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PS4000aConfig;

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%% Parameter definitions
% Define any parameters that might be required throughout the script.
channelA = ps4000aEnuminfo.enPS4000AChannel.PS4000A_CHANNEL_A;
channelB = ps4000aEnuminfo.enPS4000AChannel.PS4000A_CHANNEL_B;

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>> channelA,channelB
channelA =
     0
channelB =
     1

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%% Device connection
if (exist('ps4000aDeviceObj','var') && ps4000aDeviceObj.isvalid && strcmp(ps4000aDeviceObj.status,'open'))
    openDevice = questionDialog(['Device object ps4000aDeviceObj has an open connection. ' ...
        'Do you wish to close the connection and continue?'], ...
        'Device Object Connection Open');
    if (openDevice == PicoConstants.TRUE) 
        % Close connection to device
        disconnect(ps4000aDeviceObj);
        delete(ps4000aDeviceObj);
    else
        % Exit script if User 
        return;
    end
end
ps4000aDeviceObj = icdevice('picotech_ps4000a_generic','ObjectVisibility','on'); 
% Connect device
connect(ps4000aDeviceObj);

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%% Display unit information
[infoStatus, unitInfo] = invoke(ps4000aDeviceObj, 'getUnitInfo');

disp('Device information:-')
disp(unitInfo);

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>> [infoStatus, unitInfo] = invoke(ps4000aDeviceObj, 'getUnitInfo')
infoStatus =
  11×1 uint32 column vector
   0
   0
   0
   0
   0
   0
   0
   0
   0
   0
   0

unitInfo =
  11×1 cell array
    {'Driver version: 2.1.82.3072'}
    {'USB version: 3.0'           }
    {'Hardware version: 1'        }
    {'Variant: 4824A'             }
    {'Batch & Serial: JW851/0014' }
    {'Cal. Date: 15Jul22'         }
    {'Kernel version: 1.0'        }
    {'Digital HW version: 1'      }
    {'Analogue HW version: 1'     }
    {'Firmware 1: 1.7.5.0'        }
    {'Firmware 2: 1.0.11.0'       }

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%% Channel setup
% All channels are enabled by default - switch off all except Channels A and B. 
% Channel A
channelSettings(1).enabled          = PicoConstants.TRUE; % 1
channelSettings(1).coupling         = ps4000aEnuminfo.enPS4000ACoupling.PS4000A_DC;% 1
channelSettings(1).range            = ps4000aEnuminfo.enPS4000ARange.PS4000A_2V;% 7
channelSettings(1).analogueOffset   = 0.0;

% Channel B
channelSettings(2).enabled          = PicoConstants.TRUE;
channelSettings(2).coupling         = ps4000aEnuminfo.enPS4000ACoupling.PS4000A_DC;
channelSettings(2).range            = ps4000aEnuminfo.enPS4000ARange.PS4000A_2V;
channelSettings(2).analogueOffset   = 0.0;

% Channel C
channelSettings(3).enabled          = PicoConstants.FALSE;
channelSettings(3).coupling         = ps4000aEnuminfo.enPS4000ACoupling.PS4000A_DC;
channelSettings(3).range            = ps4000aEnuminfo.enPS4000ARange.PS4000A_2V;
channelSettings(3).analogueOffset   = 0.0;

% Channel D
channelSettings(4).enabled          = PicoConstants.FALSE;
channelSettings(4).coupling         = ps4000aEnuminfo.enPS4000ACoupling.PS4000A_DC;
channelSettings(4).range            = ps4000aEnuminfo.enPS4000ARange.PS4000A_2V;
channelSettings(4).analogueOffset   = 0.0;

% Channel E
channelSettings(5).enabled          = PicoConstants.FALSE;
channelSettings(5).coupling         = ps4000aEnuminfo.enPS4000ACoupling.PS4000A_DC;
channelSettings(5).range            = ps4000aEnuminfo.enPS4000ARange.PS4000A_2V;
channelSettings(5).analogueOffset   = 0.0;

% Channel F
channelSettings(6).enabled          = PicoConstants.FALSE;
channelSettings(6).coupling         = ps4000aEnuminfo.enPS4000ACoupling.PS4000A_DC;
channelSettings(6).range            = ps4000aEnuminfo.enPS4000ARange.PS4000A_2V;
channelSettings(6).analogueOffset   = 0.0;

