使用 CAN 为 Simulink 模型开发 App

function getAvailableCANChannelInfo(app)
    % Get a table containing all available CAN channels and devices.
    app.canChannelInfo = canChannelList;
    
    % Format CAN channel information for display on the UI.
    app.availableCANChannelsForDisplay = formatCANChannelEntryForDisplay(app);
    
    % Save the number of available constructors.
    app.numConstructors = numel(app.canChannelInfo.Vendor);
end

function canChannelConstructor = formatCANChannelConstructor(app, index)
    canChannelConstructor = "canChannel(" + "'" + app.canChannelInfo.Vendor(index) + "'" + ", " + "'" + app.canChannelInfo.Device(index) + "'" + ", " + app.canChannelInfo.Channel(index) + ")";
end

function setupCANChannel(app)
    % Open CAN database file.
    db = canDatabase('CruiseControl.dbc');
    
    % Create a CAN channel for sending and receiving messages.
    app.canChannelObj = eval(app.canChannelConstructorSelected);
    
    % Attach CAN database to channel for received message decoding.
    app.canChannelObj.Database = db;
    
    % Set the baud rate (can only do this if the UI has channel initialization access).
    if app.canChannelObj.InitializationAccess
        configBusSpeed(app.canChannelObj, 500000);
    end
end 

function setupCANTransmitMessages(app)
    % Create a CAN message container.
    app.cruiseControlCmdMessage = canMessage(app.canChannelObj.Database, 'CruiseCtrlCmd');
    
    % Fill the message container with signals and assign values to each signal.
    app.cruiseControlCmdMessage.Signals.S01_CruiseOnOff = logical2Numeric(app, app.cruisePowerCheckBox.Value);
    app.cruiseControlCmdMessage.Signals.S02_Brake =  logical2Numeric(app, app.brakeOnOffCheckBox.Value);
    app.cruiseControlCmdMessage.Signals.S03_VehicleSpeed =  app.vehicleSpeedSlider.Value;
    app.cruiseControlCmdMessage.Signals.S04_CoastSetSw =  logical2Numeric(app, app.cruiseCoastSetCheckBox.Value);
    app.cruiseControlCmdMessage.Signals.S05_AccelResSw =  logical2Numeric(app, app.cruiseAccelResumeCheckBox.Value);
    
    % Set up periodic transmission of this CAN message.  Actual transmission starts/stops with CAN channel start/stop.
    transmitPeriodic(app.canChannelObj, app.cruiseControlCmdMessage, 'On', 0.1);
end

% create a timer to receive CAN msgs
app.receiveCANmsgsTimer = timer('Period', 0.5,...
    'ExecutionMode', 'fixedSpacing', ...
    'TimerFcn', @(~,~)receiveCANmsgsTimerCallback(app));

% receiveCANmsgsTimerCallback Timer callback function for GUI updating
function receiveCANmsgsTimerCallback(app)
    try
        % Receive available CAN messages.
        msg = receive(app.canChannelObj, Inf, 'OutputFormat', 'timetable');
        
        % Update Cruise Control Feedback CAN message data.
        newFbData = getCruiseCtrlFBCANmessage(app, msg);
        
        if ~newFbData
            return;
        end
        
        % Update target speed and engaged plots with latest data from CAN bus.
        updatePlots(app);
    catch err
        disp(err.message)
    end
end

function newFbData = getCruiseCtrlFBCANmessage(app, msg)
    % Exit if no messages were received as there is nothing to update.
    if isempty(msg)
        newFbData = false;
        return;
    end
    
    % Extract signals from all CruiseCtrlFB messages.
    cruiseCtrlFBSignals = canSignalTimetable(msg, "CruiseCtrlFB");
    
    % if no messages then just return as there is nothing to do
    if isempty(cruiseCtrlFBSignals)
        newFbData = false;
        return;
    end
    
    if ~isempty(cruiseCtrlFBSignals)
        % Received new Cruise Control Feedback messages, so create time series from CAN signal data
        % save the Target Speed feedback signal.
        if isempty(app.tspeedFb) % cCeck if target speed feedback property has been initialized.
            app.tspeedFb = cell(2,1);
            
            % It appears Simulink.SimulationData.Dataset class is not
            % compatible with MATLAB Compiler, so change the way we store data
            % from a Dataset format to cell array.
            
