The microwave uses a microcontroller (Arduino UNO) and a single board computer (Raspberry Pi) to support all the touch panel buttons. The Raspberry Pi is used for network communication using communication via MQTT, reading touch inputs and commanding the Arduino UNO. The Arduino UNO receives from the Raspberry Pi besides the command for resetting and opening the microwave, the pressed touch keys. The Arduino plays a different tone over the piezo depending on the key and can, if the correct key input (i.e. solving the puzzle), it can activate the relay, which triggers the solenoid and allows the microwave door to open. Furthermore the Arduino can show the time on the TFT display, which is configured by the RTC module.