It is cheap, simple, hackable, ...
Some of the nice features:

  • Instead of requiring a host software (like cec-client) it acts as a standard keyboard.
  • Provides Hyperion-compatible interface for Ambilight setups

It's not a dedicated development board, but it provides some nice development/debug features:

  • a LED
  • a DFU bootloader (can be enabled/disabled with a solder jumper)
  • ICSP header is broken out in case you break with the DFU feature or want to flash the AVR often...
  • Test pads for all interesting signals
    • CEC
    • CEC input
    • CEC output
    • HPD
    • I2C SCL/SDA
    • 5v
    • 3.3v
    • GND
  • ICSP header is broken out in case you break with the DFU feature or
    want to - SPI Port is broken out ( mostly for the WS2811 LED strip )
  • SPI Port is broken out ( mostly for the WS2811 LED strip )
  • Input 5v can be selected from USB (default) or HDMI. In case you want to develop an autonomous device.
  • TWI/I2C is wired to the HDMI bus. The goal is to be able to read the Physical address of the HTPC (currently hard-coded in firmware)
  • Hotplug Detection (HPD) is wired to the HDMI bus

Firmware status is a bit less advanced:

  • Working
    • CEC spy-mode
    • CEC read/write
    • RawHID USB debug
    • Keyboard emulation
    • Ambilight
  • ToDo
    • Currently hardcoded
      • Physical address
      • Device name
      • Keys mapping between CEC and Keyboard (ie: Currently only for my TV and Kodi)
    • Missing features
      • TV control (turn off, turn on, switch source)