Preprocessor Listing for GNU gcc with GNU ARM Eclipse Plugins

In case there are problems with the C/C++ preprocessor, it is useful to generate the compiler preprocessor listing. Here is how to create a preprocessor listing with GNU gcc compiler and the GNU ARM Eclipse plugins in Eclipse:

Preprocessor Listing in Eclipse

Preprocessor Listing in Eclipse

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McuOnEclipse Components: 22-Nov-2015 Release

A lot of good things happened in the last three weeks, so here is a new updated McuOnEclipse component release, with the following main improvements:

  1. Updated Segger RTT component
  2. New Segger SystemView component
  3. FreeRTOS ‘tasklist’ shell command
  4. FreeRTOS with support for Segger SystemView

SystemViewer

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Data Logger with tinyK20 Board

First off: The tinyK20 project is progressing fine and is now on Hackaday.io :-).

For a research project we would like to use the tinyK20 to log gyro sensor data. For this I have created a quick-n-dirty project to explore how feasible it is. The tinyK20 has all the pins on the outside of the board, so I’m able to put it on a bread board:

tinyK20 on Breadboard

tinyK20 on Breadboard

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GNU gcc printf() and BuiltIn Optimizations

Readers of my blog know: I’m not a fan of printf(), and I think for many good reasons. Still printf() is widely used, and the GNU gcc tries to optimize things. This is observed with a simple example: If I’m writing

printf("a");

Then the code produced (ARM Cortex-M0+ with GNU ARM Embedded 4.9 2015q2 gives:

movs r0, #97    ; 0x61
bl 0xa98

Instead of calling printf(), it is calling putchar()! Why is that?

PutChar instead of Printf

PutChar instead of Printf

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Segger SystemView: Realtime Analysis and Visualization for FreeRTOS

One of the most important aspects for developing complex realtime applications is get insights into what is going on the target. Segger just has released a free tool which gives an incredible useful insight view and visualization:

Segger System View for FreeRTOS

Segger System View for FreeRTOS

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