ja2mqtt is a bridge that connects a Jablotron control unit, extended with the [JA-121T RS-485 bus interface](https://www.jablotron.com/en/produkt/rs-485-bus-interface-426/), to an MQTT broker.

ja2mqtt enables the use of MQTT events to control Jablotron events, allowing for seamless integration with MQTT-based IoT systems and platforms. With this bridge, Jablotron alarms can be integrated into a larger IoT ecosystem, alongside other devices that use industry-standard protocols like ZigBee or MQTT. For example, by using ja2mqtt in conjunction with ZigBee2MQTT, Jablotron alarms and ZigBee devices can be connected in a single network and integrated with other systems such as Alexa, Tahoma, or Google Assistant, providing a unified and interoperable smart home or industrial automation solution.

ja2mqtt reads input from the JA-121T serial interface, converts it into MQTT events, and publishes them to the MQTT broker using defined MQTT topics. It utilizes a ja2mqtt definition file that outlines the implementation of the JA-121T protocol. Additionally, ja2mqtt defines MQTT events that can be converted into input for the JA-121T serial interface, such as changing the state of a section to ARMED or READY. Each MQTT request may contain a correlation ID that is copied to the corresponding generated MQTT event.

If you do not have access to a JA-121T interface for testing, ja2mqtt offers a simulator that can simulate the interaction with the JA-121T interface. This allows you to test and verify the functionality of ja2mqtt even without the physical JA-121T interface available.

See https://github.com/tomvit/ja2mqtt for more details.

