One of the great things with the FreeRTOS operating system is that it comes with free performance analysis: It shows me how much time is spent in each task. Best of all: it shows it in a graphical way inside Eclipse too:
Doing Mini Sumo robot competition is really fun, and there is yet another one coming to end the current university semester. For several years we have used our own sumo robot, and this is the one used in the course this year too. But for future and extended events we are exploring a new robot. I proudly present the concept of the next generation sumo robot for the year 2018:
Back in March 2017, NXP had rolled the MCUXpresso IDE starting with Version 10.0.0. With the intent to unify the SDK, LPCXpresso, CodeWarrior, Kinetis Design Studio and Processor Expert into one unified and integrated set of tools. V10.0.0 was a good start. The MCUXpresso IDE V10.0.2 in July was more of a smaller update, and the Pin and Clock configuration tools were not integrated, no added tool for peripheral configuration.
A week ago the MCUXpresso V10.1.0 has been released which shows where the journey is going: an free-of-charge and code size unlimited Eclipse based integrated set of tools to configure, build and debug Cortex-M (Kinetis, LPC and i.MX RT) microcontroller/processor based applications.
I have used it for a week, and although many things are still new, I thought I’m able to give an overview about what is new.
I’m using many microcontroller in my projects. And a lot more are available out there in the ecosystem. Like many others, I tend to select what I am familiar with. But is this the correct approach to select the hardware and tools for a next project?
I’m pleased to announce that a new release of the McuOnEclipse components is available in SourceForge. In this release more ARM Cortex devices/vendors are supported with different SDKs, plus it comes with several FreeRTOS enhancements for debugging highly optimized code.
ARM Cortex-M microcontrollers can have multiple memory controllers. This is a good thing as it allows the hardware to do multiple parallel memory read/writes. However this makes the memory map more complicated for the software: it divides the memory into different regions and memory segments. This article is about how to enable FreeRTOS to use multiple memory blocks for a virtual combined memory heap:
Eclipse as IDE takes care about compiling and building all my source files. But in an automated build system I would like to build it from the command line too. While using make files (see “Tutorial: Makefile Projects with Eclipse“) is an option, there is another easy way to build Eclipse projects from the command line:
Last month (June 2017), the latest version of Eclipse “Oxygen” has been released, and I have successfully used it in several embedded projects. Time to write a tutorial how to use it to build a custom Do-It-Yourself IDE for ARM Cortex-M development: simple, easy, unlimited and free of charge. While the DIY approach takes a few minutes more to install, it has the advantage that I have full control and I actually know what I have.
I love 3D printing as it enables me to create custom enclosures for all kind of projects. The NXP LPC-Link2 probe is great, but it lacks a protective enclosure. So I decided to create a custom enclosure. And as 3D filaments are available in different colors, I experimented with red and black and custom painting:
FreeRTOS seems to get more and more popular, and I think as well because more and more debugger and Eclipse IDE vendors add dedicated debugging support for it.
By default, the GNU Linker expects a very special naming scheme for the libraries: the library name has to be surrounded by “lib” and the “.a” extension:
But what if the library I want to use does not conform to that naming standard?
The benefit of an IDE like Eclipse is: it makes working with projects very easy, as generates make files and it takes and automatically manages the make file(s). But sometimes this might not be what I want because I need greater flexibility and control, or I want to use the same make files for my continues integration and automated testing system. In that case a hand crafted make file is the way to go.
One thing does not exclude the other: This article explains how to use make files with Eclipse with similar comfort as the managed build system in Eclipse, but with the unlimited power of make files:
NXP has released an updated of their Eclipse based IDE for ARM Cortex-M (Kinetis and LPC) microcontroller: the version v10.0.2 build 411:
If you are like me – someone who always wants to know what the compiler generates for a piece of source code – then have a look at the Compiler Explorer: A web-based compiler code comparison tool:
Thanks to Matt Godbolt, I can select different compilers and compare their output for a given source code. Very useful to see the impact of a compiler optimization or to compare different GCC compiler versions.
Happy Comparing 🙂
For reliable applications, I avoid using functions of the standard libraries. They are banned for most safety related applications anyway. I do not use or avoid
printf() and all the other variants, for many reasons including the ones listed in “Why I don’t like printf()“. Instead, I’m using smaller variants (see “XFormat“). Or I’m using only the thread-safe FreeRTOS heap memory allocation which exist for many good reasons.
Things get problematic if
malloc() still is pulled in, either because it is used by a middleware (e.g. TCP/IP stack) or if using C++. Dave Nadler posted a detailed article (http://www.nadler.com/embedded/newlibAndFreeRTOS.html) about how to use newlib and newlib-nano with FreeRTOS.
In “Cycle Counting on ARM Cortex-M with DWT” I have used the ARM DWT register to count the executed cycles. With the MCUXpresso IDE comes with a very useful feature: it can capture the ARM SWO (Single Wire Output) trace data. One special kind of trace data is the ‘cycle counter’ information which is sent through SWO.
Eclipse for C/C++ (CDT) offers two different ways to get out of a debug session: Terminate and Disconnect:
The terminate and disconnect behaviour is not standardized, and varies between Eclipse distributions and debug connection. This article is about how things are handled in MCUXpresso IDE, and how I can influence the behaviour.