pauseActions.split(QChar::fromLatin1(','));
-        for (int i = 0; i < temp.length(); i++) {
-            pushCommand(temp.at(i));
+    if (d->sdCardPrinting) {
+        pushCommand(GCode::toCommand(GCode::M25));
+    } else {
+        pushCommand(GCode::toCommand(GCode::M114));
+        if (!pauseActions.isEmpty()) {
+            QStringList temp = pauseActions.split(QChar::fromLatin1(','));
+            for (int i = 0; i < temp.length(); i++) {
+                pushCommand(temp.at(i));
+            }
         }
     }
+    setState(AtCore::PAUSE);
 }
 
 void AtCore::resume()
 {
-    pushCommand(GCode::toCommand(GCode::G0, QString::fromLatin1(d->posString)));
+    if (d->sdCardPrinting) {
+        pushCommand(GCode::toCommand(GCode::M24));
+    } else {
+        pushCommand(GCode::toCommand(GCode::G0, QString::fromLatin1(d->posString)));
+    }
     setState(AtCore::BUSY);
 }
 
@@ -624,3 +687,37 @@
         pushCommand(GCode::toCommand(GCode::M84));
     }
 }
+
+bool AtCore::isSdMounted()
+{
+    return d->sdCardMounted;
+}
+
+void AtCore::getSDFileList()
+{
+    pushCommand(GCode::toCommand(GCode::M20));
+}
+
+QStringList AtCore::sdFileList()
+{
+    if (d->sdCardFileList.isEmpty()) {
+        getSDFileList();
+    }
+    return d->sdCardFileList;
+}
+
+void AtCore::sdDelete(const QString &fileName)
+{
+    pushCommand(GCode::toCommand(GCode::M30, fileName));
+    getSDFileList();
+}
+
+void AtCore::mountSd(int slot)
+{
+    pushCommand(GCode::toCommand(GCode::M21, QString::number(slot)));
+}
+
+void AtCore::umountSd(int slot)
+{
+    pushCommand(GCode::toCommand(GCode::M22, QString::number(slot)));
+}
diff --git a/src/gcodecommands.cpp b/src/gcodecommands.cpp
--- a/src/gcodecommands.cpp
+++ b/src/gcodecommands.cpp
@@ -139,7 +139,7 @@
         return QObject::tr("M21: Initialize SDCard");
     case M22://Teacup - Sprinter - Marlin - Repetier - RepRap Firmware
         return QObject::tr("M22: Release SDCard");
-    case M23:////Teacup - Sprinter - Marlin - Repetier - Smoothie - RepRap Firmware
+    case M23://Teacup - Sprinter - Marlin - Repetier - Smoothie - RepRap Firmware
         return QObject::tr("M23: Select SD file");
     case M24://Teacup - Sprinter - Marlin - Repetier - Smoothie - RepRap Firmware
         return QObject::tr("M24: Start/resume SD print");
@@ -299,7 +299,7 @@
         return QObject::tr("M231: Set OPS parameter");
     case M232://Repetier
         return QObject::tr("M232: Read and reset max. advance values");
-    case M240: //Marlin
+    case M240://Marlin
         return QObject::tr("M240: Trigger camera");
     case M250://Marlin
         return QObject::tr("M250: Set LCD contrast");
@@ -504,6 +504,67 @@
 QString GCode::toCommand(MCommands gcode, const QString &value1, const QString &value2)
 {
     switch (gcode) {
+    case M20: {
+        return QStringLiteral("M20");
+    }
+    case M21: {
+        if (!value1.isEmpty()) {
+            return QStringLiteral("M21 P%1").arg(value1);
+        }
+        return QStringLiteral("M21");
+    }
+    case M22: {
+        if (!value1.isEmpty()) {
+            return QStringLiteral("M22 P%1").arg(value1);
+        }
+        return QStringLiteral("M22");
+    }
+    case M23: {
+        if (!value1.isEmpty()) {
+            return QStringLiteral("M23 %1").arg(value1);
+        }
+        return QObject::tr("ERROR! M23: It's obligatory to have an argument");
+    }
+    case M24: {
+        return QStringLiteral("M24");
+    }
+    case M25: {
+        return QStringLiteral("M25");
+    }
+    /// For M26 values that end with %. AtCore will send the percentage verison of the command (optional in firmwares)
+    /// For all values not ending in % it will start on that byte. This is the standard Sd resume supported by all reprap based firmware.
+    case M26: {
+        if (!value1.isEmpty()) {
+            if (value1.endsWith(QStringLiteral("%"))) {
+                QString temp = value1;
+                temp.replace(QStringLiteral("%"), QStringLiteral(""));
+                return QStringLiteral("M26 P%1").arg(temp.toDouble() / 100);
+            }
+            return QStringLiteral("M26 S%1").arg(value1);
+        }
+        return QObject::tr("ERROR! M26: It's obligatory to have an argument");
+    }
+    case M27: {
+        return QStringLiteral("M27");
+    }
+    case M28: {
+        if (!value1.isEmpty()) {
+            return QStringLiteral("M28 %1").arg(value1);
+        }
+        return QObject::tr("ERROR! M28: It's obligatory to have an argument");
+    }
+    case M29: {
+        if (!value1.isEmpty()) {
+            return QStringLiteral("M29 %1").arg(value1);
+        }
+        return QObject::tr("ERROR! M29: It's obligatory to have an argument");
+    }
+    case M30: {
+        if (!value1.isEmpty()) {
+            return QStringLiteral("M30 %1").arg(value1);
+        }
+        return QObject::tr("ERROR! M30: It's obligatory to have an argument");
+    }
     case M84: {
         if (!value1.isEmpty()) {
             return QStringLiteral("M84 S%1").arg(value1);
diff --git a/testclient/mainwindow.h b/testclient/mainwindow.h
--- a/testclient/mainwindow.h
+++ b/testclient/mainwindow.h
@@ -131,6 +131,10 @@
      */
     void printPBClicked();
 
