issue 69 - Embedded systems newsletter

Embedded systems #69

Hardware

Hardware Teardown: the Withings GO activity tracker
In this post, November Five is treating Withings GO small activity tracker less kindly: they open up the casing, look at all of the main components and what they do, and try to recreate the BOM (Bill Of Material) and COGS (Cost of Goods Sold) to determine the actual cost of this tracker retailing for €69,99.

The world’s easiest TRNG to get right
One day, all hardware designers are in the struggle to design a good random number generator source in their design. This repository may save you plenty of time if this day is coming for you

How accurate is microstepping?
Stepper motors divide a full rotation into hundreds of discrete steps, which makes them ideal to precisely control movements, be it in cars, robots, 3D printers or CNC machines. Most stepper motors you’ll encounter in DIY projects, 3D printers, and small CNC machines are bi-polar, 2-phase hybrid stepper motors, either with 200 or — in the high-res variant — with 400 steps per revolution. This results in a step angle of 1.8 °, respectively 0.9 °.

Computational RAM
C-RAM is random access memory with processors incorporated. The goal of Computational RAM is to build cheap massively-parallel computer

Software

A fast, memory efficient hash map for C++
Actually I don’t know any implementation that use less memory. It deserves a look. If you know any other implementation as good as this one, please, share it with me

SGL - Simple Graphical Library
SGL is a low-level agnostic library that provides basic graphical functionalities. The separation of concerns is very clear. It may be a good starting point to whom is doing a graphic visualisation

Using the C Preprocessor to Perform Compile-time Computations
Before reading this article I would say that it is probably impossible to compute a logarithm at compile time. You will be as surprised than I was

Demystifying Git internals

Misc

Handwritten coding sheets for Burroughs 205 Algol (1960)

My resume in an Operating system
“This is one of the most useless idea I’ve ever had — making an operating system that only shows my resume.”

Adam Taylor’s MicroZed Chronicles: OpenCV EV Object Tracking