This board is an extension board for an arcade cabinet build by the members of Nerdclub.dk, main reason is to be able to make propper shutdown of the arcade cabinet / rpi, and for making easy light control during startup / shutdown sequences.
Features of the board:
- Atmega328 for controlling the board, with the following "peripherals"
- 3 x 12V PWM channels for LED strips
- 1 x 5V PWM channel for the onboard FAN
- header for WS2812B strip (including level converter from 3v3 to 5v)
- Port for external relay board (for switching mains power)
- 1 button input routed to the atmeaga328
- RaspberryPI connected things
- 4 button inputs routed directly to the RPI GPIO header
- stereo channel I2S 3W class D amplifier (2 x MAX98357)
- I2C HAT eeprom for configuration
Atmega <-> RPI connections:
- Standard serial port
- SPI / ISP (rpi can reprogram the atmega directly via GPIO)
- I2C HAT eeprom (you could emulate RPI HAT eeprom in the atmega if wanted)
- Reset signal from RPI -> ATmega (disabled via jumper)