            % Save target speed actual data.
            app.tspeedFb = timeseries(cruiseCtrlFBSignals.F02_TargetSpeed, seconds(cruiseCtrlFBSignals.Time),...
                'Name','CruiseControlTargetSpeed');
        else  % Add to existing data.
            % Save target speed actual data.
            app.tspeedFb = timeseries([app.tspeedFb.Data; cruiseCtrlFBSignals.F02_TargetSpeed], ...
                [app.tspeedFb.Time; seconds(cruiseCtrlFBSignals.Time)],'Name','CruiseControlTargetSpeed');
        end
        
        % Save the Cruise Control Engaged actual signal.
        % Check if Cruise engaged property has been initialized.
        if isempty(app.engagedFb)    
            app.engagedFb = cell(2,1);

            % It appears Simulink.SimulationData.Dataset class is not
            % compatible with MATLAB Compiler, so change the way we store data
            % from a Dataset format to cell array.
            
            % Save cruise engaged command data.
            app.engagedFb = timeseries(cruiseCtrlFBSignals.F01_Engaged,seconds(cruiseCtrlFBSignals.Time),...
                'Name','CruiseControlEngaged');
        else  % Add to existing logsout.
            % Save cruise engaged command data.
            app.engagedFb = timeseries([app.engagedFb.Data; cruiseCtrlFBSignals.F01_Engaged], ...
                [app.engagedFb.Time; seconds(cruiseCtrlFBSignals.Time)],'Name','CruiseControlEngaged');
        end
        
        newFbData = true;
    end
end

function startSimApplication(app, index)
    % Start the model running on the desktop.
    
    % Check to see if hardware or virtual CAN channel is selected, otherwise do nothing.
    if app.canChannelInfo.DeviceModel(index) == "Virtual"
        % Check to see if the model is loaded before trying to run.
        if bdIsLoaded(app.mdl)
            % Model is loaded, now check to see if it is already running.
            if ~strcmp('running',get_param(app.mdl,'SimulationStatus'))
                % Model is not already running, so start it
                % flush the CAN Receive message buffers.
                app.tspeedFb = [];
                app.engagedFb = [];
                
                % Clear figure window.
                cla(app.tspeedPlot)
                cla(app.engagedPlot)
                
                % Start the CAN channels and update timer if it isn't already running.
                startCANChannel(app);
                
                % Start the model.
                set_param(app.mdl, 'SimulationCommand', 'start');
                
                % Set the sim start/stop button icon to the stop icon indicating the model has
                % been successfully started and is ready to be stopped at the next button press.
                app.SimStartStopButton.Icon = "IconEnd.png";
                app.StartSimLabel.Text = "Stop Sim";
            else
                % Model is already running, inform the user.
                warnStr = sprintf('Warning: Model %s is already running', app.mdl);
                warndlg(warnStr, 'Warning');
            end
        else
            % Model is not yet loaded, so warn the user.
            warnStr = sprintf('Warning: Model %s is not loaded\nPlease load the model and try again', app.mdl);
            warndlg(warnStr, 'Warning');
        end
    end
end

function startCANChannel(app)
    % Start the CAN channel if it isn't already running.
    try
        if ~app.canChannelObj.Running
            start(app.canChannelObj);
        end
    catch
        % do nothing.
    end
    
