With semihosting I can use standard I/O function like printf() and I can read and write data on the host through the debug connection. If used with care, this is a great feature especially for unit testing.
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.
It 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 readingOne essential part of embedded development is the ability to debug the target application. The good thing with the Raspberry Pi Pico RP2040 Eco-system is: One can use another RP2040 Pico board as a debug probe to debug other ARM Cortex-M devices.
But instead using a Raspberry Pi Pico board with some wires, why not building a dedicated board? The result is a small, versatile and open source debugging probe which virtually can debug any ARM Cortex-M device as a standard ARM CMSIS-DAP probe:
I love the WS2812B (aka SK6812) addressable LEDs: they are inexpensive and available in different packages. I have used them in different projects, including the MetaClockClock one. I used the NXP Kinetis for these projects, but because they are not available any more, for a new project we had to choose a new microcontroller, with the Raspberry Pi Pico RP2040 as the winner.
When something goes wrong in an embedded system, a watchdog timer is the last line of defense against a blocked or malfunctioning system. A watchdog is a special timer which needs to be ‘kicked’ in a special way, otherwise the timer will run out and reset the system.
For example, a watchdog is an important safety feature in the E-Vehicle charging controller with Raspberry Pi Pico-W RP2040:
The Raspberry Pi Pico RP2040 is a very versatile microcontroller. It is not the least expensive or the most powerful microcontroller, but it is one which is available and has an excellent software and tool ecosystem.
This article shows how to use the Raspberry Pi Pico-W with BLE and optional WiFi, running with FreeRTOS.
I’m in the final stage of finishing a electrical vehicle (EV) charger controller, which optimizes battery loading using the available PV system: use as much as possible the solar energy and not the grid.
While the controller talks with an Modbus (RS-485) interface to the vehicle charger itself (see Controlling an EV Charger with Modbus RTU), it uses MQTT over WiFi to get information about the available solar energy from HomeAssistant and the Powerwall.
Continue readingThe year 2022 is coming to an end, and I have spent some time today on a little side project. It is about making an Electrical Vehicle (EV) wallbox charger accessible over Modbus RTU. It is not finished yet, and I plan to publish more articles on it, but I can share that I’m able to access and control the Heidelberg EV charger with a Raspberry Pi Pico W (Dual Core Cortex M0+), NXP K22FN512 (Cortex M4F) and LPC845 (Single Core Cortex M0+):
I’m pleased to announce a new release of the McuOnEclipse Processor Expert components, available on SourceForge.
MCU on Eclipse 