Best Practices for Building an IoT Data Logger with STM32

[tauqirashraf]

Hi everyone,

I'm planning to build an IoT-based data logger using an STM32 microcontroller and would appreciate some advice from those who have worked on similar projects.

The project requirements include:

• Reading multiple environmental sensors (temperature and humidity)
• Logging data to an SD card
• Sending data to a cloud platform via Wi-Fi or LTE
• Low power consumption for long battery life
• Ability to update firmware remotely in the future

I'm currently considering the STM32L4 or STM32U5 series because of their low-power capabilities, but I'm open to suggestions if another family would be more suitable.

A few questions:

• Which STM32 series would you recommend for this type of application?
• Is STM32CubeMX sufficient for managing a project of this size, or would you recommend another workflow?
• Have you used FreeRTOS for sensor reading, data logging, and communication tasks? Was it worth the added complexity?
• Are there any common pitfalls I should watch out for when designing the hardware or firmware?

I'd really appreciate hearing about your experiences, recommendations, or lessons learned from similar IoT projects.

Thanks in advance!

[mƎALLEm]

Hello,

• Which STM32 series would you recommend for this type of application?

You can start evaluating STM32U5 using this board: Discovery kit for IoT node with STM32U5 series

Similar board with STM32L4 is NRND: B-L475E-IOT01A (Not Recommended for New Design)

 

 

[Andrew Neil]

• Reading multiple environmental sensors (temperature and humidity)

 How many?

 

• Sending data to a cloud platform via Wi-Fi or LTE
• Low power consumption for long battery life

Neither of these is particularly low power.

Why do you feel the need for WiFi or LTE?

For low power, you would generally go for much lower bandwidth options; eg, LoRa, NB-IoT, Cat-M ...

 

Is STM32CubeMX sufficient for managing a project of this size

Not sure what you mean by this?

CubeMX isn’t really about “managing” a project.

It’s just about allocating pins, and creating the initialisation code.

 

• Have you used FreeRTOS for sensor reading, data logging, and communication tasks? Was it worth the added complexity?

You shouldn’t need an RTOS for this.

 

• Are there any common pitfalls I should watch out for when designing the hardware or firmware?

Best way to low power is generally to have the system sleep for as long as possible.

Be sure to keep testing this throughout the development...