I have carefully implemented my firmware. It works perfectly for hours, days, months, maybe for years. I there would not be a problem: the firmware crashes sporadically :-(. Yes, I’m using watchdogs to recover, but hey: it is a serious problem. And because it happens only under rare and special conditions, it is hard to track it down or to debug it.
Accessing shared data from the main application and from an interrupt
The thing is: these nightmares exist, and they are real and nasty. I’m pushing my students hard on this topic: It is about how to protect critical sections. And what could go wrong. And here is just yet another example: how it can go badly wrong if you are not careful. And it took me a while too to realize where the problem is. It was not a fun ride….
January 25th 2014. It was a cold night, with little snowfall overnight. A beautiful morning, blue sky with a wonderful sun light, slowly melting away the snow in the lower areas. Parts of Lake Lowerz are still frozen. The green … Continue reading →
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 🙂
‘Inversion‘ is a meteorology phenomena in my area in Switzerland: typically the air gets colder the higher you get up in the mountains. But under special conditions during Fall/Winter time, it is possible that cold air is on the ground, … Continue reading →
Processor Expert Driver Suite 10.3 Project with GNU ARM Eclipse Build Tools
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.
The Freescale Tower boards are very versatile, and there are many different boards you can combine like lego bricks. When I tinker with my own hardware or need to try out something, then I use a special prototype board: the TWR-PROTO.
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)?