The revised implementation of the publish_aws_iot_payload() function establishes a persistent MQTT connection over TLS, enabling ongoing telemetry message transmission without repeated handshake processes. By keeping the connection alive and sending PINGREQs as needed, the firmware enhances efficiency and reliability, with successful communications verified on the STM32U5 board.
This project focused on integrating AWS IoT Core with the B-U585I-IOT02A board. Initial tests validated sensor data transmission over TLS using an Ubuntu client before transitioning to STM32. Successful telemetry publishing was achieved with the implementation of mutual TLS, ensuring secure MQTT communication with AWS IoT Core. Future improvements will enhance connection persistence.
The post details the process of connecting the B-U585I-IOT02A development board to AWS IoT Core after successfully publishing sensor data to a public Mosquitto broker. Key steps include creating an AWS Thing, generating an X.509 certificate, and formulating a restricted MQTT policy. The project will advance to adding TLS support for secure communication.
This blog outlines the development of a cloud-connected sensor node using the STMicroelectronics B-U585I-IOT02A Discovery Kit. The project combines a custom bootloader in C with Rust firmware for data acquisition and cloud integration via AWS IoT Core, providing a comprehensive engineering guide from hardware setup to data visualization.