+    /**
+     * @brief Print Button for Sd Prints clicked.
+     */
+    void pb_printSDClicked();
     /**
      * @brief Save the log file.
      */
@@ -176,12 +180,24 @@
      * @brief Show the about dialog
      */
     void about();
+
+    /**
+     * @brief List Files on the sd card.
+     */
+    void getSdList();
+
+    /**
+     * @brief Sd Card Delete file clicked
+     */
+    void pb_sdDelClicked();
+
 signals:
     /**
      * @brief printFile emit ready to print a file to atcore
      * @param fileName : the file to print
+     * @param sdPrint : True if file is on printers Sd Card
      */
-    void printFile(const QString &fileName);
+    void printFile(const QString &fileName, bool sdPrint = false);
 
 private:
     Ui::MainWindow *ui;
@@ -269,4 +285,9 @@
      * @brief Populate comboboxes
      */
     void populateCBs();
+
+    /**
+     * @brief Gui Changes for when sd card mount status has changed.
+     */
+    void sdChanged(bool mounted);
 };
diff --git a/testclient/mainwindow.cpp b/testclient/mainwindow.cpp
--- a/testclient/mainwindow.cpp
+++ b/testclient/mainwindow.cpp
@@ -90,18 +90,27 @@
     connect(ui->mvAxisPB, &QPushButton::clicked, this, &MainWindow::mvAxisPBClicked);
     connect(ui->fanSpeedPB, &QPushButton::clicked, this, &MainWindow::fanSpeedPBClicked);
     connect(ui->printPB, &QPushButton::clicked, this, &MainWindow::printPBClicked);
+    connect(ui->pb_printSD, &QPushButton::clicked, this, &MainWindow::pb_printSDClicked);
+    connect(ui->pb_sdDel, &QPushButton::clicked, this, &MainWindow::pb_sdDelClicked);
     connect(ui->printerSpeedPB, &QPushButton::clicked, this, &MainWindow::printerSpeedPBClicked);
     connect(ui->flowRatePB, &QPushButton::clicked, this, &MainWindow::flowRatePBClicked);
     connect(ui->showMessagePB, &QPushButton::clicked, this, &MainWindow::showMessage);
     connect(ui->pluginCB, &QComboBox::currentTextChanged, this, &MainWindow::pluginCBChanged);
     connect(ui->disableMotorsPB, &QPushButton::clicked, this, &MainWindow::disableMotorsPBClicked);
+    connect(ui->pb_sdList, &QPushButton::clicked, this, &MainWindow::getSdList);
     connect(core, &AtCore::stateChanged, this, &MainWindow::printerStateChanged);
     connect(this, &MainWindow::printFile, core, &AtCore::print);
     connect(ui->stopPB, &QPushButton::clicked, core, &AtCore::stop);
     connect(ui->emergencyStopPB, &QPushButton::clicked, core, &AtCore::emergencyStop);
     connect(axisControl, &AxisControl::clicked, this, &MainWindow::axisControlClicked);
     connect(core, &AtCore::portsChanged, this, &MainWindow::locateSerialPort);
     connect(core, &AtCore::printProgressChanged, this, &MainWindow::printProgressChanged);
+    connect(core, &AtCore::sdMountChanged, this, &MainWindow::sdChanged);
+
+    connect(core, &AtCore::sdCardFileListChanged, [this](QStringList fileList) {
+        ui->list_sdFileView->clear();
+        ui->list_sdFileView->addItems(fileList);
+    });
 
