plotandwriteemgleadoffdetectionexample.m

function shimmer = plotandwriteemgleadoffdetectionexample(comPort, captureDuration, fileName)
    %PLOTANDWRITEEMGLEADOFFDETECTIONEXAMPLE - Plotting ecg signal and lead-off detection bytes
    % and write to file
    %    INPUT: comPort  - String value defining the COM port number for Shimmer
    %   
    %    INPUT: captureDuration  - Numerical value defining the capture duration
    %
    %    INPUT: fileName - String value defining the name of the data file
    %
    %    OUTPUT: shimmer  - Object of the ShimmerHandleClass
    %
    % Example for Shimmer3
    addpath('./Resources/')                                                    % directory containing supporting functions


    %% definitions

    shimmer = ShimmerHandleClass(comPort);
    SensorMacros = SetEnabledSensorsMacrosClass;                               % assign user friendly macros for setenabledsensors

    fs = 512;                                                                  % sample rate in [Hz]
    firsttime = true;

    % Note: these constants are only relevant to this examplescript and are not used
    % by the ShimmerHandle Class
    NO_SAMPLES_IN_PLOT = 5000;                                                 % Number of samples in the plot 
    DELAY_PERIOD = 0.2;                                                        % Delay (in seconds) between data read operations
    numSamples = 0;

    %% settings

    % filtering settings
    fm = 50;                                                                   % mains frequency [Hz]
    fchp = 0.5;                                                                % corner frequency highpassfilter [Hz]; Shimmer recommends 0.5Hz for monitoring applications, 0.05Hz for diagnostic settings
    nPoles = 4;                                                                % number of poles (HPF, LPF)
    pbRipple = 0.5;                                                            % pass band ripple (%)
    
    HPF = true;                                                                % enable (true) or disable (false) highpass filter
    LPF = true;                                                                % enable (true) or disable (false) lowpass filter
    BSF = true;                                                                % enable (true) or disable (false) bandstop filter
    
    % highpass filters for ExG channels
    if (HPF)
        hpfexg1ch1 = FilterClass(FilterClass.HPF,fs,fchp,nPoles,pbRipple);
        hpfexg1ch2 = FilterClass(FilterClass.HPF,fs,fchp,nPoles,pbRipple);
    end
    % lowpass filters for ExG channels
    if (LPF)
        lpfexg1ch1 = FilterClass(FilterClass.LPF,fs,fs/2-1,nPoles,pbRipple);
        lpfexg1ch2 = FilterClass(FilterClass.LPF,fs,fs/2-1,nPoles,pbRipple);
    end
    % bandstop filters for ExG channels;
    % cornerfrequencies at +1Hz and -1Hz from mains frequency
    if (BSF)
        bsfexg1ch1 = FilterClass(FilterClass.LPF,fs,[fm-1,fm+1],nPoles,pbRipple);
        bsfexg1ch2 = FilterClass(FilterClass.LPF,fs,[fm-1,fm+1],nPoles,pbRipple);
    end
    

    
    %%
    if (shimmer.connect)
        shimmer.setsamplingrate(fs);                                           % Select sampling rate
        shimmer.setinternalboard('EMG');                                       % Select internal expansion board; select 'ECG' to enable both SENSOR_EXG1 and SENSOR_EXG2 
        shimmer.disableallsensors;                                             % Disable other sensors
        shimmer.setenabledsensors(SensorMacros.EMG,1);                         % Enable SENSOR_EXG1 and SENSOR_EXG2
        shimmer.setexgleadoffdetectionmode(1);                                 % Set ExG lead-off detection mode to 'DC Current'
        shimmer.setexgreferenceelectrodeconfiguration(3);                      % Set ExG reference electrode configuration to 'Inverse of Ch1'
        
        if (shimmer.start)                                                     % TRUE if the shimmer starts streaming 

            plotData = [];                                               
            timeStamp = [];
            filteredplotData = [];

            h.figure1=figure('Name','Shimmer EMG signals');                    % Create a handle to figure for plotting data from shimmer
            set(h.figure1, 'Position', [950, 600, 800, 400]);
            h.figure2=figure('Name','Shimmer Lead-off detection signals');     % Create a handle to figure for plotting data from shimmer
            set(h.figure2, 'Position', [100, 100, 800, 900]);
            h.figure3=figure('Name','Shimmer Lead-off detection signals');     % Create a handle to figure for plotting data from shimmer
            set(h.figure3, 'Position', [950, 100, 800, 400]);

            elapsedTime = 0;                                                   % Reset to 0    
            tic;                                                               % Start timer

            while (elapsedTime < captureDuration)       

                pause(DELAY_PERIOD);                                           % Pause for this period of time on each iteration to allow data to arrive in the buffer

                [newData,signalNameArray,signalFormatArray,signalUnitArray] = shimmer.getdata('a');   % Read the latest data from shimmer data buffer, signalFormatArray defines the format of the data and signalUnitArray the unit
                
