DoorBell-MQTT-Gateway

Based on

• Arduino Uno
• Ethernet interface using MQTT

Watchout for GPIO changes as triggers for

• door bell input
• mailbox observer (post entry)
• mailbox observer (takeout posts)
• light requests (button)

Serve outputs (using relays to trigger) for

• turn light on at mailbox
• turn bell sound on

MQTT messages:

• doorBellTopic = "doorBellGW/doorbell" --> issued when pushbutton pressed: trigger / re-trigger / release
• postboxFlapTopic = "doorBellGW/mailboxFlap" --> issued, when flap is opened to enter mail: trigger / re-trigger / release
• postboxDoorTopic = "doorBellGW/mailboxDoor" --> issued, when mailbox door is opened to remove mail: trigger / re-trigger / release
• doorBellTriggerSoundTopic = "doorBellGW/doorbellTrigger" --> listens to this message and turns on relay for a short time to trigger the bell/gong
• doorLightRequestTopic = "doorBellGW/lightRequest" --> issued, when light pushbutton is pressed: trigger / re-trigger / release; light is turned on for 30 seconds
• postboxLightTopic = "doorBellGW/light" --> listens to this message and turns light on at mailbox for 30 seconds
• postboxLightStatusTopic = "doorBellGW/light/status" --> issued, when light at mailbox is turned on/off: on / off