% Channel G
channelSettings(7).enabled          = PicoConstants.FALSE;
channelSettings(7).coupling         = ps4000aEnuminfo.enPS4000ACoupling.PS4000A_DC;
channelSettings(7).range            = ps4000aEnuminfo.enPS4000ARange.PS4000A_2V;
channelSettings(7).analogueOffset   = 0.0;

% Channel H
channelSettings(8).enabled          = PicoConstants.FALSE;
channelSettings(8).coupling         = ps4000aEnuminfo.enPS4000ACoupling.PS4000A_DC;
channelSettings(8).range            = ps4000aEnuminfo.enPS4000ARange.PS4000A_2V;
channelSettings(8).analogueOffset   = 0.0;

% Obtain the number of analog channels on the device from the driver
numChannels = get(ps4000aDeviceObj, 'channelCount');

for ch = 1:numChannels
    status.setChannelStatus(ch) = invoke(ps4000aDeviceObj, 'ps4000aSetChannel', ...
        (ch - 1), channelSettings(ch).enabled, ...
        channelSettings(ch).coupling, channelSettings(ch).range, ...
        channelSettings(ch).analogueOffset);
end

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% Obtain the range and units for each enabled channel. For the PicoScope 4824, this will be in millivolts.
[chARange, chAUnits] = invoke(ps4000aDeviceObj, 'getChannelInputRangeAndUnits', ps4000aEnuminfo.enPS4000AChannel.PS4000A_CHANNEL_A);
[chBRange, chBUnits] = invoke(ps4000aDeviceObj, 'getChannelInputRangeAndUnits', ps4000aEnuminfo.enPS4000AChannel.PS4000A_CHANNEL_B);

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>> ps4000aEnuminfo.enPS4000AChannel.PS4000A_CHANNEL_A
ans =
     0

>> ps4000aEnuminfo.enPS4000AChannel.PS4000A_CHANNEL_B
ans =
     1

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>> chARange, chAUnits
chARange =
        2000
chAUnits =
    'mV'

>> chBRange, chBUnits
chBRange =
        2000
chBUnits =
    'mV'

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% Obtain the maximum Analog Digital Converter Count value from the driver
% - this is used for scaling values returned from the driver when data is
% collected.
maxADCCount = double(get(ps4000aDeviceObj, 'maxADCValue'));

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>> maxADCCount
maxADCCount =
       32767

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%% Set data buffers
% Data buffers for Channel A and B - buffers should be set with the
% (lib)ps400a shared library, and these *MUST* be passed with application
% buffers to the wrapper shared library. This will ensure that data is
% correctly copied from the shared library buffers for later processing.

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overviewBufferSize  = 250000; % Size of the buffer(s) to collect data from the driver's buffer(s).
segmentIndex        = 0;   
ratioMode           = ps4000aEnuminfo.enPS4000ARatioMode.PS4000A_RATIO_MODE_NONE; % rationMode = 0;

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% Buffers to be passed to the driver
pDriverBufferChA = libpointer('int16Ptr',zeros(overviewBufferSize,1,'int16'));
pDriverBufferChB = libpointer('int16Ptr',zeros(overviewBufferSize,1,'int16'));

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>> pDriverBufferChA
pDriverBufferChA =
libpointer

>> pDriverBufferChB
pDriverBufferChB =
libpointer

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>> whos pDriverBufferChA pDriverBufferChB
  Name                  Size            Bytes  Class          Attributes
  pDriverBufferChA      1x1                    lib.pointer              
  pDriverBufferChB      1x1                    lib.pointer     

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status.setDataBufferChA = invoke(ps4000aDeviceObj, 'ps4000aSetDataBuffer', ...
    channelA, pDriverBufferChA, overviewBufferSize, segmentIndex, ratioMode);% status.setDataBufferChA = 0;
status.setDataBufferChB = invoke(ps4000aDeviceObj, 'ps4000aSetDataBuffer', ...
   channelB, pDriverBufferChB, overviewBufferSize, segmentIndex, ratioMode);% status.setDataBufferChB = 0;

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% Application Buffers - these are for temporarily copying data from the driver.
pAppBufferChA = libpointer('int16Ptr',zeros(overviewBufferSize,1)); % overviewBufferSize = 250000;
pAppBufferChB = libpointer('int16Ptr',zeros(overviewBufferSize,1));

% Streaming properties and functions are located in the Instrument Driver's Streaming group.
streamingGroupObj = get(ps4000aDeviceObj, 'Streaming');
streamingGroupObj = streamingGroupObj(1);

