One of my embedded projects is to measure the running time in a sports event (see “Sports Timing System in a Lunch Box“). The recorded time is stored in an EEPROM plus sent over USB or wireless connection to the host. It would be great if I could print out the time and ranking directly, so if there is no PC, the system can be small and tiny. So here is my next project and tutorial: Printing with the Freedom board!
Using Processor Expert is an awesome tool: it generates source code for me, and I can can ‘dynamically’ tune my projects to my needs. Still, sometimes it is better or desirable to have a ‘normal’ or ‘static’ project. This is very well possible with Processor Expert (see “Sneaking from Processor Expert” or “Disable my Code Generation“): I can generate the code one time, and then use it without Processor Expert.
To make this even easier, I have added an option to the FreeRTOS Processor Expert component to generate ‘static’ code I can copy-paste to projects and tool chains which are either not supported by Processor Expert, or just for ‘static’ projects.
Naturally, I have several project ideas lingering around. No time to make them all (for now). One of it is interfacing the Raspberry Pi camera with a microcontroller. To store the images, I need plenty of RAM on the device, and so far the Kinetis microcontroller did not have that. Finally, Freescale announced the K64F120 a few months back, and my ordered TWR-K64F120M board arrived on my desk, waiting to be used: Finally I get an ARM Cortex-M4F with 1 MByte of FLASH and 256 KByte of RAM :-).
On Monday the new semester starts, and yet again: we will do a Sumo thing :-). They can choose which tool chain they would like to use to develop their application for the ARM Cortex-M0+ used from Freescale. One option is to create a ‘Do-It-Yourself’ toolchain. Since the start of the series, things have evolved: there is a new GNU ARM tool chain available, Segger has updated their drivers, and most important the GNU ARM Eclipse plugin has been greatly extended to support Freescale parts and Processor Expert. So instead to read through all the previous tutorials, this one is about putting together a free tool chain less than 10 minutes (not counting the time to download around 500 MByte).
University research projects can be a lot fun, and are very challenging the same time. The good thing is that there is always someting new to learn :-).
This week-end I was working on my Internet of Things (IoT) project, based on a Freescale KL15Z and a nRF24L01+ transceiver. In essence it is a wireless data logger. For this, I only can afford a few micro amps consumed by the whole board over an extended period of time. I mean 21 micro amps for running a whole board with sensor, EEPROM, wireless transceiver, operating system and an ARM Cortex-M0+ ready to crunch numbers at 20 MHz
I have created and published on GitHub a new component ‘CriticalSection’:
This component is a wrapper between my components and the problematic current implementation in Processor Expert (see
ExitCritical(): Why Things are Failing Badly). It uses a flexible approach and uses macros to either use my modified version of
ExitCritical(), or simply defaults to the original implementation.
This is Part 3 of an ongoing tutorial to use the Arduino Ethernet Shield R3 with a Freescale FRDM-KL25Z board (or any other board you like).
In Part 1 I worked on the SD card, in Part 2 I have added basic network connection. Now time to run a web server with my FRDM-KL25Z :-). With this, I can get access to my board through the network, and the board will host a web page where I can do pretty much everything: showing status, or adding functions to turn on things like an LED
There has been many new releases these days: Freescale released Processor Expert Driver Suite 10.3, and Liviu Ionescu released new GNU ARM Eclipse Plugins with new and updated documentation. So time for me to show how this all comes together
It is now easier than ever before to use the GNU ARM Eclipse plugins and Processor Expert. There are still some manual steps, and this post is about all the details to get it working as smooth as possible.
I’m maintaining and hosting now more than 100 different Processor Expert components on GitHub. Instead to deal with CDE (Component Development Environment, that’s the SDK to create your own components), most users simply download and install the PEupd files. If you deal with normal source files, and if spot something you want (or need to change), then you can easily do this. But what if you want or need to change something in that code which comes with the PEupd file(s)?
I have I project which I want to debug on multiple boards the same time. So how can I download and debug the same application to multiple boards/processors, and debug them all the same time from within the same workspace and Eclipse IDE?
This is a typical scenario I have with my RNet stack: the same application runs on multiple boards, and I want to debug all the boards with the same project with the same Eclipse. For example to wireless sensor nodes with the RNet nRF24L01+ stack as in the picture below:
Tired by the tool chains provided by your silicon vendor? Do you want to use a free and open tool chain? Then you probably followed by “DIY Free Toolchain” series already. In “DIY Free Toolchain for Kinetis: Part 2 – Eclipse IDE” I used the standard GNU Eclipse plugins. As mentioned in above post, there is an even better and more powerful plugin available: the GNU ARM Eclipse plug-ins. There is a dedicated blog site (http://gnuarmeclipse.livius.net/blog/) which provides excellent documentation and direct access to new and frequent releases. And these days there is a true a Christmas gift for every Eclipse lover: the version 1.1.7 with the addition of J-Link debugger plugin :-).
This post is not about variables in my application code (which I debug). It is about using Variables in Eclipse for building projects. Eclipse variables allow me to make my projects ‘position independent’ whenever I cannot use a path relative to my projects or workspace.
Which variables are used where in Eclipse might be sometimes not very clear. Depending in which context variables are used, not everything might be available. This link for example gives a list of variables which can be used to invoke an external tool.
Eclipse comes with many built-in variables, especially for the build system. If I want to see what variables are already defined, I can show them in the project properties, under C/C++ Build > Build Variables with enabled option ‘Show system variables’:
I have one rule I try to follow every day: my code shall be warning free. Writing software for multiple compilers gets challenging with this rule, but it avoids the ‘not seeing the forest because of the trees’ problem. This rule extends to writing Processor Expert components with CDE (Component Development Environment). What I have missed (and not used) is a useful option to enable debug output: