Seeedstudio RePhone: Fun & Creative Modular DIY Smartphone

I'm not a Smartphone addict, I never interested in the features of Smartphone or which Smartphone is best for me. However, as a DIY enthusiast, the Seeedstudio RePhone catches my eye.

The open source hardware manufacturer (SeeedStudio) published the world's first open source, modular Smartphone (RePhone) in Kickstarter on September 23, 2015. RePhone is a GSM +BLE (Bluetooth Low Energy) phone, future version will support 4G LTE. I own a RePhone DIY Kit from Gearbest.

Step 1: RePhone Kit Create

The core of the RePhone is provided by Xadow GSM+BLE or by RePhone Core 4G Module, beyond these two core modules are 8 more chainable add-on modules to extend the features and functionalities. However, if you want to build your own smartphone in minutes, then the "Seeedstudio RePhone DIY Kit" is the way to go, it includes all the necessary basic components to build a GSM smartphone.

The list below shows the specification and the package contents of the "Seeedstudio RePhone DIY Kit"

Product Weight: 0.093 kg
Package Weight: 0.200 kg
Product Size(L x W x H): 7 x 7 x 3 cm / 2.75 x 2.75 x 1.18 inches
Package Size(L x W x H): 20 x 14 x 2 cm / 7.86 x 5.50 x 0.79 inches
Package Contents1 x Core Module, 1 x Audio Module, 1 x Touch Screen, 1 x GSM Breakout, 1 x 3.7V 520mAH Battery, 2 x Kraft Paper, 1 x English Manual 10 x Rivets 2032, 16 x Rivets 2040, 8 x Rivets 3035

Step 2: GSM+BLE Module

"Rephone Kit Create" come with a Xadow GSM+BLE module which supports quad-band 850/900/1800/1900MHz that covers any GSM network in the world. RePhone uses 2G Nano SIM card instead of Mini SIM or Micro SIM card. I'm facing a problem that I couldn’t find a nano SIM card for my smartphone, therefore I have to cut my Mini SIM card down to a nano SIM card.

Step 3: Touch Screen Module

RePhone uses a 1.54" capacitive touch screen, the TFT display contains 240x240 pixels that can be controlled individually to display up to 262K colors. The display is small (active area: 27.72mm × 27.72mm) but the touch sensitivity is good.

Step 4: Audio Module

The audio module combines speaker and microphone on one board, the speaker (0.7 watt, 8 ohm) volume is a bit low but the voice is clear. There is no jack socket allows you to insert the earphone unless you make it with your GSM Breakout.

Step 5: GSM Breakout

Connect the GSM Breakout to the GSM+BLE module via FPC (Flexible Printed Circuit) cable, you can easily access:

Up to 16 General Purpose Inputs/outputs (GPIOs)
Interfaces like SPI, I2C, UART, etc.
Pinout related to peripheral devices like speaker, audio headphone and microphones

I did not use the GSM Breakout at the moment, my GSM+BLE module is connecting to a touch screen where there is no spare connector which allows me to connect the GSM Breakout.

Note: Some of the pins are using 2.8V or 1.8V, higher voltage level might damages your device.

Step 6: How to Cut the SIM Card

Cutting the SIM card down from mini to nano isn't difficult. My mini SIM card has guide marks on the metal, these help me line up the Nano SIM on the mini SIM card and provide me with an area to cut out.

This article is very interesting. Same problem happened to me, however I manage to remove it from the SIM card slot using a small piece of transparency.

Step 7: How to Insert the FPC Cable

The modules can be connected together using FPC cable. Before inserting the FPC cable, make sure the slider (lever) is lifted up until it is completely open as shown in figure B, otherwise you will not able to insert the FPC cable into the connector.

Step 8: How to Use Push-In-Rivets

Simply push the head in and the grommet expands to hold it in place.

Please refer to the RePhone Kit Manual for additional guidance.

Step 9: Assemble the Phone (1)

Figure above shows how to connect the battery and antenna to the Xadow GSM+BLE module. Once the battery is connected to the GSM+BLE module, you should get about 4V (depend on your battery voltage) when measure on pin 3 & pin 6 of the GSM+BLE module without turn it ON. Therefore I'm going to connect the battery later.

Step 10: Assemble the Phone (2)

"RePhone DIY Kit" uses kraft paper for the phone case, all modules are sit on a kraft paper as shown in figure below.

Step 11: Assemble the Phone (3)

Done! If you want to make your own phone shell, here is the link where you can download the files which including Autocad DXF for CNC & laser cutter. More phone enclosure is available here and here.

Note: Make sure everything is working properly before fixing with rivets 3035, otherwise it is very difficult to pull out the rivets 3035 from your phone case.

Step 12: Turn ON/OFF the Phone

Press and hold the power key for 2 seconds to turn the phone ON, the green LED blinks once every second, the graphic interface appear on the screen within 3 seconds. RePhone will going into sleep mode after being idle for one minute. Press and hold the power key again for 2 seconds to turn the phone OFF.

Step 13: Battery Charging and Consumption

The Xadow GSM+BLE itself has a built-in charging circuit, which allows you to charging the battery using the USB port. The battery icon on the screen indicates the state of the battery. During charging, there is a "lightning bolt" appear on the battery icon, but it wouldn't shows the battery percentage on your screen.

The power consumption depends on how you use the phone, RePhone Kit Create comes with a 520mAH battery, however you cau use a bigger battery which can supply a voltage level of 3.5V-4.2V.

I tested my RePhone (GSM Module + Touch Screen Module + Audio Module) with a SIM card inserted. After putting it on for 20 hours without any call, the battery status shows excellent (the battery icon is completely filled in). Four hours later, checking the phone again, it's very surprising that the power has been cut off and the battery is completely discharged. These explains the battery can run for up to 20 hours or not more than 24 hours.

Step 14: Operating Modes

Seeedstudio RePhone (Xadow GSM+BLE) has two operating modes, i.e. the Mass Storage Mode or Flash/Debug mode.

Mass Storage Mode

Turn off the phone (Xadow GSM+BLE) and connect it (with battery connected) to PC via Micro USB cable, the LED indicator should change from Red to Green. It should appear as a "Removable Disk" and you can access the 5MB "Mass Storage" on PC. All the applications (including vxp files) and system settings are stored in this 5MB disk. You would have to put mp3 file in the mass storage as well for the use of ringtone.

Please read this article if Mass Storage Mode works in first time only.

Flash/Debug Mode

Turn on the phone (Xadow GSM+BLE) and connect it (with battery connected) to PC via Micro USB cable, the Green LED should start blinking. You can find two COM ports (MTK USB Debug Port & MTK USB Modem Port) on your "Device Manager" which allows you to update/flash the firmware. Additionally the MTK USB Debug Port is used for uploading code, and the MTK USB Modem Port is used for logs, like printing messages in the serial monitor.

Step 15: Software for "RePphone Kit Create"

"RePhone Kit Create" come with pre-installed software (Graphic Interface) which demonstrate the functions of the phone. If you know programming, the source code is available in GitHub where you can use it and program your phone (GSM+BLE module).

Step 16: Software Development Environment and Development Languages

Besides making and receiving calls, sending text messages, RePhone supports various development environment and development languages, you can either built applications with C/C++ based on Eclipse IDE, Arduino IDE, or with Lua and JavaScript.

Arduino IDE uses a simplified version of C++, making it easier to learn to program. Next article will show how to use the Arduino IDE for RePhone.

My website: http://ediy.com.my/blog/item/136-seeedstudio-rephone