     connect(&core->temperature(), &Temperature::bedTemperatureChanged, [ = ](float temp) {
         checkTemperature(0x00, 0, temp);
@@ -135,11 +144,13 @@
     ui->menuView->insertAction(nullptr, ui->moveDock->toggleViewAction());
     ui->menuView->insertAction(nullptr, ui->tempTimelineDock->toggleViewAction());
     ui->menuView->insertAction(nullptr, ui->logDock->toggleViewAction());
+    ui->menuView->insertAction(nullptr, ui->sdDock->toggleViewAction());
 
     //more dock stuff.
     setTabPosition(Qt::LeftDockWidgetArea, QTabWidget::North);
     setTabPosition(Qt::RightDockWidgetArea, QTabWidget::North);
     tabifyDockWidget(ui->moveDock, ui->tempControlsDock);
+    tabifyDockWidget(ui->moveDock, ui->sdDock);
     ui->moveDock->raise();
 
     tabifyDockWidget(ui->connectDock, ui->printDock);
@@ -487,14 +498,16 @@
         ui->moveDock->setDisabled(true);
         ui->tempControlsDock->setDisabled(true);
         ui->printDock->setDisabled(true);
+        ui->sdDock->setDisabled(true);
         break;
 
     case AtCore::CONNECTING:
         stateString = QStringLiteral("Connecting");
         ui->commandDock->setDisabled(false);
         ui->moveDock->setDisabled(false);
         ui->tempControlsDock->setDisabled(false);
         ui->printDock->setDisabled(false);
+        ui->sdDock->setDisabled(false);
         break;
 
     case AtCore::STOP:
@@ -552,14 +565,16 @@
         delete ui->moveDock->titleBarWidget();
         delete ui->tempControlsDock->titleBarWidget();
         delete ui->printDock->titleBarWidget();
+        delete ui->sdDock->titleBarWidget();
     } else {
         ui->connectDock->setTitleBarWidget(new QWidget());
         ui->logDock->setTitleBarWidget(new QWidget());
         ui->tempTimelineDock->setTitleBarWidget(new QWidget());
         ui->commandDock->setTitleBarWidget(new QWidget());
         ui->moveDock->setTitleBarWidget(new QWidget());
         ui->tempControlsDock->setTitleBarWidget(new QWidget());
         ui->printDock->setTitleBarWidget(new QWidget());
+        ui->sdDock->setTitleBarWidget(new QWidget());
     }
 }
 
