If you are a regular reader of my articles, you probably know that I’m using FreeRTOS in most of my applications, for obvious reasons. But clearly this is not the only RTOS out there. After Microsoft had acquired Express Logic back in April 2019 things kept quite for a while. To me the crown jewel of Express Logic is the ThreadX RTOS. But recently Microsoft is pushing more and more the ‘Azure Sphere’ and trying to monetize the ‘IoT’ (I apologize for mentioning that overused acronym) application space and providing it now free for devices from selected partners which includes NXP now.
Category Archives: ARM
Debugging Bootloader and Application with one Debug Session
If having a boot loader running on a micro-controller, it is very useful if both the boot loader and the loaded application can be debugged together:
tinyK22 Board Rev 1.3 released
The tinyK22 board is a tiny micro controller board we use at the Lucerne University of Applied Sciences and Arts. It is used in many research project, used in lectures and labs and used in most student projects. Because there was no small and breadboard friendly NXP Kinetis board with a debug interface available, we developed one featuring the NXP K22FN512, named the ‘tinyK22‘. Because of the success and high demand we stated a new large production run and used this to upgrade the board to the new Rev 1.3: you might notice already the color change :-).
MCUXpresso IDE V11.2.1
I have started the semester and labs using the MCUXpresso IDE V11.2.0 which has been available from July this year. The past week I received the notification that the update V11.2.1 is available: time to check it out….
FreeRTOS V10.4.1 with SEGGER SystemView V3.12
Amazon has released in the past week the FreeRTOS version V10.4.0. Time to upgrade, actually the most recent version 10.4.1! The same time the SEGGER SystemView V3.12 was released back in April this year. No surprise: with the FreeRTOS changes they don’t work out of the box: but no worries, I have you covered and applied all the needed patches and changes to have them working again together: the latest FreeRTOS v10.4.x with Segger SystemView v3.12:
DIY Portable Video Conference, Sharing and Teaching Device
COVID-19 is by far not over, and in Switzerland the infection rate is going up again (2nd wave?). During the spring 2020 semester university lock-down we moved pretty much everything to a ‘distance learning’ setup. With that experience and with the request to prepare for the fall semester, I have constructed a DIY conference and teaching device which should make things simpler and easier: a combination of video camera, speaker phone and a muting device:
MCUXpresso IDE V11.2.0
At the university the end of a semester means that you have to get ready for the next semester. I always tend to use the latest and greatest tools for the labs. This week I received the notification that a new version of the Eclipse based MCUXpresso IDE is available, time to check it out for the next semester.
From C to C++: Converting Eclipse C Projects
Creating a new project with Eclipse for a microcontroller these days is fairly easy, and I have the choice if I want to start the project with C or C++:
Still the embedded microcontroller world is dominated by C and not C++. So while it is easy to start with a C++ project, most vendor provided example or tutorial project are C projects. So how can I transform such project to C++?
MCUXpresso SDK Tutorial – using I2C Driver on OKdo E1 board
In an earlier tutorial I introduced using I2C with the NXP LPC55S69 on OKdo E1 board to read a Bosch BME280 environmental sensor on a Mikroe Weather Click board. The MCUXpresso Clocks, Pins and Peripheral Config tools were used to get it running. It’s all for my Weather Station project that I’ve been working on during these months of lockdown. It is starting to take shape – as you can see from the photograph:

Now I really need to start reading and writing to the BME280 sensor, and that means using the I2C driver in the lpcxpresso55s69 SDK. And so this week I’ll provide a forensic examination of the most commonly-used I2C function call.
Continue readingMicroTick (UTICK) Timer Tutorial with OKdo E1 board
I want to share with you a little embedded trick that I use to improve the reliability of my code. And in addition to improving reliability, the technique can be used to schedule any event to occur ‘sometime in the future’. It uses the MicroTick (UTICK) timer found on the NXP LPC55S69 microcontroller, and could be applied to any device with a simple timer.
The MicroTick timer is an elegant, thing of beauty. But there is not a driver example built into the lpcxpresso55s69 SDK, and I believe that the timer is not widely used. That means we need a tutorial!
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