Tutorial: Using GNU Profiling (gprof) with ARM Cortex-M


I have published a Sneak Preview how GNU gprof profiling looks for an embedded target ARM Cortex-M in an earlier post:

Freescale Kinetis Microcontroller Application Profiling

Freescale Kinetis Microcontroller Application Profiling

This tutorial explains how to profile an embedded application (no RTOS needed) on ARM Cortex-M devices with GNU gprof. Additionally I explain the inner workings to generate the data necessary for gprof.

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Debugging STM32F103RB NUCLEO Board with Segger J-Link


The STMicroelectronics STM32F103 (ARM Cortex-M3) Nucleo boards include the on-board ST-Link v2 circuit which allows to debug the board. This circuit is similar to the OpenSDA circuit found on Freescale boards. Unlike the Freescale OpenSDA, the ST-Link is only the ST-Link: it is not possible to load a P&E Multilink or Segger J-Link or firmware on it. Luckily, the ST-Link has a SWD connector, but this connector is a non-standard one. So how can I debug that board with an Eclipse based environment with GNU ARM Eclipse plugins and a Segger J-Link?

Connected J-Link with Nucleo Board

Connected J-Link with Nucleo Board

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Using the Freescale Freedom (FRDM-KL43Z) to Debug other Boards


In “Unboxing the Freescale FRDM-KL43Z Board” I was using the FRDM-KL43Z board the first time. The FRDM-KL43Z board has an on-board debug interface (Kinetis K20, OpenSDA). In this post I show how to use the FRDM-KL43Z board to debug another ARM board.

FRDM-KL43Z Board debugging custom (tinyK20) Board

FRDM-KL43Z Board debugging custom (tinyK20) Board

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Overview: From Snippets to Code Generation


To build an application for a modern microcontroller today is not a simple thing. Well, it depends what ‘simple’ means. But compared to the ‘old days of 8bit micro controllers’ (which are still in use!) developing for a complex 32bit device is definitely a different thing. Not only the complexity has changed, but as well the breath of tools and helpers. In my view, the only constant is ‘change’, and I have changed the way how to develop several times in my career. In this post I present several different techniques I’m using in my development.

Processor Expert CPU View

Processor Expert CPU View

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Sneak Preview: Profiling Bare Metal Microcontroller Applications with GNU gprof


I’m working on a conference paper and presentation, and tonight I had a break-through :-). So how cool is this: Profiling with GNU gprof a bare-metal embedded Cortex-M application (Freescale Kinetis K64F running the Freescale Kinetis SDK) in Eclipse:

Freescale Kinetis Microcontroller Application Profiling

Freescale Kinetis Microcontroller Application Profiling

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Revert an Eclipse Update Installation


I’ve been running into an issue with an Eclipse plugin update: I updated a plugin, and then broke a critical functionality. What I usually do is to uinstall the plugin (see “Uninstalling Eclipse Plugins“), and then install it again. However, in this case the uninstall ended with an error too :-(.

Uninstall failed

Uninstall failed

What now? How can I revert that plugin installation/update?

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Tutorial: Adafruit WS2812B NeoPixels with the Freescale FRDM-K64F Board – Part 5: DMA


This is Part 5 of a Mini Series. In Part 4, I described how to set up the FTM (Kinetis Flex Timer Module) to generate the required waveforms used for DMA operations (see “Tutorial: Adafruit WS2812B NeoPixels with the Freescale FRDM-K64F Board – Part 4: Timer“). In this post I describe how to use to trigger DMA (Direct To Memory) events. The goal is to drive Adafruit’s NeoPixel (WS2812B) with the Freescale FRDM-K64F board:

FRDM-K64F with Adafruit NeoPixel

FRDM-K64F with Adafruit NeoPixel

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