You can have a product based on a microcontroller and operating fully offline, for example, a washing machine. But you’d now like to update your appliance to connect to the cloud so it can upload data to the cloud, and help your customer access it.
This is a non-trivial update as it requires you to add a communication module be it WiFi or Ethernet, or a new microcontroller that would require you to update your firmware to support networking and other new features. You’d also need to develop your own cloud platform, and potentially a smartphone app.
Cesanta VCON platform aims to simplify the upgrade with firmware that can be flashed to ESP8266 or ESP32 module, and remotely upgrade the firmware on STM32 and AVR microcontrollers.
On the hardware side, you’d need to wire your existing MCU to the ESP32 module with UART for data, BOOT/RESET for OTA firmware update. You don’t need to update your existing firmware at this point, simply flash the latest VCON firmware to the provided ESP32 module, configure networking and cloud login, and you can update your MCU firmware over the mDash IoT Cloud service using Websocket or REST. You’ll just need to add new features to your firmware that will send data over UART to VCON module.
The company provides a detailed Wiki showing how to get started with either ESP32 or ESP8266 boards/modules connected to AVR based Arduino Nano, or STM32 powered BluePill board. There’s also mDash documentation with details about the API needed to interact with the cloud and the development of Android/iOS mobile apps.
VCON firmware is always free, while mDash IoT cloud service is free for up to 10 devices, and costs $49 per month for up to 500 devices, and if you need to support more you’ll get a customized quote, support for firmware development.