Analyzing the Linker Map file with a little help from the ELF and the DWARF

Govind Mukundan December 27, 20156 comments

When you're writing firmware, there always comes a time when you need to check the resources consumed by your efforts - perhaps because you're running out of RAM or Flash or you want to optimize something. The map file generated by your linker is a useful tool to aid in the resource analysis. I wanted to filter and sort the data generated in an interactive way so I wrote a C# WinForms application that reads the data from the map and presents it in a list view (using the awesome


Short Circuit Execution vs. Unit Testing

Stephen Friederichs July 7, 20141 comment

The key to effective communication is to say what you mean and avoid ambiguity.  Words and phrases with multiple meanings can confuse your audience and hinder communication. That’s why so many programmers prefer writing code to writing specifications: written human language introduces ambiguity and subsequently, confusion. Code only has one interpretation, period. This doesn’t, however, ensure that the right message is getting through. Code can, indeed, only do one thing,...


Unit Tests for Embedded Code

Stephen Friederichs March 6, 201411 comments

I originate from an electrical engineering background and my first industry experience was in a large, staid defense contractor. Both of these experiences contributed to a significant lack of knowledge with regards to software development best practices. Electrical engineers often have a backwards view of software in general; large defense contractors have similar views of software and couple it with a general disdain for any sort of automation or ‘immature’ practices.  While there...


Delayed printf for real-time logging

Yossi Kreinin October 25, 20133 comments

You often debug by adding a few printfs and looking at the logs. In some real-time/low-level contexts though, you don't have time for text formatting.

You don't want prints to affect timing too much, because then timing-related bugs you're chasing might disappear. And you certainly don't want the system to stop functioning altogether because prints cause it to miss real-time deadlines.

A common alternative to prints is more "raw" logging - an event buffer, where event is a union keeping...


Debugging with Heartbeat LEDs

Stephen Friederichs April 2, 2013

In this article I’ll discuss one of the most basic debugging tools in an embedded system: the heartbeat LED.  Picture this: you’re developing your first program for a new microcontroller. You’ve written the code, configured the programmer, downloaded the HEX file and now... what Your program is running - isn’t it?

Truth is that it’s hard to tell with most embedded software.  Compared to desktop or even server applications embedded software tend not to have very many...


Delayed printf for real-time logging

Yossi Kreinin October 25, 20133 comments

You often debug by adding a few printfs and looking at the logs. In some real-time/low-level contexts though, you don't have time for text formatting.

You don't want prints to affect timing too much, because then timing-related bugs you're chasing might disappear. And you certainly don't want the system to stop functioning altogether because prints cause it to miss real-time deadlines.

A common alternative to prints is more "raw" logging - an event buffer, where event is a union keeping...


Unit Tests for Embedded Code

Stephen Friederichs March 6, 201411 comments

I originate from an electrical engineering background and my first industry experience was in a large, staid defense contractor. Both of these experiences contributed to a significant lack of knowledge with regards to software development best practices. Electrical engineers often have a backwards view of software in general; large defense contractors have similar views of software and couple it with a general disdain for any sort of automation or ‘immature’ practices.  While there...


Analyzing the Linker Map file with a little help from the ELF and the DWARF

Govind Mukundan December 27, 20156 comments

When you're writing firmware, there always comes a time when you need to check the resources consumed by your efforts - perhaps because you're running out of RAM or Flash or you want to optimize something. The map file generated by your linker is a useful tool to aid in the resource analysis. I wanted to filter and sort the data generated in an interactive way so I wrote a C# WinForms application that reads the data from the map and presents it in a list view (using the awesome


Debugging with Heartbeat LEDs

Stephen Friederichs April 2, 2013

In this article I’ll discuss one of the most basic debugging tools in an embedded system: the heartbeat LED.  Picture this: you’re developing your first program for a new microcontroller. You’ve written the code, configured the programmer, downloaded the HEX file and now... what Your program is running - isn’t it?

Truth is that it’s hard to tell with most embedded software.  Compared to desktop or even server applications embedded software tend not to have very many...


Short Circuit Execution vs. Unit Testing

Stephen Friederichs July 7, 20141 comment

The key to effective communication is to say what you mean and avoid ambiguity.  Words and phrases with multiple meanings can confuse your audience and hinder communication. That’s why so many programmers prefer writing code to writing specifications: written human language introduces ambiguity and subsequently, confusion. Code only has one interpretation, period. This doesn’t, however, ensure that the right message is getting through. Code can, indeed, only do one thing,...