Can you follow the troubleshooting steps and post the results of them?
1.- Verify that you can upload any Arduino example to your board.
2.- Verify that you have uploaded a StandardFirmata example to your board.
3.- Verify that the port name in the board component matches the port where you have your board connected.
4.- Verify that the port name has quotation marks.
5.- ModelPlug will not connect to the board if there is another application using the port. Verify you do not have other applications using
the port.
6.- If the simulation log does not show the board capabilities, try uploading the Firmata to your board again.
7.- When using multiple boards, your operating system may have changed the port names. Verify that the port names in the components correspond to each hardware board.
8.- Some boards like the Arduino Leonardo and compatible require the parameter UseDTR set to true. Change the parameter and test your board.
Most of the new Arduino boards require the parameter UseDTR set to true. Test both configurations (true and false).