Matlab-Arduino live plotting - matlab

Question

I am trying to send data from my arduino to matlab and use the GUI. I want to read continously the data even when no button is pressed. In order to so, i have to use the fscanf function but i don't know where to put it. There is definitely a while loop that waits the events(such as a pushed button) in which this function should be placed. I am just a beginner so this might be a silly question for you.
Thank you in advance!
function varargout = UltraPlot(varargin)
global a;
global k;
gui_Singleton = 1;
gui_State = struct('gui_Name', mfilename, ...
'gui_Singleton', gui_Singleton, ...
'gui_OpeningFcn', #UltraPlot_OpeningFcn, ...
'gui_OutputFcn', #UltraPlot_OutputFcn, ...
'gui_LayoutFcn', [] , ...
'gui_Callback', []);
if nargin && ischar(varargin{1})
gui_State.gui_Callback = str2func(varargin{1});
end
if nargout
[varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});
else
gui_mainfcn(gui_State, varargin{:});
end
disp('Ultraplot');
function UltraPlot_OpeningFcn(hObject, eventdata, handles, varargin)
global a;
global k;
a = serial('COM3');
fopen(a);
handles.output = hObject;
guidata(hObject, handles);
disp('Opening');
function varargout = UltraPlot_OutputFcn(hObject, eventdata, handles)
varargout{1} = handles.output;
global a;
global k;
disp('varargout');
function Start_Callback(hObject, eventdata, handles)
global a;
global k;
fprintf(a,'%d',1);
disp('Button pressed');

Answer 1

You have to set Matlab to wait for any data from Arduino in a while loop, check this sample code :
clear;clc;
S=serial('com18'); % Create an S Object
data=0;
set(S,'inputbuffersize',4096,'timeout',20); % Set serial communication parameter
fopen(S); % Open serial communcation
while (1)
if s.bytesavailable>0 % If data from Arduino is available
data=fscanf(S);
data = str2num(data);
% Do whatever you want with data here...
end
data=0;
end