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"

GeneralBrand: Seeedstudio
Type: Modular Smartphone
Suitable for: Arduino
Output Current: 520mAh
Electronic ComponentsScreen Size: 1.54inch
Power BatteriesBatteries Included: Yes
Weight and SizeProduct 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

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.

MicrocontrollerMediatek MT2502
MCU Core32-bit ARM7EJ-STM RISC processor
Flash Memory16 MB
Power Supply3.3 ~ 4.2V(no SIM)/3.5 ~ 4.2V(with SIM)
Power Consumption20mW/30mW/52mW @ standby(no radio)/standby(GSM)/standby(BT)
Quad-band850/900/1800/1900 MHz
GPRSClass 12 modem
Clock Speed260 MHz
Connectors35 PIN Connector & 11 PIN Connector for Xadow Modules; JST 1.0 Connector for the battery
InterfacesLCD, Audio, I2C, SPI, UART, and GPIOs etc
Dimensions25.37mm × 20.30mm / 1” × 0.8”

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.

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.

GSM Breakout

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

  1. Up to 16 General Purpose Inputs/outputs (GPIOs)
  2. Interfaces like SPI, I2C, UART, etc.
  3. 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.

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, you should read it. Same problem happened to me, however I manage to remove it from the SIM card slot using a small piece of transparency.

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.

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.

Assemble the phone

Figure below 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...

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