Serial communication with Arduino

I am attempting some basic serial communication with an arduino with the following matlab code:

    %%ARDUINO INTERFACING
  % Connect to Arduino the specified port
  delete(instrfindall);
  Port = '/dev/tty.usbmodem1421';
  BaudRate = 9600;
  DataBits = 8;
  StopBits = 1;
  Parity = 'none';

% Create the serial connection and open communication with the Arduino.

ser = serial(Port);
set(ser, 'BaudRate', BaudRate);
set(ser, 'DataBits', DataBits);
set(ser, 'Parity', Parity);
set(ser, 'StopBits', 1);
set(ser, 'Terminator', 'LF');

fopen(ser);
disp('Serial port created')

% VERIFY SERIAL COMMUNICATION HAS BEEN SETUP
a = 'b';
while (~strcmpi(a,'a'))
       if (ser.BytesAvailable > 0)
           a = fread(ser,1,'uchar');
       end
end
if (strcmpi(a,'a'))
    disp('Serial read')
end
fprintf(ser,'%c','a');
mxbox = msgbox('Serial Communication Initialized'); uiwait(mxbox);

fclose(ser);
delete(ser);
clear ser;
delete(instrfindall);

The issue is there is no data being read so it gets stuck in the while loop while verifying. My arduino code successfully prints to the serial monitor so I think it's fine, it is:

void setup()
{
  Serial.begin(9600);
  Serial.println('a');
  char a = 'b';
  while (a != 'a')
  {
    a = Serial.read();
  }
}
void loop()
{
}

I have tried using numerous examples on this forum and around the internet but I simply cannot get any communication between the two. Any pointers would be greatly appreciated.

Thanks in advance.

Answer 1

[Pasc Peli]

What Oparating system are you on?

Answer 2

[William Gaillard]

I'm not sure why your code does not work as written but in Matlab when I changed:

while (~strcmpi(a,'a'))

to

    while (a~='a')

and

        if (strcmpi(a,'a'))

to

            if (a=='a')

it worked

I did not make any changes to Arduino