Using Multiple Memory Regions with the FreeRTOS Heap

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 with Segmented Heap Memory

Continue reading

WiFi OLED Mini Weather Station with ESP8266

I’m convinced that this ‘Internet of Things’ thing-thing is not real. Pure marketing and buz words without any added value, right? The IoT hype is so bizar: it must be originated by aliens which have taken over the brains of all the Pointy-haired Bosses of the world? There is no useful application or use case out there!

But wait! There *is* actually good use case, at least for the geeks of this world. We all love clocks as we want to know the time, and we all love the weather forecast so we can plan accordingly. At least I usually do :-).

SQUIX ESP8266 Mini Weather Station

SQUIX ESP8266 Mini Weather Station

Continue reading

Using the GNU Linker Script to know the FLASH and RAM Areas in the Application

Sometimes it is handy to know in the running application the start address, end address and the size of a linked section, e.g. to know the boundaries of RAM or FLASH areas. This means that from the application code I can get access to knowledge of the GNU linker:

Information about Linker Sections

Information about Linker Sections

Continue reading

Recovering and Updating the NXP OpenSDA Bootloader with P&E Multilink and MCUXpresso IDE

Many of the NXP OpenSDA boot loaders are vulnerable to Windows 8.x or Windows 10: write accesses of Windows can confuse the factory bootloader and make the debug firmware and bootloader useless. In this post I show how to recover the bootloader using MCUXpresso IDE and the P&E Universal Multilink.

Using P&E Multilink Universal to restore the OpenSDA Bootloader on NXP FRDM-K22F Board

Using P&E Multilink Universal to restore the OpenSDA Bootloader on NXP FRDM-K22F Board

Continue reading

Tutorial: Porting BLE+NRF Kinetis Design Studio Project to MCUXpresso IDE

The tools and IDE market is constantly changing. Not only there is every year at least one new major Eclipse IDE release, the commercial tool chain and IDE vendors are constantly changing the environment too. For any ARM Cortex-M development, the combination of Eclipse with the GNU tool chain provided by ARM Inc. is the golden standard. But this does not mean that things can be easily moved from one IDE package to another.

While moving between Eclipse versions and GNU versions is usually not a big deal at all, moving between the Eclipse build tool integration is usually not simple. While the GNU MCU Eclipse plugins are widely used (see Breathing with Oxygen: DIY ARM Cortex-M C/C++ IDE and Toolchain with Eclipse Oxygen), the Eclipse based IDEs from the silicon vendors or commercial Eclipse toolchain vendors are using  their own GNU toolchain integration. Which means the project files are not compatible :-(.

NXP FRDM-KW41Z Board

NXP FRDM-KW41Z Board

Continue reading