% Register application buffer and driver buffers (with the wrapper driver).
status.setAppAndDriverBuffersA = invoke(streamingGroupObj, 'setAppAndDriverBuffers', channelA, ...
    pAppBufferChA, pDriverBufferChA, overviewBufferSize); % status.setAppAndDriverBuffersA = 0;
status.setAppAndDriverBuffersB = invoke(streamingGroupObj, 'setAppAndDriverBuffers', channelB, ...
   pAppBufferChB, pDriverBufferChB, overviewBufferSize);  % status.setAppAndDriverBuffersB = 0;

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% Use default value for streaming interval which is 1e-6 for 1 MS/s.
% Collect data for 1 second with auto stop. The maximum array size will
% depend on the PC's resources. For further information, type |memory| in
% the MATLAB Command Window and press Enter.
%
% To change the sample interval set the |streamingInterval| property of the
% |Streaming| group object. The call to |ps4000aRunStreaming()| will output the actual
% sampling interval used by the driver.

% For 200 kS/s, specify 5 us
%set(streamingGroupObj, 'streamingInterval', 5e-6);

% For 10 MS/s, specify 100 ns (0.1 us)
%set(streamingGroupObj, 'streamingInterval', 100e-9);

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% Set the number of pre- and post-trigger samples
% If no trigger is set 'numPreTriggerSamples' is ignored
set(ps4000aDeviceObj, 'numPreTriggerSamples', 0);
set(ps4000aDeviceObj, 'numPostTriggerSamples', 2000000);

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% The autoStop parameter can be set to false (0).
%set(streamingGroupObj, 'autoStop', PicoConstants.FALSE);

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% Set other streaming parameters
downSampleRatio     = 1;
downSampleRatioMode = ps4000aEnuminfo.enPS4000ARatioMode.PS4000A_RATIO_MODE_NONE; % downSampleRatioMode = 0;

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% Defined buffers to store data collected from the channels.
% If capturing data without using the autoStop flag, or if using a trigger 
% with the autoStop flag, allocate sufficient space (1.5 times the size is 
% shown below) to allow for pre-trigger data. Pre-allocating the array is 
% more efficient than using vertcat to combine data.
maxSamples = get(ps4000aDeviceObj, 'numPreTriggerSamples') + ...
    get(ps4000aDeviceObj, 'numPostTriggerSamples');

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>> maxSamples
maxSamples =
     2000000

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% Take into account the downsampling ratio mode - required if collecting
% data without a trigger and using the autoStop flag. 
% finalBufferLength = round(1.5 * maxSamples / downSampleRatio);

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pBufferChAFinal = libpointer('int16Ptr', zeros(maxSamples, 1, 'int16'));
pBufferChBFinal = libpointer('int16Ptr', zeros(maxSamples, 1, 'int16'));

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>> pBufferChAFinal
pBufferChAFinal =
libpointer

>> pBufferChBFinal
pBufferChBFinal =
libpointer

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% Prompt User to indicate if they wish to plot live streaming data.
plotLiveData = questionDialog('Plot live streaming data?', 'Streaming Data Plot');
if (plotLiveData == PicoConstants.TRUE)
    disp('Live streaming data collection with second plot on completion.');
else
    disp('Streaming data plot on completion.');
end

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% Start streaming data collection.
[status.runStreaming, actualSampleInterval, sampleIntervalTimeUnitsStr] = ...
    invoke(streamingGroupObj, 'ps4000aRunStreaming', downSampleRatio, ...
    downSampleRatioMode, overviewBufferSize);

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>> status.runStreaming, actualSampleInterval, sampleIntervalTimeUnitsStr
ans =
     0

actualSampleInterval =
  uint32
   1

sampleIntervalTimeUnitsStr =
    'us'

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% Variables to be used when collecting the data
isAutoStopSet       = PicoConstants.FALSE; % 0
newSamples          = 0; % Number of new samples returned from the driver.
previousTotal       = 0; % The previous total number of samples.
totalSamples        = 0; % Total number of samples captured by the device.
startIndex          = 0; % Start index of data in the buffer returned (zero-based).
hasTriggered        = 0; % To indicate if trigger event has occurred.
triggeredAtIndex    = 0; % The index in the overall buffer where the trigger occurred (zero-based).