@@ -580,3 +595,36 @@
 {
     core->setIdleHold(0);
 }
+
+void MainWindow::sdChanged(bool mounted)
+{
+    if (mounted) {
+        ui->lbl_sd->setText(QStringLiteral("SD"));
+    } else {
+        ui->lbl_sd->setText(QStringLiteral(""));
+    }
+}
+
+void MainWindow::getSdList()
+{
+    core->sdFileList();
+}
+
+void MainWindow::pb_printSDClicked()
+{
+    if (ui->list_sdFileView->currentRow() == -1) {
+        QMessageBox::information(this, QStringLiteral("Print Error"), QStringLiteral("You must Select a file from the list"));
+    } else  {
+        core->print(ui->list_sdFileView->currentItem()->text(), true);
+    }
+}
+
+void MainWindow::pb_sdDelClicked()
+{
+    if (ui->list_sdFileView->currentRow() == -1) {
+        QMessageBox::information(this, QStringLiteral("Print Error"), QStringLiteral("You must Select a file from the list"));
+    } else  {
+        core->sdDelete(ui->list_sdFileView->currentItem()->text());
+        ui->list_sdFileView->setCurrentRow(-1);
+    }
+}
diff --git a/testclient/mainwindow.ui b/testclient/mainwindow.ui
--- a/testclient/mainwindow.ui
+++ b/testclient/mainwindow.ui
@@ -56,6 +56,41 @@
        </property>
       </widget>
      </item>
+     <item>
+      <spacer name="horizontalSpacer_2">
+       <property name="orientation">
+        <enum>Qt::Horizontal</enum>
+       </property>
+       <property name="sizeType">
+        <enum>QSizePolicy::Fixed</enum>
+       </property>
+       <property name="sizeHint" stdset="0">
+        <size>
+         <width>10</width>
+         <height>20</height>
+        </size>
+       </property>
+      </spacer>
+     </item>
+     <item>
+      <widget class="QFrame" name="frame">
+       <property name="frameShape">
+        <enum>QFrame::StyledPanel</enum>
+       </property>
+       <property name="frameShadow">
+        <enum>QFrame::Raised</enum>
+       </property>
+       <layout class="QHBoxLayout" name="horizontalLayout_14">
+        <item>
+         <widget class="QLabel" name="lbl_sd">
+          <property name="text">
+           <string/>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </widget>
+     </item>
      <item>
       <spacer name="horizontalSpacer">
        <property name="orientation">
@@ -380,6 +415,71 @@
      </layout>
     </widget>
    </widget>
+   <widget class="QDockWidget" name="sdDock">
+    <property name="enabled">
+     <bool>false</bool>
+    </property>
+    <property name="geometry">
+     <rect>
+      <x>0</x>
+      <y>42</y>
+      <width>515</width>
+      <height>317</height>
+     </rect>
+    </property>
+    <property name="windowTitle">
+     <string>S&amp;d Card</string>
+    </property>
+    <widget class="QWidget" name="dockWidgetContents_5">
+     <layout class="QVBoxLayout" name="verticalLayout_3">
+      <item>
+       <widget class="QFrame" name="frame_2">
+        <property name="frameShape">
+         <enum>QFrame::StyledPanel</enum>
+        </property>
+        <property name="frameShadow">
+         <enum>QFrame::Raised</enum>
+        </property>
+        <layout class="QHBoxLayout" name="horizontalLayout_18">
+         <item>
+          <widget class="QPushButton" name="pb_sdList">
+           <property name="text">
+            <string>Get List</string>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QPushButton" name="pb_printSD">
+           <property name="text">
+            <string>Print Selected</string>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QPushButton" name="pb_sdDel">
+           <property name="text">
+            <string>Delete Selected</string>
+           </property>
+          </widget>
+         </item>
+        </layout>
+       </widget>
+      </item>
+      <item>
+       <widget class="QGroupBox" name="groupBox_3">
+        <property name="title">
+         <string>Files On Sd Card.</string>
+        </property>
+        <layout class="QVBoxLayout" name="verticalLayout_11">
+         <item>
+          <widget class="QListWidget" name="list_sdFileView"/>
+         </item>
+        </layout>
+       </widget>
+      </item>
+     </layout>
+    </widget>
+   </widget>
   </widget>
   <widget class="QDockWidget" name="tempTimelineDock">
    <property name="minimumSize">
diff --git a/unittests/gcodetests.h b/unittests/gcodetests.h
--- a/unittests/gcodetests.h
+++ b/unittests/gcodetests.h
@@ -59,6 +59,17 @@
     void string_G161();
     void string_G162();
 
