This topic describes how to use device SDK for C to connect a bare-metal microcontroller device to IoT Platform by using Message Queuing Telemetry Transport (MQTT).
Implementation
Connect an MCU to a communication module and use AT commands for communication between the MCU and the communication module. Use device SDK for C to connect the communication module to IoT Platform and enable communication between each other.

Prepare software and hardware
You must prepare the following items.
- A NUCLEO-F103RB demo board that is equipped with an STM32F103 MCU from ST.
- An SIM800C mini V2.0 demo board that is equipped with a SIM800C communication module from SIMcom.
- The IAR Embedded Workbench for ARM development environment.
Procedure
Create a product and add a device