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% Display a 'Stop' button.
[~, stopFig.h] = stopButton(); % `stopButton` from PicoScope Support Toolbox   

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function [f, h] = stopButton()
% STOPBUTTON Displays a stop button.
%   [F, H] = STOPBUTTON() displays a Stop button to check abort data collection - 
%   based on MathWorks solution 1-15JIQ (http://uk.mathworks.com/matlabcentral/answers/100558-how-do-i-set-up-a-uicontrol-callback-to-interrupt-a-routine) and MATLAB Central Forum.
%   F is the handle to the button's figure, H is the uicontrol object.
%
%   Copyright: © 2014 - 2015 Pico Technology Ltd. All rights reserved.
%
%   See also FIGURE, UICONTROL.
    f = figure('Name', 'Stop Button', 'menubar', 'none',...
              'units', 'pix',...
              'pos', [400 400 100 50]);
    h = uicontrol('string', 'STOP', ...
                'callback', 'setappdata(gcf, ''run'', 0)', 'units', 'pixels',...
                'position',[10 10 100 30]);
end

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flag = 1; % Use flag variable to indicate if the stop button has been clicked (0).
setappdata(gcf, 'run', flag);

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% Plot Properties - these are for displaying data as it is collected. In
% this example, data is displayed in millivolts. 
if (plotLiveData == PicoConstants.TRUE)
    % Plot on a single figure 
    figure1 = figure('Name','PicoScope 4000 Series (A API) Example - Streaming Mode Capture', ...
         'NumberTitle','off');
     axes1 = axes('Parent', figure1);

    % Estimate x-axis limit to try and avoid using too much CPU resources
    % when drawing - use max voltage range selected if plotting multiple
    % channels on the same graph.
    xlim(axes1, [0 (actualSampleInterval * maxSamples)]);

    yRange = max(chARange, chBRange);
    ylim(axes1,[(-1 * yRange) yRange]);

    hold(axes1,'on');
    grid(axes1, 'on');

    title(axes1, 'Live Streaming Data Capture');
    xLabelStr = strcat('Time (', sampleIntervalTimeUnitsStr, ')');
    xlabel(axes1, xLabelStr);
    ylabel(axes1, getVerticalAxisLabel(chAUnits));
end

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...
status.getStreamingLatestValues = invoke(streamingGroupObj, 'getStreamingLatestValues');
...

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while (isAutoStopSet == PicoConstants.FALSE && status.getStreamingLatestValues == PicoStatus.PICO_OK)
    ready = PicoConstants.FALSE; % PicoConstants.FALSE = 0;
   
    while (ready == PicoConstants.FALSE)
       % Collect data
       status.getStreamingLatestValues = invoke(streamingGroupObj, 'getStreamingLatestValues');

       % Chek whether ready
       ready = invoke(streamingGroupObj, 'isReady');

       % Give option to abort from here
       flag = getappdata(gcf, 'run');
       drawnow;
       
       if (flag == 0)
            disp('STOP button clicked - aborting data collection.')
            break
       end
       if (plotLiveData == PicoConstants.TRUE)
            drawnow;
       end
    end
    ...
    % Check if auto stop has occurred.
    isAutoStopSet = invoke(streamingGroupObj, 'autoStopped');
    if (isAutoStopSet == PicoConstants.TRUE)
       disp('AutoStop: TRUE - exiting loop.');
       break
    end
   
    % Check if 'STOP' button pressed.
    flag = getappdata(gcf, 'run');
    drawnow;
    if (flag == 0)
        disp('STOP button clicked - aborting data collection.')
        break
    end
end

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while (isAutoStopSet == PicoConstants.FALSE && status.getStreamingLatestValues == PicoStatus.PICO_OK)
    ...
    while (ready == PicoConstants.FALSE)
      ...
    end
    % Check for new data values
    [newSamples, startIndex] = invoke(streamingGroupObj, 'availableData');

    if (newSamples > 0)
        % Check if the scope has triggered
        [triggered, triggeredAt] = invoke(streamingGroupObj, 'isTriggerReady');

        if (triggered == PicoConstants.TRUE)
            % Adjust trigger position as MATLAB does not use zero-based indexing.
            bufferTriggerPosition = triggeredAt + 1;
            fprintf('Triggered - index in buffer: %d\n', bufferTriggerPosition);
            hasTriggered = triggered;

            % Set the total number of samples at which the device triggered.
            triggeredAtIndex = totalSamples + bufferTriggerPosition;
        end

        previousTotal = totalSamples;
        totalSamples  = totalSamples + newSamples;

