I’d advise trying without the power supply plugged in until that you’ve established contact. Try a different USB cable as well, if you have one.
One other thing that you can try is to open up a terminal and try ls /dev/cu.usbmodem* , to see if the EBB is registering there.
If this is for one of our EggBot kits and you still can’t establish contact, please contact customer service directly– it might be worth the effort to send it back to us for diagnosis/repair.
