Hardware Reference
In-Depth Information
Source Files
This section walks through which pieces of other people's open source material I used to
create my kit; it also explores my source files that are shared with you. The source files
include a circuit board created with the free version of Eagle and a 3D printing file for the
enclosure. You can find all these files at
www.bit.ly/blinkybuildings
or in
Appendix F
.
You
will need PCB layout software, such as the following options, to be able to replicate or
build off the derivative file:
Fritzing
2
from a schematic to making the PCB.
Eagle
3
3
.
Eagle offers a freeware version of its software that can be used for boards as simple as this ex-
ample but is closed source software. However, this software is quite accessible in the open
source hardware community, as the majority of users are familiar with Eagle.
KiCad
4
licensed under GNU GPL v2.
You will also need a 3D printing software if you choose to print out or modify the en-
closure, such as:
Blender (reviewed in
Chapter 8
)
OpenSCAD
SketchUp
When making an open source hardware project, the most important thing to consider is
whether people can rebuild the project from your source files. If so, you have a successful
open source hardware project! If not, you need to release more source code or include
more documentation.
As described in
Chapter 5
, I started my project by laying out the design process. My
design purpose was to elegantly blink 20 LEDs in the shape of the Empire State Building.
Given the scope and the specifications and requirements, I decided I would need a small,
low-cost chip and would have to charlieplex the LEDs to drive 20 of them.
I discovered a project close to my needs that charlieplexed 20 LEDs in a falling snow-
flake pattern. The file was licensed as CC-BY-SA. This designation means the schematic
can be copied or used for a derivative, but the new schematic must give attribution to the
original and must also share alike with the same terms. In addition, this schematic came
with recommended code, also licensed as CC-BY-SA. Before I did anything else, I con-
