Problem with de argument port?

Encounter this error when i tried to connect my arduino board with my matlab: Unable to create a communication link with the serial port. Please check the input argument PORT and verify that a device is connected.

Can anyone solve this?

[Juan Israel García Celedón]

My code:

a = arduino;
in_cero = 0;
in_hombro = 130;
in_brazo = 180;
in_mano1 = 90;

s_cuerpo = servo(a,'D2');
writePosition(s_cuerpo,(in_cero/180));

s_hombro = servo(a,'D3');
writePosition(s_hombro, in_hombro/180);

s_brazo = servo(a,'D4');
writePosition(s_brazo,in_brazo/180);

s_alabeo = servo(a,'D5');
writePosition(s_alabeo,in_mano1/180);

s_elevacion = servo(a,'D6');
writePosition(s_elevacion,in_cero/180);

s_cabeceo = servo(a,'D7');
writePosition(s_cabeceo, in_cero/180);

s_pinza = servo(a,'D8');
writePosition(s_pinza, in_cero/180);

[Walter Roberson]

Have you used

arduinosetup

[Juan Israel García Celedón]

Yes, I have

[Walter Roberson]

Which port did arduinosetup identify for use with your installed device? Have you tried hardcoding that port name in the arduino() call ?

Also, are you using Windows, or are you using Mac or Linux ?

[Juan Israel García Celedón]

Which port did arduinosetup identify for use with your installed device?

It is the COM4 port.

Have you tried hardcoding that port name in the arduino() call ?

Yes, I have, and Matlab showed me the same message. Just to be sure, it is like this: a = arduino('COM4','Mega2560');

Also, are you using Windows, or are you using Mac or Linux ?

I'm usign Windows

[Walter Roberson]

If arduinosetup was able to communicate with the port, but MATLAB is not able to communicate, then I do not know what is going on -- other than the possibility that the port is already in use ?

freeports = serialportlist("available")

freeports = "/dev/ttyS0"

[Juan Israel García Celedón]

It seems like it is available.

[Walter Roberson]

Sorry, the only other possibility is that coming to mind is the possibility of mismatch on baud rate, if the arduino has somehow been configured to an unusual rate... but then I would expect problems with the configuration process.

[Juan Israel García Celedón]

I configured the arduino with a different rate one month ago. I changed because when I wanted to use "arduinosetup" Matlab was giving me an error. Do you want me to show you the rate I changed it for?

[Walter Roberson]

Try using 'BaudRate' when you arduino()

[Juan Israel García Celedón]

How do I do that?

[Walter Roberson]

a = arduino('COM4', 'Mega2560', 'BaudRate', 38400);

or whatever baud rate you had set the arduino to. Try 9600, 38400, 19200

[Juan Israel García Celedón]

Well, that didn't work :/