Solar panels and electrical vehicles become more and more common in Switzerland. Ten years ago I installed solar panels. To use the available solar energy, the electrical vehicle charging box has been augmented with an open source charge controller. The controller monitors the building energy usage and adjusts the current using the Modbus connection to the charger.
We have a project imported, have built it, time to debug it on the hardware.
Don’t worry: despite all the things going on with VS Code, Eclipse is here to stay probably for many more years. The Eclipse foundation is pumping out releases, and so does NXP with their latest MCUXpresso IDE 11.8.0. Lets have a look…
I’m using the RS-485 field bus in many of my projects: it is very reliable and robust, and easy to implement. And with ModBus there is standardized protocol used in building automation or industrial control applications. For example I’m using the protocol to communicate between battery systems and an EV Charger.
In this article I show you with an example, how the NXP LPC55S69 can be used with RS-485.
Continue readingIt is August 1st, and Switzerland is celebrating its National Holiday. Rather cold and rainy, so this gets me some time to catch up on things. The preparation for the coming university semester in September is in full swing, and I have the honor to take over building up a new Master of Science in Engineering education module. In the existing courses I teach on the topic of embedded systems, I do use devices and MCUs from vendors like Broadcom, NXP, STM, Nordic, Raspberry Pi and Espressif. This not only means different SDKs, but different IDEs with different debug probes.
Eclipse has been the common factor in the mix with all these, and with all the pros and cons, it worked very well. With NXP having released support for Visual Studio Code, adding an announcement, and other vendors going into the same direction, I took the decision that I want to migrate my lab and lecture infrastructure to VS Code.
Continue readingThe Freescale K20DX128 MCU was one of the first ARM Cortex-M devices of that company (now NXP) back in 2012, and the FRDM-K20D50M board was the first ‘FRDM‘ board of a long and successful series of boards, starting back in 2013. I still have the K20 present in many of my designs. The challenge with ‘early’ or ‘legacy’ devices is that after a while, they are ‘not recommended’ any more, and it is hard to get support for them. So for example in newer tooling and software from NXP, there is no support for the K20.
So if you still have the K20 around, and need some newer tooling, then I have good news for you: It is possible to add that good-old-Kinetis to the list of supported LinkServer devices, so you are not stuck and can use newer debugging solutions for the K20.
Continue readingThe MCU-Link is an inexpensive CMSIS-DAP debug probe from NXP. It can be used as a GDB server debug probe, and as such it includes scripting support. This scripting can be very useful in some cases where the MCU cannot be accessed by a normal debug session. This happens for example if students are not pay attention what binary they flash to which device, causing an MCU to potentially get ‘bricked’.
In many of my embedded projects I need persistent data or storage for settings. If using an SD card, then FatFS is usually my choice for the file system. But if using an external FLASH memory device, then my preferred choice is usually LittleFS: it is a little fail-safe filesystem, designed for micro-controllers, which I’m using with external flash memory devices.
In the case where there is enough MCU flash, or if there is no external FLASH device available in a design, it can use the MCU internal FLASH as storage storage too. This is the topic of this article:
Embedded hardware comes with limitations, and one if it is the given number of hardware breakpoints. Depending on your MCU, 4 or only 2 hardware breakpoints are available, making debugging and stepping in read-only memory (FLASH) a challenge.
Did you know that one can have ‘unlimited’ number of breakpoints in FLASH, with the help of GDB? This is very useful for extended debugging, or if you want to use breakpoints for testing?
Continue readingSometimes it makes sense to write everything in assembly, even these days. For example if using a tiny microcontroller. Or just if one just don’t need all the productivity of the C/C++ tools. And it is a good educational experience: getting hands-on on the lower levels.
MCU on Eclipse 