Using IP (Ethernet) based debug probes is a very handy thing: I don’t have to be directly connected to the debug probe (e.g. with the USB cable). This article explains how to use an IP-based Segger or P&E probe with the Eclipse based MCUXpresso IDE.
Windows 8 and 10 have added a ‘feature’ to scan and index devices attached to the host machine. This means that bootloaders or MSD (Mass Storage Device) programming implementations on evaluation boards developed in the Windows 7 age might not be prepared for that. Up to the point that it can impact the bootloader as outlined in “Bricking and Recovering OpenSDA Boards in Windows 8 and 10“. So far one of the easiest way to get out that situation was to use a Windows 7 machine. But if you only have a Windows 10 machine available, this article describes the needed steps to update the bootloader with Windows 10 host machines.
The map file produced by the GNU linker includes lots of information, however it is very cryptic to read. In “Listing Code and Data Size for each Source File with GNU and Eclipse” I showed how the GNU size utility can be used to report the code and data size for each object file. The Eclipse based MCUXpresso IDE comes with another nice view which shows detailed information about code and data allocation:
In “Flash-Resident USB-HID Bootloader with the NXP Kinetis K22 Microcontroller” I presented how I’m using the tinyK22 (or FRDM-K22F) with a flash resident USB HID bootloader. To make sure that the loaded application is not corrupted somehow, it is important to verify it with a Cyclic redundancy Checksum (CRC). The NXP KBOOT Bootloader can verify such a CRC, but how to generate one and how to use it is not really obvious (at least to me), so this article explains how to generate that CRC.
Right before the start of the new semester, the new tinyK22 boards (see “First tinyK22 Board with NXP K22FN512 ARM Cortex-M4F“) arrived, and they are looking great 🙂
In “Eclipse MCUXpresso IDE 10.1 with integrated MCUXpresso Configuration Tools” I mentioned that I wanted to try the i.MX RT1050 processor. Well, finally my ordered board from Mouser arrived, right on time for the week-end, so I had a chance to use that ARM Cortex-M7 running at 600 MHz :-).
“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.
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.
The ARM mbed USB MSD bootloader which is used on many silicon vendor boards has a big problem: it is vulnerable to operating systems like Windows 10 which can brick your board (see “Bricking and Recovering OpenSDA Boards in Windows 8 and 10“). To recover the board, typically a JTAG/SWD programmer has to be used. I have described in articles (see links section) how to recover from that situation, including using an inofficial new bootloader which (mostly) solves the problem. The good news is that ARM (mbed) has released an official and fixed bootloader. The bad news is that this bootloader does not work on every board because of a timing issue: the bootloader mostly enters bootloader mode instated executing the application.
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:
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 :-(.
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.
Sometimes it happens that arm-none-eabi-gdb complains about “no source file named” in the GDB console view in Eclipse when I debug a project with GDB:
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:
A bootloader on a microcontroller is a very useful thing. It allows me to update the firmware in the field if necessary. There are many ways to use and make a bootloader (see “Serial Bootloader for the Freedom Board with Processor Expert“). But such a bootloader needs some space in FLASH, plus it needs to be programmed first on a blank device, so a JTAG programmer is needed. That’s why vendors have started including a ROM bootloader into their devices: the microcontroller comes out of the factory with a bootloader in FLASH. So instead writing my bootloader, I can use the one in the ROM.
And as with everything, there are pros and cons of that approach.
For a research project, we are going to send a satellite with an embedded ARM Cortex microcontroller into space early next year. Naturally, it has to work the first time. As part of all the ESA paperwork, we have to prove that we tested the hardware and software thoroughly. One pice of the that is to collect and give test coverage evidence. And there is no need for expensive tools: Free-of-charge Eclipse and GNU tools can do the job for a space mission 🙂