                
                if (firsttime==true && isempty(newData)~=1)
                    firsttime = writeHeadersToFile(fileName,signalNameArray,signalFormatArray,signalUnitArray);
                end
                
                if ~isempty(newData)                                           % TRUE if new data has arrived
                    
                    chIndex(1) = find(ismember(signalNameArray, 'EMG CH1'));
                    chIndex(2) = find(ismember(signalNameArray, 'EMG CH2'));
                    chIndex(3) = find(ismember(signalNameArray,'EXG1 STA'));
                    chIndex(4) = find(ismember(signalNameArray,'EXG2 STA'));
                          
                    chIndex(5) = find(ismember(signalNameArray, 'Lead-off EMG CH1-Neg'));
                    chIndex(6) = find(ismember(signalNameArray, 'Lead-off EMG CH2-Pos'));
                    chIndex(7) = find(ismember(signalNameArray, 'Lead-off EMG CH2-Neg'));
                    chIndex(8) = find(ismember(signalNameArray,'Lead-off EMG Ref'));
                    chIndex(9) = find(ismember(signalNameArray,'Lead-off EMG CH1-Pos'));
                    
                    
                    
                    
                    EMGData = newData(:,chIndex);
                    EMGDataFiltered = EMGData;
                    % filter the data
                    if HPF % filter newData with highpassfilter to remove DC-offset
                        EMGDataFiltered(:,1) = hpfexg1ch1.filterData(EMGDataFiltered(:,1));
                        EMGDataFiltered(:,2) = hpfexg1ch2.filterData(EMGDataFiltered(:,2));
                    end
                    
                    if BSF % filter highpassfiltered data with bandstopfilter to suppress mains interference
                        EMGDataFiltered(:,1) = bsfexg1ch1.filterData(EMGDataFiltered(:,1));
                        EMGDataFiltered(:,2) = bsfexg1ch2.filterData(EMGDataFiltered(:,2));
                    end
                    
                    if LPF % filter bandstopfiltered data with lowpassfilter to avoid aliasing
                        EMGDataFiltered(:,1) = lpfexg1ch1.filterData(EMGDataFiltered(:,1));
                        EMGDataFiltered(:,2) = lpfexg1ch2.filterData(EMGDataFiltered(:,2));
                    end
                    
                    dlmwrite(fileName, newData, '-append', 'delimiter', '\t','precision',16); % Append the new data to the file in a tab delimited format

                    plotData = [plotData; EMGData];                            % Update the plotData buffer with the new ECG data
                    filteredplotData = [filteredplotData; EMGDataFiltered];    % Update the filteredplotData buffer with the new filtered ECG data
                    numPlotSamples = size(plotData,1);
                    numSamples = numSamples + size(newData,1);
                    timeStampIndex = find(ismember(signalNameArray,'Time Stamp'));
                    timeStampNew = newData(:,timeStampIndex(2));               % get timestamps
                    timeStamp = [timeStamp; timeStampNew];
                    if numSamples > NO_SAMPLES_IN_PLOT
                        plotData = plotData(numPlotSamples-NO_SAMPLES_IN_PLOT+1:end,:);
                        filteredplotData = filteredplotData(numPlotSamples-NO_SAMPLES_IN_PLOT+1:end,:);
                    end
                    sampleNumber = max(numSamples-NO_SAMPLES_IN_PLOT+1,1):numSamples;

                    set(0,'CurrentFigure',h.figure1);   
                    subplot(2,2,1);                                        % Create subplot
                    signalIndex = chIndex(1);
                    plot(sampleNumber,plotData(:,1));                      % Plot the emg for channel 1 of SENSOR_EXG1
                    legendName1=[signalFormatArray{signalIndex} ' ' signalNameArray{signalIndex} ' (' signalUnitArray{signalIndex} ')'];  
                    legend(legendName1);                                   % Add legend to plot
                    xlim([sampleNumber(1) sampleNumber(end)]);

                    subplot(2,2,2);                                        % Create subplot
                    signalIndex = chIndex(2);
                    plot(sampleNumber,plotData(:,2));                      % Plot the emg for channel 2 of SENSOR_EXG1
                    legendName1=[signalFormatArray{signalIndex} ' ' signalNameArray{signalIndex} ' (' signalUnitArray{signalIndex} ')'];  
                    legend(legendName1);                                   % Add legend to plot
                    xlim([sampleNumber(1) sampleNumber(end)]);

                    subplot(2,2,3);                                        % Create subplot
                    signalIndex = chIndex(1);
                    plot(sampleNumber,filteredplotData(:,1));              % Plot the filtered emg for channel 1 of SENSOR_EXG1
                    legendName1=[signalFormatArray{signalIndex} ' ' 'filtered' ' ' signalNameArray{signalIndex} ' (' signalUnitArray{signalIndex} ')'];  
                    legend(legendName1);                                   % Add legend to plot
                    xlim([sampleNumber(1) sampleNumber(end)]);

                    subplot(2,2,4);                                        % Create subplot
                    signalIndex = chIndex(2);
                    plot(sampleNumber,filteredplotData(:,2));              % Plot the filtered emg for channel 2 of SENSOR_EXG1
                    legendName1=[signalFormatArray{signalIndex} ' ' 'filtered' ' ' signalNameArray{signalIndex} ' (' signalUnitArray{signalIndex} ')'];  
                    legend(legendName1);                                   % Add legend to plot
                    xlim([sampleNumber(1) sampleNumber(end)]);
                              
