I’m pleased to announce a new release of the McuOnEclipse components, available on SourceForge. This release includes several bug fixes, extra support for the NXP S32 Design Studio and SDK and includes FreeRTOS V10.1.1.
SourceForge
The McuOnEclipse GitHub repository hosts many Processor Expert projects and is very popular (cloned more than 1000 times, thank you!). Processor Expert is a powerful framework which generates driver and configuration code, simplifying application development for a wide range of microcontroller and families. But Processor Expert won’t be developed further by NXP and is not part of MCUXpresso IDE. While it is possible to install Processor Expert into MCUXpresso IDE 10.2, how can these projects used ini an IDE *without* Processor Expert? This article describes how to port an existing Processor Expert project into the NXP MCUXpresso IDE.
Ported Project with FRDM-K64F using Adafruit SSD1351 and Processor Expert
In “Tutorial: FreeRTOS 10.0.1 with NXP S32 Design Studio 2018.R1” I showed how to use a custom FreeRTOS with the S32 Design Studio (ARM). The OSIF (OS Interface) provides an operating system and services abstraction for the application which is used by other S32K SDK components:
OSIF in S32K for ARM Eclipse Project
NXP not only sells general purpose microcontroller, but as well a portfolio of automotive devices which includes the S32K which is ARM Cortex based. For this device family, they offer the S32 Design Studio (or S32DS) with its own Eclipse distribution and SDK. The interesting part is that the S32DS includes Processor Expert (which is a bit different from the ‘mainstream’ Processor Expert). It comes with its own components for the S32K SDK which includes a component for FreeRTOS. But that component in S32DS 2018.R1 comes with an old V8.2.1 FreeRTOS component:
FreeRTOS 8.2.1 in S32DS 2018.R1
So what to do if I want to use the latest FreeRTOS (currently 10.0.1) with all the bells and whistles?
I’m pleased to announce that a new release of the McuOnEclipse components is available on SourceForge. This release includes several smaller bug fixes and initial component support for the NXP S32 Design Studio and SDK.
SourceForge
Hardware Timers are essential to most embedded applications: I use them mostly for triggering actions at a given frequency, such as acquiring data from a sensor. With using an RTOS I can do a similar thing using a task: the task will run with a given frequency and I can periodic work in it. However, using a task might be too much overhead doing this. The good news is that there is a much more efficient way to do this in FreeRTOS with Software Timers. And this is what this tutorial is about: how to use Software Timers with FreeRTOS.
FreeRTOS Software Timers
When using the FreeRTOS Task List in the Eclipse based MCUXpresso IDE, it shows the list of tasks with their stack size used. But with the default FreeRTOS settings it is not able to determine the correct stack size and shows a warning icon:
Warning for Stack Usage
I apologize: I have not been blogging much in the past weeks :-(. One reason is that I’m working on a DIY SMT/SMD Pick&Place machine which keeps me busy most of my spare time :-). I admit that this project is not finished yet, but now is the time I can give a sneak preview: a SMD/SMT pick and place machine:
Pick&Place Machine
It’s April Fool’s Day, but be assured this is not a joke ;-): I’m pleased to announce that a new release of the McuOnEclipse components is available in SourceForge. This release includes several smaller bug fixes and components have been upgraded for FreeRTOS V10.0.1.
SourceForge
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:
FreeRTOS Runtime Information in Eclipse
To solve the real hard problem of Embedded Systems development, I usually need all the data I can get from the target. The Percepio Tracealizer is such a tool which can stream application and FreeRTOS trace from the target over a Segger J-Link connection using the Segger RTT protocol. I’m using that combination a lot.
Streaming trace data that way does not need a dedicated hardware like ETM Trace. Using RTT is usually not much intrusive and affects the performance of the target in the 1-2% range (of course depending on the amount of data).
But what worried me for several weeks is that after moving to FreeRTOS V10.0.0 and the same time updating the Segger libraries, the target performance was heavily affected:
RTT streaming affects target performance?
I’m pleased to announce that a new release of the McuOnEclipse components is available in SourceForge., which is supposed to be the last release for 2017 :-). This release features several smaller bug fixes, the new FreeRTOS V10.0.0 and extended device support.
SourceForge
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:
Sumo Robot with Bluetooth module
“Amazon FreeRTOS – IoT operating system for microcontrollers”: The announcement of FreeRTOS V10.0.0 was one of the biggest news last week for me. Not only is there now a Version 10, the bigger news is that FreeRTOS is now part of Amazon. Wow! Now this explains why Richard Barry (the founder behind FreeRTOS) was kind of hiding away for about a year: he joined Amazon as a principal engineer about a year ago. I think we all have to wait and see what it means for FreeRTOS.
Amazon FreeRTOS (Source: Amazon Web Site)
The NXP Freedom boards are very popular. Many of them are inexpensive (less than $20), include a debug interface and can be easily extended with extra shields or boards. Especially the FRDM-KL25Z is very popular: I’m getting told because of Processor Expert and tutorials available on web sites like this one ;-).
Unfortunately there are no small or breadboard friendly Kinetis boards available. There is the NXP LPC800-DIP but with no onboard debugger and without Processor Expert support. We have the tinyK20, but projects tend to use more CPU power, FLASH and RAM space than what the tinyK20 board (50 MHz, 128 KByte FLASH, 16 KByte RAM) can provide. So we ended up designing the big brother of the first tinyK20: the tinyK22 with 120 MHz, 512 KByte of FLASH and 128 KByte of RAM.
tinyK22 Overview
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.
SourceForge
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:
FreeRTOS with Segmented Heap Memory
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.
FreeRTOS Threads in Eclipse
I’m pleased to announce that a new release of the McuOnEclipse components is available in SourceForge, with the following major changes and updates:
SourceForge
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 malloc(), 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.
FreeRTOS Newlib Memory Allocation Scheme