    % Start the CAN receive processing timer - check to see if it is already running. This allows us to change CAN channels
    % with or without starting and stopping the model running on the real time target.
    if strcmpi(app.receiveCANmsgsTimer.Running, 'off')
        start(app.receiveCANmsgsTimer);
    end
end

function stopSimApplication(app, index)
    % Stop the model running on the desktop.
    try
        % Check to see if hardware or virtual CAN channel is selected.
        if app.canChannelInfo.DeviceModel(index) == "Virtual"
            % Virtual channel selected, so issue a stop command to the
            % the simulation, even if it is already stopped.
            set_param(app.mdl, 'SimulationCommand', 'stop')
            
            % Stop the CAN channels and update timer.
            stopCANChannel(app);
        end
        
        % Set the sim start/stop button text to Start indicating the model has
        % been successfully stopped and is ready to start again at the next
        % button press.
        app.SimStartStopButton.Icon = "IconPlay.png";
        app.StartSimLabel.Text = "Start Sim";
    catch
        % Do nothing at the moment.
    end
end

function stopCANChannel(app)
    % Stop the CAN channel.
    stop(app.canChannelObj);
    
    % Stop the CAN message processing timer.
    stop(app.receiveCANmsgsTimer);
end

function setupCANLogChannel(app)
    % Open CAN database file.
    db = canDatabase('CruiseControl.dbc');
    
    % Create a CAN channel for sending and receiving messages.
    app.canLogChannelObj = eval(app.canChannelConstructorSelected);
    
    % Attach CAN database to channel for received message decoding.
    app.canLogChannelObj.Database = db;
    
    % Set the baud rate (can only do this if the UI has channel initialization access).
    if app.canLogChannelObj.InitializationAccess
        configBusSpeed(app.canLogChannelObj, 500000);
    end
end

function startCANLogChannel(app)
    % Start the CAN Log channel if it isn't already running.
    try
        if ~app.canLogChannelObj.Running
            start(app.canLogChannelObj);
        end
    catch
        % Do nothing.
    end
end

function stopCANLogging(app)
    % Stop the CAN Log channel.
    stop(app.canLogChannelObj);
    
    % Get the messages from the CAN log message queue.
    retrieveLoggedCANMessages(app);
    
    % Update the button icon and label.
    app.canLoggingStartStopButton.Icon = 'IconPlay.png';
    app.StartLoggingLabel.Text = "Start Logging";
end

function retrieveLoggedCANMessages(app)
    try
        % Receive available CAN message
        % initialize buffer to make sure it is empty.
        app.canLogMsgBuffer = [];
        
        % Receive available CAN messages.
        msg = receive(app.canLogChannelObj, Inf, 'OutputFormat', 'timetable');
        
        % Fill the buffer with the logged Cruise Control Command CAN message data.
        app.canLogMsgBuffer = msg(msg.Name == "CruiseCtrlCmd", :);
    catch err
        disp(err.message)
    end
end

function savedLoggedCANDataToFile(app)
    % Raise dialog box to prompt user for a CAN log file to store the logged data.
    [FileName,PathName] = uiputfile('*.mat','Select a .MAT file to store logged CAN data');

    if FileName ~= 0
        % User did not cancel the file selection operation, so OK to save
        % convert the CAN log data from Timetable to struct of arrays so the data is compatible
        % with the VNT Simulink Replay block.
        canLogStructOfArrays = canMessageReplayBlockStruct(app.canLogMsgBuffer);
        save(fullfile(PathName, FileName), 'canLogStructOfArrays');

        % Clear the buffer after saving it.
        app.canLogMsgBuffer = [];
    end
end

function loadLoggedCANDataFromFile(app)
    % Raise dialog box to prompt user for a CAN log file to load.
    [FileName,PathName] = uigetfile('*.mat','Select a CAN log file to load');
    
    % Return focus to main UI after dlg closes.
    figure(app.UIFigure)
    
    if FileName ~= 0
        % User did not cancel the file selection operation, so OK to load
        % make sure the message buffer is empty before loading in the logged CAN data.
        app.canLogMsgBuffer = [];
        
