Hardware Reference
In-Depth Information
of pinouts, the thickness of the PCB, the typical construction materials used, and the main
purpose of the board were all altered. This particular Arduino derivative's function was to
be embedded in wearables—a vastly different use than the Arduino team had previously
imagined for their microcontroller. The circular, thin (not to mention purple) LilyPad is to
be sewn into wearables with a needle and thread rather than solder and wire.
Of course, not all derivatives are this different. In fact, some are even more or less cop-
ies of the original.
Let's take the Arduino example one step further by considering a derivative of the de-
rivative. Adafruit's Flora is a derivative of the LilyPad (which is derivative of the Arduino
board). The Flora derivative has the same form factor as the LilyPad—it is circular in
shape and flat, and has copper petals around the exterior for ease of sewing—but has a
different function, with a different chip on board than found in the original LilyPad. The
Flora hardware introduced the ATmega32U4 chip into wearables with different function-
alities than the ATmega328 on the LilyPad (such as allowing for a USB hookup rather
than using an FTDI cable). Because these designs are all open source, the LilyPad deve-
loper was then able to roll the Flora's changes back into their design, and now LilyPad
also offers an Atmega32U4 product. Naturally, both products can compete in the market-
place, because they are open source hardware, nobody is suing over rights; rather, every-
one is focused on innovating. You can access the source files for LilyPad and Flora and
compare and contrast the design files for yourself:
Original LilyPad files linked from SparkFun's product page:
Flora derivative files listed in Github: github.com/adafruit/Ada-
fruit-Flora-Mainboard
New ATmega32U4 LilyPad design rolling in the Flora's ATmega32U4 im-
provements:
https://www.sparkfun.com/products/11190
This is how derivatives of open source work! People build off improvements and ideas
from others rather than reinventing the wheel each time. This process moves innovation
forward at a more efficient and more productive pace.
