Serial Communication App Designer

Hello! I m quite new in App Designer so I m gonna ask for your help. I need to open a serial communication with my Arduino. I have some erros though and I cannot understand why:

delete(instrfind)

arduinoo =arduino('COM6');

arduinoo=serial('COM6');

set(arduinoo, 'BaudRate', 115200);

arduinoo.Terminator = 'CR';

y=zeros(1);

s11=zeros(1);

s12=zeros(1);

s13=zeros(1);

s14=zeros(1);

i=1;

l2=0;

arduinoo.BytesAvailableFcnCount = 40;

arduinoo.BytesAvailableFcnMode = 'byte';

arduinoo.BytesAvailableFcn = @instrcallback;

fopen(arduinoo);

if isvalid(arduinoo)

tstart=now();

while 1<2

data=fscanf(arduinoo);

if real(str2double(data))< 5 & real(str2double(data)) >1.75

l2 = (now()-tstart)*24*60*60;

for j=1:1000

data=fscanf(arduinoo);

y(i+j)=real(str2ouble(data));

app.sa = 'DA';

end

break;

end

fclose(arduinoo);

delete(instrfind);

end

Here is my error:

Error using serial/fscanf (line 153)

Unsuccessful read: Instrument object OBJ is an invalid

object..

data=fscanf(arduinoo);

Error using matlab.ui.control.internal.controller.ComponentController/executeUserCallback (line 309)

Error while evaluating Button PrivateButtonPushedFcn.

Thank you in advance for any help!

Answer 1

[Harsha Priya Daggubati]

Hi,

I guess the issue is with arduinoo object you are creating, which I can infer is invalid. Can you try deleting and clearing the object from the workspace/memory and re-run your code.

You can refer the following documentation links for more help.

https://www.mathworks.com/help/instrument/delete.html

Hope this helps!

[Criss2112]

thank you so much for your time!

Still couldn't figure it out. I ve tried this way but I get the same error..

[Harsha Priya Daggubati]

Hi,

Is the issue resolved? I can only guess the issue is with 'arduinoo' object. Try doing as mentioned in the link:

https://www.mathworks.com/help/instrument/disconnecting-and-cleaning-up_f5-24524.html

One thing to add, it is suggested to use 'serialport' instead of 'serial'. Refer to the documentation for more details.

https://www.mathworks.com/help/instrument/serialport.html

[Criss2112]

Not yet, I read the serial simple in an Matlab script, registred the data into some files and then I used them in App Designer.

I had the same issues after doing this

I ll try also with serialport

Thank you!

[Harsha Priya Daggubati]

Also, make sure that the port number to which arduino is connected is same as that mentioned in your script, and baud rate is the same.

Have a look at this published File Exchange submission:

https://www.mathworks.com/matlabcentral/fileexchange/26371-simple-gui-for-serial-port-communication

[Criss2112]

Yes, it s the same. Com6 and 115200 the baudrate.It works perfectly fine in matlab script when running