        % Printing to console can slow down acquisition - use for demonstration.
        fprintf('Collected %d samples, startIndex: %d total: %d.\n', newSamples, startIndex, totalSamples);
        
        % Position indices of data in the buffer(s).
        firstValuePosn = startIndex + 1;
        lastValuePosn = startIndex + newSamples;
        
        % Convert data values from the application buffer(s) - in this example
        bufferChAmV = adc2mv(pAppBufferChA.Value(firstValuePosn:lastValuePosn),chARange,maxADCCount);
        bufferChBmV = adc2mv(pAppBufferChB.Value(firstValuePosn:lastValuePosn),chBRange,maxADCCount);

        % Process collected data further if required - this example plots
        % the data if the User has selected 'Yes' at the prompt.
        
        % Copy data into the final buffer(s).
        pBufferChAFinal.Value(previousTotal + 1:totalSamples) = bufferChAmV;
        pBufferChBFinal.Value(previousTotal + 1:totalSamples) = bufferChBmV;
        
        if (plotLiveData == PicoConstants.TRUE)
            % Time axis
            % Multiply by ratio mode as samples get reduced.
            time = (double(actualSampleInterval) * double(downSampleRatio)) * (previousTotal:(totalSamples - 1));
            plot(time, bufferChAmV, time, bufferChBmV);
        end

        % Clear variables.
        clear bufferChAmV bufferChBmV firstValuePosn lastValuePosn ...
            startIndex triggered triggerAt;
    end
	...
end

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...
while (isAutoStopSet == PicoConstants.FALSE && status.getStreamingLatestValues == PicoStatus.PICO_OK)
    ...
    if (newSamples > 0)
        % Check if the scope has triggered
        [triggered, triggeredAt] = invoke(streamingGroupObj, 'isTriggerReady');

        if (triggered == PicoConstants.TRUE)
            % Adjust trigger position as MATLAB does not use zero-based indexing.
            bufferTriggerPosition = triggeredAt + 1;
            fprintf('Triggered - index in buffer: %d\n', bufferTriggerPosition);
            hasTriggered = triggered;

            % Set the total number of samples at which the device triggered.
            triggeredAtIndex = totalSamples + bufferTriggerPosition;
        end
    ...
    end
 end
 ...
if (hasTriggered == PicoConstants.TRUE)
    fprintf('Triggered at overall index: %d\n', triggeredAtIndex);
end
...

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previousTotal = totalSamples;
totalSamples  = totalSamples + newSamples;

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% Position indices of data in the buffer(s).
firstValuePosn = startIndex + 1;
lastValuePosn = startIndex + newSamples;

% Convert data values from the application buffer(s) - in this example
bufferChAmV = adc2mv(pAppBufferChA.Value(firstValuePosn:lastValuePosn),chARange,maxADCCount);
bufferChBmV = adc2mv(pAppBufferChB.Value(firstValuePosn:lastValuePosn),chBRange,maxADCCount);

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% Process collected data further if required - this example plots
% the data if the User has selected 'Yes' at the prompt.

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% Copy data into the final buffer(s).
pBufferChAFinal.Value(previousTotal + 1:totalSamples) = bufferChAmV;
pBufferChBFinal.Value(previousTotal + 1:totalSamples) = bufferChBmV;

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if (plotLiveData == PicoConstants.TRUE)
    % Time axis
    % Multiply by ratio mode as samples get reduced.
    time = (double(actualSampleInterval) * double(downSampleRatio)) * (previousTotal:(totalSamples - 1));
    plot(time, bufferChAmV, time, bufferChBmV);
end

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clear bufferChAmV bufferChBmV firstValuePosn lastValuePosn ...
    startIndex triggered triggerAt;

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% Close the STOP button window
if (exist('stopFig', 'var'))
    close('Stop Button');
    clear stopFig;
end

if (plotLiveData == PicoConstants.TRUE)
    drawnow
end

if (hasTriggered == PicoConstants.TRUE)
    fprintf('Triggered at overall index: %d\n', triggeredAtIndex);
end

if (plotLiveData == PicoConstants.TRUE)
    % Take hold off the current figure
    hold off;
    movegui(figure1, 'west');
end
fprintf('\n');

%% Stop the device
% This function should be called regardless of whether the |autoStop|
% property is enabled or not.
status.stop = invoke(ps4000aDeviceObj, 'ps4000aStop');

