Can't connect MATLAB 2016 to Arduino using arduino() function ??

Hi,

I am working on a servo motor that's gonna receive an angle value from matlab. Previously we were using arduino ide but there were problems in creating an arduino serial communication. Then we began using serial communication with arduino built-in function in matlab 2016.

But problem did not go away. Even a few minutes ago, the servo was doing the job. Then when we ran the program again, this popped up, again,

" Failed to open serial port COM5 to communicate with board Mega2560. Make sure there is no other MATLAB arduino object for this board. For troubleshooting, see Arduino Hardware Troubleshooting."

This has been really frasustrating ! Please guyz, anyone have any idea what went wrong here or how to solve it ??

Thanks in advance.

a=arduino();
s=servo(a,'D9');
angle=30/180;
writePosition(s,angle);

Answer 1

[Walter Roberson]

You have an existing arduino object. The single easiest way to make certain it is gone is to restart MATLAB.

[Kazi]

Thanks Walter, that worked. All I had to do was write these two in the beginning of the code

clear a
clear s

That's it !

[Swapnil Desai]

I still can't get a connection, Is there any other solution ?

Answer 2

[HAMZA ABBASI]

write clear all in the first line of code

[Walter Roberson]

[Alex Barbu]

it doesnt work even I cleared all before writing the code. it gets the same error:

>> a=arduino('COM41','Uno');

Failed to open serial port COM41 to communicate with board Uno. Make sure there is no other MATLAB arduino object for

this board. For troubleshooting, see Arduino Hardware Troubleshooting.

[Walter Roberson]

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