The DFRobot Beetle is one the latest innovations in minimalistic Arduino technology. About the size of a quarter, and the capabilities of an Arduino Leonardo, this tiny guy can minimize your projects with ease without having to sacrifice functionality.
After working with the Beetle, I am going to show you some tips and necessary tricks I learned to get this little device working properly over a Bluetooth HC-06 module.
Step 1: About the Beetle
The Beetle is sold by DFRobot for about $8 (http://www.dfrobot.com/index.php?route=product/product&product_id=1075) and gets cheaper the more you purchase. Programmable through micro USB, the Beetle is very easy to use and functions just like an Arduino Leonardo.
The website has all the details about the product itself, so I will focus solely on how to get this thing wireless through Bluetooth.
Step 2: Power
The Beetle specs says it requires 5 volts to operate, but it can also function at 3.7V. This is handy, because most LiPo batteries operate at 3.7V and are sold at most hobby stores. I used Tenergy because I have a bunch for quadcopters, but really any 3.7V source should do; however, do not exceed 5 volts to avoid risk of frying the surface components.
Unfortunately, the Beetle doesn’t have a way to plug in a battery directly unless you decide to solder on a female connector or supply power through the micro USB port. But, there are power terminals which we’ll see in the next step.
Step 3: Where to Supply Power
The Beetle has two terminals where you can supply power. On either end there are two plus and minus (hot and ground) terminals that can be used to supply power. The pictures above show the Beetle turning on with the battery.
Note: The LED will blink blue when the device is on until you upload a new code to the Beetle, then it will not turn on anymore unless you write digital 13 high.
Important Note: Don’t mix up your hot and ground when wiring, your Beetle will get very hot and possibly melt components!
Step 4: Bluetooth HC-06
One of my favorite and easy to use Bluetooth modules is the HC-06. This module uses TTL serial communication over a virtual COM port to stream data to the computer from the Beetle.
The great thing about this module is that it can also be powered with the same 3.7V LiPo battery by hooking it up in parrelel with the Beetle circuit.
Read more: Beetle: Minimize Your Arduino Projects