%% Find the number of samples
% This is the number of samples held in the |(lib)ps4000a| shared library itself. The actual
% number of samples collected when using a trigger is likely to be greater.
[status.noOfStreamingValues, numStreamingValues] = invoke(streamingGroupObj, 'ps4000aNoOfStreamingValues');
fprintf('Number of samples available from the driver: %u.\n\n', numStreamingValues);

%% Process data
% Process all data if required

% Reduce size of arrays if required.
if (totalSamples < maxSamples)
    pBufferChAFinal.Value(totalSamples + 1:end) = [];
    pBufferChBFinal.Value(totalSamples + 1:end) = [];
end


% Retrieve data for the Channels.
channelAFinal = pBufferChAFinal.Value();
channelBFinal = pBufferChBFinal.Value();

% Plot the total data collected on another figure.
finalFigure = figure('Name','PicoScope 4000 Series (A API) Example - Streaming Mode Capture', ...
    'NumberTitle','off');
finalFigureAxes = axes('Parent', finalFigure);
hold(finalFigureAxes, 'on');

title('Streaming Data Capture (Final)');
xLabelStr = strcat('Time (', sampleIntervalTimeUnitsStr, ')');
xlabel(finalFigureAxes, xLabelStr);
ylabel(finalFigureAxes, 'Voltage (mV)');

% Find the maximum voltage range.
maxYRange = max(chARange, chBRange);
ylim(finalFigureAxes,[(-1 * maxYRange) maxYRange]);

% Calculated values for time axis, then plot.
timeAxis = (double(actualSampleInterval) * double(downSampleRatio)) * (0:length(channelAFinal) - 1);
plot(finalFigureAxes, timeAxis, channelAFinal, timeAxis, channelBFinal);

grid(finalFigureAxes, 'on');
legend(finalFigureAxes, 'Channel A', 'Channel B');
hold(finalFigureAxes, 'off');

movegui(finalFigureAxes, 'east');
%% Disconnect device
% Disconnect device object from hardware.
disconnect(ps4000aDeviceObj);
delete(ps4000aDeviceObj);

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overviewBufferSize  = 250000; % Size of the buffer(s) to collect data from the driver's buffer(s).
segmentIndex        = 0;   
ratioMode           = ps4000aEnuminfo.enPS4000ARatioMode.PS4000A_RATIO_MODE_NONE;

% Buffers to be passed to the driver
pDriverBufferChA = libpointer('int16Ptr',zeros(overviewBufferSize,1,'int16'));

status.setDataBufferChA = invoke(ps4000aDeviceObj, 'ps4000aSetDataBuffer', ...
    channelA, pDriverBufferChA, overviewBufferSize, segmentIndex, ratioMode);

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% Application Buffers - these are for temporarily copying data from the driver.
pAppBufferChA = libpointer('int16Ptr',zeros(overviewBufferSize,1));

% Streaming properties and functions are located in the Instrument Driver's Streaming group.
streamingGroupObj = get(ps4000aDeviceObj, 'Streaming');
streamingGroupObj = streamingGroupObj(1);

% Register application buffer and driver buffers (with the wrapper driver).
status.setAppAndDriverBuffersA = invoke(streamingGroupObj, 'setAppAndDriverBuffers', channelA, ...
    pAppBufferChA, pDriverBufferChA, overviewBufferSize);

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maxSamples = get(ps4000aDeviceObj, 'numPreTriggerSamples') + ...
    get(ps4000aDeviceObj, 'numPostTriggerSamples');

pBufferChAFinal = libpointer('int16Ptr',zeros(maxSamples,1,'int16'));

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>> maxSamples
maxSamples =
     2000000

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maxSamples = get(ps4000aDeviceObj, 'numPreTriggerSamples') + ...
    get(ps4000aDeviceObj, 'numPostTriggerSamples');

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% Set the number of pre- and post-trigger samples
% If no trigger is set 'numPreTriggerSamples' is ignored
set(ps4000aDeviceObj, 'numPreTriggerSamples', 0);
set(ps4000aDeviceObj, 'numPostTriggerSamples', 1000000);
...
maxSamples = get(ps4000aDeviceObj, 'numPreTriggerSamples') + ...
    get(ps4000aDeviceObj, 'numPostTriggerSamples');

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% The autoStop parameter can be set to false (0).
set(streamingGroupObj, 'autoStop', PicoConstants.FALSE);