sudo mkdir /var/locksudo chmod 777 /var/lock
lsof | grep usbmodem
Yes, I've run the chmod command. I'm asked for password but the terminal doesn't return with anything. The mkdir command is returned with a "mkdir: /var/lock: File exists"
The grep usbmodem isn't returned with anything either even if the UNO is plugged in and blinking away.
The result is still the same: avrdude: stk500_recv(): programmer is not responding
How should the UNO look in the System Preferences - Network? Is it enough that it is just there and "not connected". I never got the "pop up" that is described in the manual...
ls -l /dev/tty.usb*
If you see /dev/tty.usbserial411 (or similar) in the Serial Port menu in the Arduino IDE, it sounds like the board is correctly being recognized by the computer. If you get a serial port in use error when you try to upload, it may be that there is actually another program on your computer trying to use the serial port. Things like USB internet dongles, PDA or cell phone sync applications, bluetooth terminals, etc. sometimes try to open and use any serial port that shows up on the computer. Do you have anything like that running?
Another test might be to run this terminal command with the Uno connected and disconnected:Code: [Select]ls -l /dev/tty.usb*This will give you an idea what serial port the Uno is being assigned.
I've even cleaned out traces of some old USB internet dongles I used some months ago and bluetooth is off.