Mega 2560 - can't find port/won't upload

Summary - I cannot select a port in the IDE for use with a Mega 2560 I just purchased and therefore I cannot upload to it.

Method - I have an Arduino Uno that I can upload and run programs on.
I unplug the USB cable from the Uno ... change my Board Setting to Mega 2560 ... plug the USB cable into the 2560. The "serial" selection under "Port" in the IDE is greyed out. Attempts to upload to the Mega 2560 fail.

More info - When I plug the Mega 2560 in, it's red power light comes on and a mysterious red light labeled 'L" blinks.

  • I am using a Macbook Pro running OSX 10.13.3
  • I am using Arduino IDE 1.8.5
  • The Mega has "Made in China" printed on it.
  • The first line in the error message is
    "ovrdude: ser_open(): can't open device "/dev/cu.usbmodem1411": No such file or directory"
    "usbmodem1411" is the port that shows up when I have the Arduino Uno plugged in. It is not an option with the Mega plugged in.

Could anyone point me to a fix?


You have installed the CORRECT driver for the MEGA?

A google search on my part turns up NO results for a MAC OS, "Mega driver".

In the description of the Mega at Mega 2560 R3 ATmega2560-16AU, Arduino Compatible –
I found the following -
" No drivers needed for Linux or Mac"

Maybe Mega 2560 with ATmega16U2 without firmware?


Is it a "sainsmart MEGA 2560" ?
How does one tell?
The only ID stuff printed on mine is "MEGA 2560" and "Made in China".


Since it's got a 16u2, it should not require any special drivers, so this is rather mysterious, and you've ruled out a bad cable (there's been a plague of bad cables with no data lines lately)...