smartled_hack

A reverse-engineering effort for Smart LED products. This project provides tools to control off-the-shelf smart LED products.

Hardware

• Raspberry Pi 3B+ (or any Linux/Bluetooth-capable devices)
• AKEPO Small Size 16W RGBW APP Twinkle Fiber Optic Lights (Amazon link)

Requirements

• Python libraries

  pip install asyncio bleak
  

Preliminary Finding

• It is a Bluetooth GATT device
• Destination Address: 21:0a:00:06:5a:b2
• Handle: 0x000d
• UUID: 0000ffb1-0000-1000-8000-00805f9b34fb
• Configs:
  • power: 00 or ff (off and on)
  • color: ff0000 (red, in hex)
  • twinkle: ff04 (on, speed 4)

Demo

This device is the work by Wan-Chien Lin, featuring in LEDucation 2023.

Presets

The presets are shared between PRESET mode and SOUND mode.

1. seven color fade
2. RGB fade
3. seven color breathe
4. RGB breathe
5. red & green fade
6. red & blue fade
7. green & blue fade
8. seven color jump
9. RGB jump
10. seven color flash
11. RGB flash
12. red flash
13. green flash
14. blue flash
15. yellow flash
16. purple flash
17. cyan flash
18. white flash
19. yellow & purple flash
20. purple & cyan flash

Packet Structure

total = 20 bytes

00: header 'a5'
01: power 'ff'/'00' (on/off)
02: operation mode: 0x00 for preset, 0x01 for manual, 0x04 for Sound mode
03: preset 0x00 - 0x13 (0 - 19, 20 presets). 0x00 or 0xff if manual?
04: speed 0x01 - 0x0a (1 - 10, 10 speeds) (seems not revelent in manual mode)
05: R 0x00 - 0xff (seems all 0x00 in preset mode)
06: G 0x00 - 0xff
07: B 0x00 - 0xff
08: padding 0x00
09: brightness 0x01 - 0x64 (1 - 100, 100 levels)
10: sound_onoff 0x00 or 0xff
11: sound_preset 0x00 - 0x13 (0 - 19, 20 modes)
12: Sound sensitivity 0x01 - 0x0a (1 - 10, 10 levels)
13: twinkle_toggle 0x00 or 0xff (off/on)
14: twinkle speed 0x01 - 0x04 (1 - 4, 4 speeds)
15: meteor on/off 0x00 or 0xff (on/off)
16: meteor preset 0x01 - 0x14 (1 - 20, 20 presets)
17: meteor speed 0x01 - 0x0a (1 - 10, 10 speeds)
18: padding 0x00
19: padding 0xaa

Command Template (WIP)

f'{header}{power}{mode}{preset}{speed}{color}{padding_1}{brightness}{sound_toggle}{sound_preset}{sound_sensitivity}{twinkle_toggle}{twinkle_speed}{meteor_toggle}{meteor_preset}{meteor_speed}{padding_2}'

where:
  header:             0xa5
  power:              0x00 or 0xff (off or on)
  mode:               0x00 for preset; 0x01 for manual; 0x04 for Sound mode
  preset:             0x00 - 0x13 (0 - 19, 20 presets)
  speed:              0x01 - 0x0a (1 - 10, 10 speeds)
  color:              0xRR 0xGG 0xBB (hex RGB color values, 3 bytes)
  padding_1:          0x00
  brightness:         0x01 - 0x64 (1 - 100, 100 levels)
  sound_onoff:       0x00 or 0xff (off or on)
  sound_preset:       0x00 - 0x13 (0 - 19, 20 modes)
  sound_sensitivity:  0x01 - 0x0a (1 - 10, 10 levels)
  twinkle_onoff:     0x00 or 0xff (off or on)
  twinkle_speed:      0x01 - 0x04 (1 - 4, 4 speeds)
  meteor_onoff:      0x00 or 0xff (off or on)
  meteor_preset:      0x01 - 0x14 (1 - 20, 20 presets)
  meteor_speed:       0x01 - 0x0a (1 - 10, 10 speeds)
  padding_2:          0x00 0xaa (2 bytes)

Formal Structure as a C++ class

g++ -std=c++20 -o btcmd_test btcmd_test.cpp
./btcmd_test

Output

BT packet size: 20

More details in btcmd.h.

class BTCmd {
 public:
  // Header
  HeaderPadding header : 8 = HeaderPadding::HEAD;

  // Power
  OnOff power : 8 = OnOff::ON; // off: 0x00; on: 0xff

  // Operation Mode
  OpMode opmode : 8 = OpMode::PRESET; // preset: 0x00; manual: 0x01; sound: 0x04

  // Preset
  Preset preset : 8 = Preset::SEVEN_COLOR_FADE; // 0x00 ~ 0x13 (0 - 19)
  int speed : 8 = 0x01; // 0x01 ~ 0x0a (1 - 10)

  // Manual Mode
  uint8_t red = 0xff;
  uint8_t green = 0xff;
  uint8_t blue = 0xff;
  // TODO(allenpthuang): check if it is in fact
  // `unit8 white = 0xff;`

  // Padding
  HeaderPadding padding_1 : 8 = HeaderPadding::PADDING_1;

  // Brightness
  int brightness : 8 = 0x01; // 0x01 ~ 0x64 (1 - 100)

  // Sound
  OnOff sound_onoff : 8 = OnOff::OFF; // off: 0x00; on: 0xff
  Preset sound_preset : 8 = Preset::SEVEN_COLOR_FADE; // 0x00 ~ 0x13 (0 - 19)
  int sound_sensitivity : 8 = 0x01; // 0x01 ~ 0x0a (1 - 10)

  // Twinkle
  OnOff twinkle_onoff : 8 = OnOff::OFF; // off: 0x00; on: 0xff
  int twinkle_speed : 8 = 0x01; // 0x01 ~ 0x04 (1 - 4)

  // Meteor
  OnOff meteor_onoff : 8 = OnOff::OFF; // off: 0x00; on: 0xff
  MeteorPreset meteor_preset : 8 = MeteorPreset::SEVEN_COLOR_FADE; // 0x01 ~ 0x14 (1 - 20)
  int meteor_speed : 8 = 0x01; // 0x01 ~ 0x04 (1 - 4)

  // Padding
  HeaderPadding padding_2 : 8 = HeaderPadding::PADDING_1;
  HeaderPadding padding_3 : 8 = HeaderPadding::PADDING_2;
};