                    
                    set(0,'CurrentFigure',h.figure2);   
                                    
                    subplot(5,1,1);                                        % Create subplot
                    signalIndex = chIndex(3);
                    plot(sampleNumber,plotData(:,3));                     % Plot 'EXG1 STA'
                    legendName1=[signalFormatArray{signalIndex} ' ' signalNameArray{signalIndex} ' (' signalUnitArray{signalIndex} ')'];
                    legend(legendName1, 'Location','West');                % Add legend to plot
                    xlim([sampleNumber(1) sampleNumber(end)]);
                    
                    subplot(5,1,2);                                        % Create subplot
                    signalIndex = chIndex(5);
                    plot(sampleNumber,plotData(:,5));                      % Plot 'Lead-off EMG CH1-Neg'
                    legendName1=[signalFormatArray{signalIndex} ' ' signalNameArray{signalIndex} ' (' signalUnitArray{signalIndex} ')'];  
                    legend(legendName1, 'Location','West');                % Add legend to plot
                    xlim([sampleNumber(1) sampleNumber(end)]);
                    ylim([-1 1]);
                    
                    subplot(5,1,3);                                        % Create subplot
                    signalIndex = chIndex(6);
                    plot(sampleNumber,plotData(:,6));                      % Plot 'Lead-off EMG CH2-Pos'
                    legendName1=[signalFormatArray{signalIndex} ' ' signalNameArray{signalIndex} ' (' signalUnitArray{signalIndex} ')'];  
                    legend(legendName1, 'Location','West');                % Add legend to plot
                    xlim([sampleNumber(1) sampleNumber(end)]);
                    ylim([-1 1]);

                    subplot(5,1,4);                                        % Create subplot
                    signalIndex = chIndex(7);
                    plot(sampleNumber,plotData(:,7));                      % Plot 'Lead-off EMG CH2-Neg'
                    legendName1=[signalFormatArray{signalIndex} ' ' signalNameArray{signalIndex} ' (' signalUnitArray{signalIndex} ')'];  
                    legend(legendName1, 'Location','West');                % Add legend to plot
                    xlim([sampleNumber(1) sampleNumber(end)]);
                    ylim([-1 1]);

                    subplot(5,1,5);                                        % Create subplot
                    signalIndex = chIndex(8);
                    plot(sampleNumber,plotData(:,8));                      % Plot 'Lead-off EMG Ref'
                    legendName1=[signalFormatArray{signalIndex} ' ' signalNameArray{signalIndex} ' (' signalUnitArray{signalIndex} ')'];  
                    legend(legendName1, 'Location','West');                % Add legend to plot
                    xlim([sampleNumber(1) sampleNumber(end)]);
                    ylim([-1 1]);
                    
                    set(0,'CurrentFigure',h.figure3);
                    
                    subplot(2,1,1);                                        % Create subplot
                    signalIndex = chIndex(4);
                    plot(sampleNumber,plotData(:,4));                     % Plot 'EXG2 STA'
                    legendName1=[signalFormatArray{signalIndex} ' ' signalNameArray{signalIndex} ' (' signalUnitArray{signalIndex} ')'];
                    legend(legendName1, 'Location','West');                % Add legend to plot
                    xlim([sampleNumber(1) sampleNumber(end)]);
                    
                    subplot(2,1,2);                                        % Create subplot
                    signalIndex = chIndex(9);
                    plot(sampleNumber,plotData(:,9));                      % Plot 'Lead-off EMG CH1-Pos'
                    legendName1=[signalFormatArray{signalIndex} ' ' signalNameArray{signalIndex} ' (' signalUnitArray{signalIndex} ')'];
                    legend(legendName1, 'Location','West');                % Add legend to plot
                    xlim([sampleNumber(1) sampleNumber(end)]);
                    ylim([-1 1]);
                end

                elapsedTime = elapsedTime + toc;                           % Update elapsedTime with the time that elapsed since starting the timer
                tic;                                                       % Start timer           

            end  

            elapsedTime = elapsedTime + toc;                               % Update elapsedTime with the time that elapsed since starting the timer
            fprintf('The percentage of received packets: %d \n',shimmer.getpercentageofpacketsreceived(timeStamp)); % Detect loss packets
            shimmer.stop;                                                  % Stop data streaming                                                    

        end 

    end

    shimmer.disconnect;
    
    
    
    clear shimmer;
end % plotandwriteecgexample