HSC2011/Building your own EduBuzzer
In order to build an EduBuzzer, you'll need
equipment for etching a two sided PCB (as an alternative, you can order it just as well -- we didn't etch ours),
a rapid prototyper (3D printer, e.g. a makerbot),
and a copy of the EduBuzzer software and hardware description from the project download page.
The main board
For etching the main board, you'll find all required files in the hardware/gerber subdirectory of the repository, or you can directly use the Eagle files in hardware. For building an ergonomic buzzer, use the buzzer files.
As an alternative (to try it out with less effort), use the arduino_schield files -- with them, you need fewer components, and get an arduino shield you can plug onto an Arduino compatible device. If you are good at soldering and want to get going with what is present in a typical hackerspace (at least, in the metalab), you can produce the same circuit even on a prototyping shield.
Solder in all the components as described in the part list, starting with the big parts. We recommend to use sockets for both the ATMega328 and the RFM12B module, as they are prone to overheating from inexperienced soldering, and as there is no programming header exposed for the ATMega. (Updates can be flashed using a serial bootloader, but if you break something, things get tricky.) Other parts to take care of:
- R10 -- don't install it, it's for adjusting the compatibility behavior with respect to Arduino's DTR handling, and
- SW5 -- connect using about 5cm of cable, as the switch is installed in a dedicated slot in the case.
If you checked the functionality of the example, you can flash firmware/firmware.hex onto it. While you are at it, you can write the MAC addresses of the device and its configured base station directly to EEPROM in this step as well.
Print the enclosure as described in the enclosure directory in the repository.
You will get
- a top part,
- a bottom part,
- and an acryl part in that goes in between the others.
Put the battery under the bridge in the lower part of the enclosure, the contacts go to the narrow side. You may need to remove artefacts from the production from rapid prototyping. The switch is put in the socket at the other side of the lower part and can be screwed tight. The toggling part of the switch will slightly protude from the surface.
Align the holes in the board with the matching parts of the lower part and just screw it in somehow.