Introduction: Logo Exchangeable Step Light (Door Sill)

Hall Sensor Triggered when you open your car door, you'll see what your own designed logo on step light bar.

Step 1: 3D Drawing and MockUP Sample

3D Drawing and Mockup!


  1. Hall Sensor
  2. Top Cover
  3. LCD Module 384 x 64
  4. Control pcb
  5. Bottom Cover
  6. Battery

Step 2: Control PCB

Hardware Design by

  1. Arduino based MCU
  2. BLE Module
  4. BackLight Driver

Step 3: Coding

Arduino IDE platfrom with Uno board with bootloader programmed,

  1. 9600bps Serial port for BLE module
  2. I2C EEPROM interface for logo image storage
  3. Lcd Module 384x64 driver interface connector
  4. Hall Sensor switch digital input
  5. Backlight LED Driver

Step 4: LCD Module Display Testing

Coding and Testing each interface and function

Disable BLE Function when debugging,

go to test display first, double check hardware design again.

Source code is attached.

Step 5: BLE Terminal Testing

BLE communication testing with EEPROM writing.

nRF UART app for Android. A simple app showing how to handle BLE with custom service in Android.

Step 6: BLE Module

Here you can fine reference Android source code!

BLE Module provider >>

Step 7: Android Studio Coding New Features

Download new Logos into phone storage.

Quick view logo and upload to control board after connect to the BLE Module.

Step 8: Whole Demo Testing

Smart Phone based logo upload to Step light.

With magnet attached on car door, when you open hall sensor triggered ....

You will see your on LOGO on step light bar.

to be continued OLED and LED Display.