        % Upload the saved message data from the selected file.
        canLogMsgStructOfArrays = load(fullfile(PathName, FileName), 'canLogStructOfArrays');
        
        % Convert the saved message data into timetables for the replay command.
        app.canLogMsgBuffer = canMessageTimetable(canLogMsgStructOfArrays.canLogStructOfArrays);
    end
end

function startPlaybackOfLoggedCANData(app)
    % Turn off periodic transmission of CruiseCtrlCmd CAN message from UI controls.
    transmitPeriodic(app.canChannelObj, app.cruiseControlCmdMessage, 'Off');
    
    % Stop the UI CAN channel so we can instead use if for playback.
    stopCANChannel(app)
    
    % Flush the existing CAN messages stored for plotting.
    flushCANFbMsgQueue(app)
    
    % Clear the existing plots.
    cla(app.tspeedPlot)
    cla(app.engagedPlot)
    
    % Start the CAN Channel and replay the logged CAN message data.
    startCANChannel(app)
    
    % Replay the logged CAN data on the UI CAN Channel.
    replay(app.canChannelObj, app.canLogMsgBuffer);
end

function stopPlaybackOfLoggedCANData(app)
    % Stop the playback CAN channel.
    stopCANChannel(app)
    
    % Flush the existing CAN messages stored for plotting.
    flushCANFbMsgQueue(app)
    
    % Clear the existing plots.
    cla(app.tspeedPlot)
    cla(app.engagedPlot)
    
    % Re-enable periodic transmission of CruiseCtrlCmd CAN message from UI controls.
    transmitPeriodic(app.canChannelObj, app.cruiseControlCmdMessage, 'On', 0.1);
    
    % Restart the CAN Channel from/To UI.
    startCANChannel(app)
end

function updateModelWithSelectedCANChannel(app, index)
    % Check to see if we are using a virtual CAN channel and whether the model is loaded.
    if app.canChannelInfo.DeviceModel(index) == "Virtual" && bdIsLoaded(app.mdl)
        % Using a virtual channel.
        
        % Find path to CAN configuration block.
        canConfigPath = find_system(app.mdl,'Variants', 'AllVariants', 'LookUnderMasks', 'all',...
            'FollowLInks', 'on', 'Name', 'CAN Configuration');
        
        % Find path to CAN transmit block.
        canTransmitPath = find_system(app.mdl,'Variants', 'AllVariants', 'LookUnderMasks', 'all',...
            'FollowLInks', 'on', 'Name', 'CAN Transmit');
        
        % Find path to CAN receive block.
        canReceivePath = find_system(app.mdl,'Variants', 'AllVariants', 'LookUnderMasks', 'all',...
            'FollowLInks', 'on', 'Name', 'CAN Receive');
        
        % Push the selected CAN channel into the simulation model CAN Configuration block.
        set_param(canConfigPath{1}, 'Device', app.canChannelDeviceSelected);
        set_param(canConfigPath{1}, 'DeviceMenu', app.canChannelDeviceSelected);
        set_param(canConfigPath{1}, 'ObjConstructor', app.canChannelConstructorSelected);
        
        % Push the selected CAN channel into the simulation model CAN Receive block.
        set_param(canReceivePath{1}, 'Device', app.canChannelDeviceSelected);
        set_param(canReceivePath{1}, 'DeviceMenu', app.canChannelDeviceSelected);
        set_param(canReceivePath{1}, 'ObjConstructor', app.canChannelConstructorSelected);
        
        % Push the selected CAN channel into the simulation model CAN Transmit block.
        set_param(canTransmitPath{1}, 'Device', app.canChannelDeviceSelected);
        set_param(canTransmitPath{1}, 'DeviceMenu', app.canChannelDeviceSelected);
        set_param(canTransmitPath{1}, 'ObjConstructor', app.canChannelConstructorSelected);
    end
end