Checking connection/ communication Can I ping or “hello world” an Arduino.
Background:  My son and I bought a 3-D printer kit.
(EZ-3D)

We are having some issues talking with it.  (Well we can't talk at all.)  So we thought to upload the firmware,

It’s an Arduino Mega 2560, and when we upload the Arduino times out… but it takes a minute or two.  Can I try some simpler program just to try and talk to the Arduino?  

I’m almost a “virgin” Arduino user so be gentle.
Adafruit has a good set of guides to getting started with arduino:
https://learn.adafruit.com/series/learn-arduino

The "Blink" program is the equivalent of "hello world".

When testing you probably should disconnect the Arduino from the 3D printer.