Debugging the LPC804 on the MCU-Link Pro with an external Debug Probe

The NXP MCU-Link Pro debug probe includes a LPC804 as an additional microcontroller on the board, including its debug header.

MCU-Link Pro Debug Probe Board

The question is: how to debug the on-board extra LPC804 microcontroller with an external debug probe?

Continue reading

Recovering bricked LPC55Sxx EVK Boards

While developing applications, it can happen that things go wrong. And in my case I ended up with two LPC55Sxx EVK boards on my desk, which seemed not to be usable any more. The issue: the boards were not accessible with the debug probe, because right after main they muxed the pins in a wrong way :-(.

bricked board with set of debut probes

The standard GDB debug connections (both on-board and off-board) were not able to regain access of the board, because the MCU was running into the fault condition pretty much right out of reset.

Luckily, after a lot of trial-and-error, I have found a way to recover them.

Continue reading

Debugging with Dynamic Printf Breakpoints

I’m not a big fan of using printf() in embedded applications, but I have to admit that in some cases it is very useful. One problem in debugging embedded systems debugging is getting values or information off the target: because of the limited resources this can be very challenging.

So why not doing this with the debugger in an automated way? And here dynamic printf breakpoints can help: it adds printf()-style output on-the-fly to your program without the need to recompile or restart your program, without the need to run printf() on the target:

Using Dynamic Printf Breakpoint
Continue reading

MCUXpresso IDE 11.5.0

I’m now in the middle of the university fall semester exam season with writing exams and grading student work, and the same time the new semester courses need to be prepared. With the global silicon and board shortage, this will be again a challenge to equip all the labs with the needed infrastructure. The good thing is that there is no shortage on software and tools side of the infrastructure: NXP released last week their new flagship Eclipse based IDE: the MCUXpresso IDE 11.5.0. Time to check it out for the upcoming lectures and classes….

NXP MCUXpresso IDE Version 11.5.0

Spoiler Alert: It has a new view for FreeRTOS lovers, plus new features for energy/power measurements!

Continue reading

Visual Studio Code for C/C++ with ARM Cortex-M: Part 10 – Assembly Stepping

The Microsoft Visual Studio Code is a great IDE, but does not (yet?) implement features for true embedded usage. Or things are there to some level, but hard to use. One of these things is how to step in the assembly code. This article shows how to do this.

Continue reading

New “MCU-Link Pro”: Debug Probe with Energy Measurement

After the release of the NXP MCU-Link debug probe, there have been hints in the Eclipse based MCUXpresso IDE that there must be another one coming. And indeed: another and more powerful debug probe is now available: the MCU-Link Pro. It is not only a debug probe but a power/energy measurement tool too, including an extra LPC804 mikrocontroller which can be used for all kind of things, like automation or scripting.

NXP MCU-Link Pro
Continue reading

Visual Studio Code for C/C++ with ARM Cortex-M: Part 9 – RTT

For me the Cortex-Debug Visual Studio extension by marus25 is the standard way to use VSC for embedded development. Another ‘standard’ piece I’m using in many of my projects is the SEGGER RTT.

SEGGER RTT Output with Visual Studio Code
Continue reading

Tutorial: GNU gcov Coverage with the NXP i.MX RT1064

This tutorial shows how to use and collect coverage data using the GNU gcov tool. As board and hardaware I’m using the NXP i.MX RT1064 EVK:

MIMXRT1064-EVK running ThreadX

While this tutorial uses this specific board, things are pretty generic and should be applicable for any other board or MCU.

Continue reading

Visual Studio Code for C/C++ with ARM Cortex-M: Part 8 – xPack C/C++ Managed Build Tools

This is a new article in my series about using Microsoft Visual Studio Code: After installation, project setup, building, debugging, setting up a kit, IntelliSense and FreeRTOS. This one is about setting up and using the xPack Extension to build cross-platform-multi-tool project with a project manager.

Continue reading

Position-Independent Code with GCC for ARM Cortex-M

Welcome to ‘Alice in Wonderland‘! For a university research project using an ARM Cortex-M33 we are evaluating position-independent code as way to load applications or part of it with a bootloader. It sounds simple: just add -fPIC to the compiler settings and you are done.

Unfortunately, it is not that simple. That option opened up a ‘rabbit hole’ with lots of wonderful, powerful and strange things. Something you might not have been aware of what could be possible with the tools you have at hand today. Leading to the central question: how is position-independent code going to work with an embedded application on an ARM Cortex-M?

Let’s find out! Let’s start a journey through the wonderland…

Continue reading