One of the great things with the FreeRTOS operating system is that it comes with free performance analysis: It shows me how much time is spent in each task. Best of all: it shows it in a graphical way inside Eclipse too:
FreeRTOS Runtime Information in Eclipse
To solve the real hard problem of Embedded Systems development, I usually need all the data I can get from the target. The Percepio Tracealizer is such a tool which can stream application and FreeRTOS trace from the target over a Segger J-Link connection using the Segger RTT protocol. I’m using that combination a lot.
Streaming trace data that way does not need a dedicated hardware like ETM Trace. Using RTT is usually not much intrusive and affects the performance of the target in the 1-2% range (of course depending on the amount of data).
But what worried me for several weeks is that after moving to FreeRTOS V10.0.0 and the same time updating the Segger libraries, the target performance was heavily affected:
RTT streaming affects target performance?
Right before the start of the new semester, the new tinyK22 boards (see “First tinyK22 Board with NXP K22FN512 ARM Cortex-M4F“) arrived, and they are looking great 🙂
tinyK22 Board
Three years ago I published “Debugging Failure: Check List and Hints” and unfortunately this article is one of the most popular ones: obviously debugging problems are very common. Debugging with GDB works usually fine, but if things are failing, then it can be hard to find the cause for it. Recently I have been asked to check some failures, so here are two more hints about what could go wrong…
Error while launching command: arm-none-eabi-gdb –version
Binary files are just a binary blob without debug information. Most debug tools and flashers are able to deal (raw) binary (see “S-Record, Intel Hex and Binary Files“). But GDB or the P&E GDB server really needs a ELF/Dwarf file which usually has all the debug information in it. This is a problem if all what I have is a binary file.
This post is about transforming a raw binary (.bin) file into an ELF/Dwarf file with adding a header to it:
Added Elf Header to Raw Binary File
I’m making great progress with the firmware for the new Mini Sumo Robot (see “New Concept for 2018 Mini Sumo Roboter“). The goal is a versatile and low-cost Mini Sumo robot, and the robot comes with the feature of magnetic position encoders. In a previous article I have explained how to mold custom tires for robots (see “Making Perfect Sticky DIY Sumo Robot Tires“), this article is about how to make DIY Magnetic disk encoders.
3D Printed Magnetic Encoders Disks
With the hiking trails covered with as much as 50-60 cm snow, the natural way to hike the trails is using snowshoes. Two days ago an extra 10-15 cm snow arrived, and the trails are just amazing. Here are a few impressions from the snowshoe hike today:
Starting the New Year in the mountains, with cold snow covering everything. Beautiful view to the peaks, illuminated by last sun rays of New Year’s Day.
Sunset in the mountains (Click to enlarge)
Happy New Year!
The Teensy boards are great, but as they are they are not really useful for real development, as they lack proper SWD debugging. In “Modifying the Teensy 3.5 and 3.6 for ARM SWD Debugging” I have found a way to get SWD debugging working, at that time with Kinetis Design Studio and the Segger J-Link. This article is about how debug the Teensy with free MCUXpresso IDE and the $20 NXP LPC-Link2 debug probe:
Teensy 3.6 with NXP LPC-Link2
Sumo robot challenges are fun. One important aspect of every Sumo robot are the tires: if they are sticky enough, the robot can push out the opponent. In this article I compare different available robot hubs and tires, and how to make DIY hubs and tires.
Selection of Sumo Robot Wheels and Tires
MCU on Eclipse 