+    void command_M20();
+    void command_M21();
+    void command_M22();
+    void command_M23();
+    void command_M24();
+    void command_M25();
+    void command_M26();
+    void command_M27();
+    void command_M28();
+    void command_M29();
+    void command_M30();
     void command_M84();
     void command_M104();
     void command_M105();
diff --git a/unittests/gcodetests.cpp b/unittests/gcodetests.cpp
--- a/unittests/gcodetests.cpp
+++ b/unittests/gcodetests.cpp
@@ -183,6 +183,70 @@
     QVERIFY(GCode::toString(GCode::G162) == QObject::tr("G162: Home axis to maximum"));
 }
 
+void GCodeTests::command_M20()
+{
+    QVERIFY(GCode::toCommand(GCode::M20) == QStringLiteral("M20"));
+}
+
+void GCodeTests::command_M21()
+{
+    QVERIFY(GCode::toCommand(GCode::M21) == QStringLiteral("M21"));
+    QVERIFY(GCode::toCommand(GCode::M21, QStringLiteral("2")) == QStringLiteral("M21 P2"));
+}
+
+void GCodeTests::command_M22()
+{
+    QVERIFY(GCode::toCommand(GCode::M22) == QStringLiteral("M22"));
+    QVERIFY(GCode::toCommand(GCode::M22, QStringLiteral("5")) == QStringLiteral("M22 P5"));
+}
+
+void GCodeTests::command_M23()
+{
+    QVERIFY(GCode::toCommand(GCode::M23) == QStringLiteral("ERROR! M23: It's obligatory to have an argument"));
+    QVERIFY(GCode::toCommand(GCode::M23, QStringLiteral("FileName")) == QStringLiteral("M23 FileName"));
+}
+
+void GCodeTests::command_M24()
+{
+    QVERIFY(GCode::toCommand(GCode::M24) == QStringLiteral("M24"));
+}
+
+void GCodeTests::command_M25()
+{
+    QVERIFY(GCode::toCommand(GCode::M25) == QStringLiteral("M25"));
+}
+
+void GCodeTests::command_M26()
+{
+    QVERIFY(GCode::toCommand(GCode::M26) == QStringLiteral("ERROR! M26: It's obligatory to have an argument"));
+    QVERIFY(GCode::toCommand(GCode::M26, QStringLiteral("15%")) == QStringLiteral("M26 P0.15"));
+    QVERIFY(GCode::toCommand(GCode::M26, QStringLiteral("15")) == QStringLiteral("M26 S15"));
+
+}
+
+void GCodeTests::command_M27()
+{
+    QVERIFY(GCode::toCommand(GCode::M27) == QStringLiteral("M27"));
+}
+
+void GCodeTests::command_M28()
+{
+    QVERIFY(GCode::toCommand(GCode::M28) == QStringLiteral("ERROR! M28: It's obligatory to have an argument"));
+    QVERIFY(GCode::toCommand(GCode::M28, QStringLiteral("FileName")) == QStringLiteral("M28 FileName"));
+}
+
+void GCodeTests::command_M29()
+{
+    QVERIFY(GCode::toCommand(GCode::M29) == QStringLiteral("ERROR! M29: It's obligatory to have an argument"));
+    QVERIFY(GCode::toCommand(GCode::M29, QStringLiteral("FileName")) == QStringLiteral("M29 FileName"));
+}
+
+void GCodeTests::command_M30()
+{
+    QVERIFY(GCode::toCommand(GCode::M30) == QStringLiteral("ERROR! M30: It's obligatory to have an argument"));
+    QVERIFY(GCode::toCommand(GCode::M30, QStringLiteral("FileName")) == QStringLiteral("M30 FileName"));
+}
+
 void GCodeTests::command_M84()
 {
     QVERIFY(GCode::toCommand(GCode::M84) == QStringLiteral("M84"));