The year 2022 is coming to an end, and I have spent some time today on a little side project. It is about making an Electrical Vehicle (EV) wallbox charger accessible over Modbus RTU. It is not finished yet, and I plan to publish more articles on it, but I can share that I’m able to access and control the Heidelberg EV charger with a Raspberry Pi Pico W (Dual Core Cortex M0+), NXP K22FN512 (Cortex M4F) and LPC845 (Single Core Cortex M0+):
It is already December 1st, and time for a new Advent Calendar. This year the design includes birch plywood with PMMA, SK6812 RGBW LEDs running with a Raspberry Pi Pico board, building a small village.
In many embedded applications, it is mandatory that memory allocation is static and not dynamic. Means that no calls to things like malloc() or free() shall be used in the application, because they might fail at runtime (out of memory, heap fragmentation).
But when linking with 3rd party libraries or even with the C/C++ standard libraries, how to ensure no dynamic memory is used? The problem can occur as well for C++ objects, or a simple call to printf() which internally requires some dynamic memory allocated.
Continue readingIn this time where many micro-controllers have 100+ weeks estimated delivery time, it makes sense to look at alternatives. So it is not a surprise that the Raspberry Pi RP2040 gets used more and more in projects. It is not only inexpensive, it is (at least for now) available which makes all the difference. The RP2040 is the first microcontroller from Raspberry Pi: a dual-core ARM Cortex-M0+ running up to 133 MHz, 264 KByte on-Chip RAM and up to 16 MByte external FLASH.
It is a very versatile microcontroller, with a rich eco-system and set of tools. It can be easily used with C/C++ or MicroPython, and the Raspberry Pi Pico board only costs around $5. There are plenty of tutorials out there, for example how to use the Pico board as debug probe to debug another Pico board. While this is great, there is an easy way to use any existing J-Link and Eclipse IDE too, so this is what this article is about.
Continue readingOne great thing with the Eclipse Gnu Make Builder (aka ‘auto make’ or ‘auto build’) feature: just add source files (*.c, *.cpp, …), and with kind of magic, they all get compiled and linked properly.
But for something easy and convenient: is it hard to use custom file extensions? So what if I want to use a different file extension for my source files, different from the standard ones? Actually Eclipse CDT can do this too, it just takes two settings to recognize, compile and link source files with custom extension.
Split-flap displays are electromechanical display devices, which were common in airports or railway stations a few years ago.Unfortunately, most of them are gone and replaced by LED displays. Why not create a DIY version of it?
I’m pleased to announce a new release of the McuOnEclipse components, available on SourceForge. This release includes several bug fixes, support for more devices, and updated components like FreeRTOS, MinINI, Percepio Tracealyzer and SEGGER SystemView.
SourceForge
Many embedded systems application need to store some kind of data in a persistent way: calibration values, settings or log information. For a smaller amount of data, using an external memory or file system is an overkill. In many system I’m using minINI to store key-value pars in in a ‘ini-file’ way, but it requires the use of a file system of some kind. minINI is great and efficient, and makes getting and storing data really easy. But for simple cases, a single FLASH memory page or sector is just all what I need. Instead managing that page directly, why not using minINI without a file system?
Header files in C/C++ are defining the interface between different modules. In this article I share some tips and tricks how create such interface files.
It is interesting to see that some aspects (mostly unintended) can stimulate lots of good and fruitful discussions. So this happened with “Spilling the Beans: Endless Loops” (recommended to read 🙂 where using (or not using) volatile for inline assembly created thoughts which warrant an article on that subject.
The volatile qualifier in C/C++ is misunderstood by many programmers, or wrongly used.
Still, ‘volatile’ is very useful if you know what it means for the compiler and what is good use of it.
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MCU on Eclipse 