Just a bit more info about the PCB workshop this evening:
I will work through the design, schematic capture and layout of a simple
little microcontroller project I created especially for this workshop,
called the "Nanduino" (as in very small Arduino). The PCB measures 30mm x
35mm and incorporates an Atmel AT90USB162. It comes factory-programmed with
a USB bootloader. You can write code for it and upload it over USB using
freely-available tools, and since the micro's USB peripheral is a
general-purpose full-speed (12Mbit/s) USB device, you can program it to
enumerate as any of the common USB device types (e.g keyboard, mouse,
mass-storage, MIDI I/O, RS-232, audio I/O) in addition to custom USB device
types using Dean Camera's excellent LUFA library
(
http://www.fourwalledcubicle.com/LUFA.php). The total cost of materials (if
you're interested in making one) is about �5. I will bring a working board
to demo code upload and to show it working as a five-button USB keyboard
(woo!).
All PCB design work will be done using the freeware version of Eagle,
available for common platforms here:
http://www.cadsoft.de/download.htm.
The workshop focuses on design constraints for home-etched PCBs. We have the
equipment necessary to do this at the space on Barnsbury Terrace. I will not
cover commercial PCB fabrication in detail since I have only limited
experience there. Furthermore, whilst I can talk about the *process* of
home-etching, it's not something I can readily demo at the Hub, but there
are some pics of the progress of etching the Nanduino here:
http://www.makestuff.eu/nanduino.
* The first pic shows the board after having been UV-exposed and developed.
The combination of UV-exposure and the developer chemical has removed the
etch-resist from the lighter areas of the board, but note the overall
coppery colour remains, even in the lighter areas.
* The second picture shows the board after etching. The etchant has
dissolved the copper in the white areas, leaving metal behind for tracks and
pads.
* The third picture shows the board after drilling. This is the most boring
bit (hence my preference for surface-mount components!).
* The fourth picture shows the beginnings of my poor efforts at soldering.
Hope to see you there this evening!
- Chris
--------------------------------------------------
From: "Russ Garrett" <
ru...@garrett.co.uk>
Sent: Wednesday, December 02, 2009 10:34 AM
To: "London Hack Space" <
london-h...@googlegroups.com>
Subject: [london-hack-space] Re: Hackspace Hack Evening #20: Wednesday 2nd
December