Failed to open serial port COM3 to communicate with board Uno.

Encounter this error when i tried to connect my arduino board with my matlab :Failed to open serial port COM3 to communicate with board Uno. Make sure there is no other MATLAB arduino object for this board. For troubleshooting, see Arduino Hardware Troubleshooting.

Can anyone solve this?

[Madhu Govindarajan]

Have you confirmed that the board is indeed on that port if not have you tried mentioning the port explicitly?

Please provide us the exact code.

[ABHISHEK MAURYA]

before starting the serial communication you should properly check that serial port is free so write--->

clc;

    if ~isempty(instrfind)
     fclose(instrfind);
      delete(instrfind);
end

[sachintha dahanayaka]

thats wokrs me well thank you.

[hammad shamim]

thanks this works

[Rafael Medina]

I still get the error :/

[mengqi1995]

thanks this works

[Truong N. T. Nhu]

Thank you very much, this works for me also !

[kay Dee]

thanks this works very welll

they should upvote

[Anubha GUPTA]

works great! thanks!

Answer 1

[HAMZA ABBASI]

clear object name like (clear a) will not work.... write clear all statement in the first line of code

[Pathmashantha Senanayaka]

hellow everyone. I want to make serial communication with arduino mega using matlab guide. Can enyone Please show me example code.

Answer 2

[Aamil Patel]

Failed to open serial port COM3 to communicate with board Uno. Make sure there is no other MATLAB arduino object for this board. For troubleshooting, see Arduino Hardware Troubleshooting.

this is the error message i get

[PRAPTI GANGULY]

I got the same error message. Make sure there is no other object in the workspace. type 'clear' to clear the workspace and then try running the code.

Answer 3

[Yehia Khalifa]

Same issue here. Any solution?

[dany sandoval]

yes, i finded a solution: first: clear a ('a' it´s a object to clear) second: if ~isempty(instrfind) fclose(instrfind); delete(instrfind); end If the port is open, close the port and delete the state

[Cádmo Dias]

Thanks a lot!

Answer 4

[Amaresh A.R]

Hello everyone..

when i am trying to connect arduino which is connected on COM2 i get the below error..

"Failed to open serial port COM2 to communicate with board Uno. Make sure there is no other MATLAB arduino object for this board. For troubleshooting, see Arduino Hardware Troubleshooting."

how to overcome this problem... please help TYIA..

Answer 5

[shawn oneal]

Hi Everyone,

I recently started the Arduino engineering kit and ran into this problem. It ended up being the driver. I never opened the Arduino IDE while connected to the Arduino33 Iot. Once this is done, the driver download is suggested. After I downloaded that I got the simulink model to run with default host-board connection settings, except the serial comms baudrate which is 9600 and external mode communication interface set to Serial.

Hope this helps

Answer 6

[Emmanuel Arthur]

I am working on this Arduino kit R2 with arduino nano 33 IoT.

I am running the attached program on Simulink to the board but I get this error.

I followed the instruction given on the kit website (Engineering Kit! (arduino.cc) under designing a motor control system) using MATLAB version R2022b.

I have tried inputing the port manually under Simulink Configuration Parameters>Hardware Implementation>Host-board connection, yet I get the same problem.

Can I get some assistance?