#+SETUPFILE: ../../../template/level-2.org
#+TITLE: Arduino Phone
#+DATE: <2016-06-18 Sat 14:37>
#+AUTHOR: vaeringjar
#+EMAIL: vaeringjar@land
#+DESCRIPTION: Arduino Phone, another look at creating freer mobile hardware.
#+KEYWORDS: diy, phone, mobile


* Post

This post will likely seem like a rehash commercial praise of
Adafruit, though I only mean it to record the basic information for a
DIY mobile phone.

lady ada over at Adafruit has a guide for a DIY mobile phone
project. It looks about the same level of complexity as the PiPhone,
except explicitly with an Arduino instead of an ARM system-on-a-chip
controller. The parts for the entire guide total up to about
120$US. For a 3G radio, it costs around 30$US to 40$US more, depending
on the GSM module.

The basic kit involves the following parts:

- [Adafruit FONA 800 shield](https://www.adafruit.com/product/2468)
- [Adafruit TFT Shield w/Resistive touch](https://www.adafruit.com/product/1651)
- [Stacking headers](https://www.adafruit.com/product/85)
- [GSM SIM card](https://www.adafruit.com/product/2505)
- [1200mAh LiPoly Battery](https://www.adafruit.com/products/258)
- [Metro 328](https://www.adafruit.com/product/2466)
- [Wired electret microphone](https://www.adafruit.com/product/1064)
- [Small metal speaker](https://www.adafruit.com/product/1890)
- [A plug-in headset](https://www.adafruit.com/product/1966)


Essentially, to reiterate the design, the phone has a touch screen
interface to the main controller, in this case the Metro board. The
main controller then tells the GSM to make calls, and if I understand
correctly, to pass SMS messages, and to receive events such as
incoming calls, messages, and GPS information if the GSM chip has it
built-in. The actual call audio happens via the GSM chip, as far as I
can tell, though because these GSM chips also handle data, some of
them 3G, the main controller should also have the ability to VOIP.

At this point I have not actually started building anything yet, for
either the Arduin-o-Phone or the PiPhone. Still waiting for parts.

From a freedom perspective, the FONA 3G GSM module, for example, has
links to drivers and hardware specs. I have not seen the explicit
license for the GSM module. I delayed this project many times while
looking for the best case for libre hardware and software. I think
this finally gives a sufficient set, a little better than the PiPhone
which lacked some explanation of the GSM module itself. However, using
the resources from Arduino and Adafruit I think I could just combine
the better parts of each project.

Note particularly for that module: lady ada recommends beginners start
with the FONA 80x series, so for the moment I will probably mind that
advice.

At this point, I feel like the form factor of the assembled device
should come in quite a bit smaller than I originally envisioned.
Perhaps closer to a double-deck of cards instead of a 1980s phone.


* References

- [PiPhone](https://github.com/climberhunt/PiPhone)
- [Adafruit DIY Arduino Phone](https://learn.adafruit.com/arduin-o-phone-arduino-powered-diy-cellphone)
- [Adafruit-METRO-328-PCB Hardware source files](https://github.com/adafruit/Adafruit-METRO-328-PCB)
- [Adafruit FONA 3G Cellular Breakout](https://www.adafruit.com/products/3147)
- [Adafruit FONA 3G Cellular + GPS Breakout Downloads](https://learn.adafruit.com/adafruit-fona-3g-cellular-gps-breakout/downloads)
