How to debug an Arduino sketch on a Mac?
So... I want to debug the WaterMote sketch, but I do not see an option in my Arduino IDE on Mac OS X. Is there a way to debug sketches using Macs? Searching online shows various and preferred options, but mostly on Windows (of which I don't have any at home).


It's definitely possible to debug a sketch with OS&nbsp;X. But it's definitely an advanced AVR topic, and if you're not experienced enough with embedded programming you should first try to avoid it, except if it is really necessary.

Debugging a sketch for an ATmega328 implies:


Running a flasher such as the AVR Dragon, the JTAG ICE 3, the STK500 or the AVR ONE; no cheap flasher implements the DebugWire protocol;
Setting up the debug fuse, which is an operation that can brick your MCU.


If you're using an ATmega32U4 (or alike), you won't be able to do it out of the box, as the 32U4 needs a JTAG connection for on-chip debugging.

Finally, once you got through that, you can bind a gdb to the AVR using AVaRICE. I'm not getting you through all that, because I really, really, strongly advise you not to do it until you're experienced enough to know what you're doing.


  Moteino with WaterMote sketch loaded
         connected via USB to the MacBook Pro
         Arduino IDE running, but I see strange "[][][]" square output in the Serial connection.
         I do not know what to make of this since that text is not in the WaterMote sketch.
  Is there a way to debug sketches loaded on Arduino clones using Arduino IDE on Macs?


It is very likely you did not setup the correct baudrate for the serial outputs. Arduino IDE defaults to 9600&nbsp;bits/s connections, whereas the WaterMote source code defines a 115,200&nbsp;bits/s connection. When you open the Serial Monitor change the setting at the right of the status bar.

And finally, be sure to uncomment the #define SERIAL_EN line to enable the serial communication and debug outputs.