This is the primary display and interpreter of all the collected data, featuring:

• Arduino Mega (Atmega 2560) 
• 240x128 pixel LCD
• Real-time clock with battery backup
• SD card module, for logging to csv
• NRF24L01 radio module
• Piezo buzzer and LED for alerts

A user can configure which doors are monitored/alarmed or not, there is also a event history that can be scrolled back through.

The RTC is used to record what time an event happens, there is a switch to toggle daylight savings time.

The SD card is only accessible by dismantling the case, so discreetly records all events as well as "power outages", data is stored in csv format.

A buzzer and led flash if an alarm is triggered.

Alarmed events are broadcast back though the radio network to the portable units.