In “Tutorial: MCUXpresso SDK with Linux, Part 1: Installation and Build with Maked” I used cmake and make to build the SDK application. In this part I’m going to use the command line gdb to debug the application on the board.
My LoRaWAN gateway (“Contributing an IoT LoRaWAN Raspberry Pi RAK831 Gateway to The Things Network” is running and working great now for more than a month and it already has transmitted more than 30k messages:
This creates a lot of log entries on the micro SD card of the Raspberry Pi. To avoid writing too many times log data, I have installed Log2Ram.
In the IoT world, it is all about security, connectivity and low power. LoRaWAN with the Things Network is able to connect devices over several kilometers, and I’m running my gateway for it already (see “Contributing an IoT LoRaWAN Raspberry Pi RAK831 Gateway to The Things Network“). This tutorial is about building a BLE+LoRaWAN+GPS sensor node with GNU tools and Eclipse:
In “Debugging the RV32M1-VEGA RISC-V with Eclipse and MCUXpresso IDE” I described how to build and debug applications for the VEGA RISC-V board. In this article I describe how to enable FreeRTOS for RISC-V, based on the latest FreeRTOS V10.2.0 release.
LoRa and LoRaWAN is getting the de-facto wireless IoT network in my area. No surprise that traditional telecom providers like Swisscom trying to monetize the ‘Internet of Things’ area. Luckily there is an open and free alternative: https://www.thethingsnetwork.org/. Volunteers, enthusiasts and members in the different TTN communities build gateways and offer free LoRaWAN network access. I wanted to contribute to that grassroots movement with building my gateway, providing LoRaWAN access to my neighborhood.
Most of the time software needs some way to configure things: depending on the settings, the software will do different things. For example the software running on the microcontroller on top of the Raspberry might have the OLED LCD available or not:
How can I deal with this in my application code? Continue reading
In the age of high-resolution graphical LCDs using a character display might look like a bit anachronistic. But these displays provide a lot of value for me as they are robust, available in different shapes and number of lines. And such a character display can be a better solution for an industrial application.
Most host or desktop systems (say Linux, Mac or Windows) have a normal use case where you start the operating system say in the morning and shut it down in the evening, and then you leave the machine. Embedded Systems are different: they are not attended, and they are supposed to run ‘forever’. Not every embedded system needs to run an OS (or in that world: Real-Time Operating System or RTOS), but the same applies here: after the RTOS is started, it is not intended that it will shutdown and restart. To the extend that you won’t they support the ‘shutdown’ and ‘restart’ functionality at all. In case of gathering coverage information this would be really useful:
In the case of FreeRTOS: what if I really need to shutdown the RTOS and restart it again, as by default this is not supported. This is what this article is about …
Modern microcontroller come with plenty of internal FLASH memory. On the other side, many high performance MCUs as the NXP i.MX RT are ‘flashless’, because the silicon process for high performance cores is not matching the FLASH memory technology, so they are using external serial SPI or Quad-SPI (QSPI) memory instead.
Why not using an external SPI FLASH for a ‘normal’ microcontroller too?
I’m using the VL6180X ToF (Time-of-Flight) sensors successfully in different projects. The VL6180X is great, but only can measure distances up to 20 cm and in ‘extended mode’ up to 60 cm. For a project I need to go beyond that, so the logical choice is the VL53L0X which measures between 30 cm and 100 cm or up to 200 cm. For this project I’m using the VL53L0X breakout board from Adafruit, but similar products are available e.g. from Pololu.
You might wonder what ‘Zork‘ is? Zork is one of the first and earlist fictive computer games, written around 1977 and 1979, written in MDL on a DEC PDP-10 by members of the MIT Dynamic Modelling group (see https://en.wikipedia.org/wiki/Zork). I believe the first time I have played Zork was around 1984 on a Commodore 64.
With Eclipse as IDE it is very easy to debug an application on a board. Still sometimes it is useful to get one level down and control the GDB server directly.
There are things which are game changer in the world of software development: one such event was when I started using a VCS (Version Control System): it changed for me how I keep and store my projects and settings. It even changed the way how I deal with non-software related items like documents or other valuable things: I started storing them in to a VCS too.
Unit testing is a common practice for host development. But for embedded development this still seems mostly a ‘blank’ area. Mostly because embedded engineers are not used to unit testing, or because the usual framework for unit testing requires too many resources on an embedded target?
What I have used is the μCUnit framework which is a small and easy to use framework, targeting small microcontroller applications.
Open Source software has been around for decades. But open source on hardware especially microcontroller is not much a reality these days. But there is something which might change this: RISC-V is a free and open RISC instruction set architecture and for me it has the potential to replace some of the proprietary architectures currently used. RISC-V is not new, but it gets more and more traction in Academia (no surprise).
I wanted to play with RISC-V for over a year, but finally a week ago I did one of these “hey, let’s buy that board” thing again. Sometimes these boards get on a pile to wait a few weeks or longer to get used, but that one I had to try out immediately :-).
Most embedded projects need an user input device. For the NXP i.MX RT1050-EVK board I have recently added a 480×272 full color touch LCD (see “Adding a Rocktech Capacitive Touch LCD to the NXP i.MX RT1052 EVK“). I have looked at different commercially available GUI libraries, but none of them really were matching my expectations: either very expensive or closed source, or an overkill for small LCDs and projects. But then I have found LittlevGL: free-of-charge, open source, easy to use, well documented and has everything I need. And it really looks gorgeous 🙂
In this short article I show you how to enable one of the hidden gems in Eclipse: how to get a description of the library function used in the code
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: