Tag Archives: STM32

STM32 RTC Clock downsides and backup domain registers

The title for this blog can be a bit misleading but let me assure that all these three things have something in common. The RTC clock allows you to measure real time and by assumption this measurement should be very precise. And the key word is assumption because depending on what kind of clock source you will chose you can get completely different results. All of it is dependent on the clock source, thus the internal oscillator. Additionally, since RTC shares the same special register space I will also discuss so-called backup registers. Let us get started.

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My quadrocopter adventure

Well, I feel like this will be one of these sentimental entries, but not entirely. I would like to present my journey with quadrocopters, or drones in general. I first started to invest in drones when I was at my university. The passion developed in 2012 when I was defending my Bachelor’s degree and I decided to make a thesis about it. The topic was ‘Filtering and validation of measurements from accelerometer and gyroscope in Matlab/Simulink for a quadrotor flying robot’. In this blog post, I will tackle different aspects, namely software and hardware (mechanics and electronics).

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RemoteLab a distributed Hardware-as-a-Service

This blog will be a little bit different from what I usually write about but not entirely. I am very proud of the results of what I did and I would like to share them with you. It is not a secret that I work at Wrocław University of Science and Technology. Apart from my research duties, I also run classes with my students. However, we should start the story from the beginning, that is, in the year 2019. At the dawn of 2019 we had COVID-19 outbreak. It did a lot of change in our lives and daily duties which still ought to be carried out. From the perspective of my university there were a lot of challenges. The lectures could be moved to the digital world pretty easily; however, project or laboratory classes were not that easy to move. They strongly depend on human-to-human interaction, and additionally when you work with hardware, it is even more challenging. What I did and what I will describe below was a way to respond to these difficulties. It involves a lot of hardware and not a small dose of software development.

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nRF905 — an another module for wireless communication

You might be already familiar with different transceivers I have described here, namely LoRa module. You can read about it here (STM32 driver for LoRa) and here (Raspberry Pi driver for LoRa). Now, time have come to give nRF905 module a try. As usually, the driver alone and an example are available at my github. If you do not want to read the rest of this blog, just jump straight to nRF905 driver or the example.

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ADC is as fast as possible always the best approach?

Is as fast as possible always the best way to do things with STM?

Recently, I have stumbled upon an issue regarding ADC scan conversion on STM32 microcontrollers. I have wondered why the scan conversion was not taking place. As it turned out it did but it was not handled fast enough. In this blog post I will discuss the need to return from interrupt routine as fast as possible. However, it will not be only this one thing. Interested? So keep reading.

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ADC initialization order bug in CubeMX

An another bug in STM32CubeMX software. This is a perfect example where the order of called initialization functions really matters. In discussed case I will give an example where ADC was configured to go through regular conversion triggered by an event from timer and the data was transferred automatically using DMA.

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Pan Tilt Camera for Raspberry Pi with STM32 and UV4L

I would like to present a simple project which involves Raspberry Pi with a camera. Sounds boring, right! But the camera can be tilted in two axis using two servos which are directly controlled via STM32 microcontroller which in turn communicates with Raspberry Pi. Furthermore, the RPi is hosting a web server with interface to control position and speed of the camera and of course the video is streamed so you can see what is going on i.e. in your room. If you are even a bit intrigued then keep reading.

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Design of embedded system

Today, I would like to ponder on a subject of creating some measurement systems, or in more general, embedded systems. There are multiple approaches to make such a system. Let’s consider a few of them — the most popular approaches.

Embedded systems are gaining popularity by the day. Those systems are used in Internet of Things (IoT) but also in more advanced control systems. However, sometimes a need of more sophisticated system is emerging which requires more computational power. I would like to present some architectures of such systems and highlight some features of those approaches.

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ST-Link-V1 — Obsoleted but not depreciated

Yes, I am still using the practically obsoleted ST-Link-V1 on a STM32F1 disco board. It still gets the job done but regretfully it is not supported out of the box by IDE I happen to use from time to time.

When I gave a try to the AC6 (SW4STM32) I found out that, to not much of a surprise, the ST-Link-V1 is not supported. Only V2 and V2.1 are supported. Well, I decided to change that unfortunate situation because I have two of the disco boards with this debugger laying around.

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SPL vs HAL: which one should you use (and Low Layer Library) — part 2

stmcube_import_step1

Some time ago I have written SPL vs HAL: which one should you use where I have focused on differences between two main frameworks for STM32 — Standard Peripheral Library (SPL) and Hardware Abstraction Layer commonly known as HAL. Since the recent post only focuses on those two sets of libraries I have decided to write some examples which can tip the scale. What is more, at the end of previous article I have asked an important question for a developer — does the STM is going to introduce us to a brand new library. Answer to this and other questions are further in this post.

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STM32 HAL driver for I2C OLED display with U8glib

oled_display_ssd1603

Recently, I have come to a conclusion that it would be good to print the state of my quadrocopter on a display. The question was what kind of display should I use. I decided to give a try to a small 0.96″ OLED display with I2C interface. It is based on SSD1603 driver. You can see this display on the image above. However, there was an issue regarding the screen controller. But it was soon solved. I have come across the U8glib which is a graphic library, quite popular among Arduino users. As soon as I started to read about the library I realized that it does not support STM32, not mentioning the HAL library.

Well, I have solved that 😉

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