Notice: this project's name has been changed from "Tyfone" to "TyTelli" to avoid confusion with Tyfone Inc.

Note that in the video TYOS 0.1.0 is used. Many, many new features have been added since then.

Hardware

The TyTelli is made up of a few basic components:

The Raspberry Pi handles all the processing, and connects everything together. The TFT talks to the Raspberry Pi over SPI, and the FONA talks to it over UART. Everything is powered with a 1200mah battery connected to the FONA. The FONA has a charging circuit perfect for use with the phone. Since the battery is only 3.7v, a boost converter is used to boost the voltage to 5v for the Raspberry Pi and TFT. A metal speaker and microphone is connected to the FONA for audio, along with an antenna. The FONA also has a real time clock built in, so the Raspberry Pi can keep time even when off wifi connection. The Raspberry Pi also has a USB Wifi Adapter connected to it giving it internet access. Right now all that it is used for is to upload camera photos to dropbox, but more features will be implemented in the future. The Raspberry Pi camera module is used for pictures and video. Below are some fritzing diagrams on how everything is connected.

The case is made up of two 3D printed parts with the Raspberry Pi, camera, and Fona screwed down inside. You can download the parts from thingiverse.

Software

The TyTelli runs software I wrote in python called TYOS. TYOS sends commands to the FONA to get the battery level, time, cellular connection, send/receive calls, and send sms messages.

Frequently Asked Questions

Can the TyTelli run Android?

No.

Why can't the TyTelli run Android?

The Raspberry Pi is not powerful enough.

If I use the Raspberry Pi 2 can it run Android?

With a lot of coding, maybe. Try it.

How much does the device cost?

Approximately $180 US Dollars.

Can other services besides T-Mobile be used?

Yes. Any network with 2G support and a full size SIM card.

TYOS isn't even a true OS. What's with that?

I wasn't in the mood for writing a completely new OS.

Why is the phone called TYtelli and the software TYos?

Creator = Tyler

Project = telephone

creator + project = TyTelli

Do you plan on upgrading the hardware/software?

There will probably be very few updates to the hardware, but I plan on expanding TYOS and it's capabilities.