A simple digital generator
In this project I developped a simple yet powerful digital (TTL) generator. Built around an Arduino Nano, the generator fits in a small portable 3d-printed package but it features single step or square-formed periodic signals, manual control of the delivering time or a preset number of periods, and control via the serial connection as well as a LCD with a selectable menu. Last but not least: there is a switch to choose between 3.3V and 5V.
Direct control of the XL 320 servo with a Raspberry
This post introduces a custom C++ library to control the popular Dynamixel XL 320 servo directly with a Raspberry Pi 4, without the need for an additional controller/shield like the OpenCM board. You'll just need a level shifter to drive the motor and LED and an additional logic gates IC in case you want to read the servo's output, but these are cheap and popular electronic components. The Rasberry configuration and wiring are included, with everything you need to have a working setup rapidly.
A complete 8-bit cheatsheet
Here is a one-page cheatsheet with all decimal, hexadecimal and binary codes for all digits from 0 to 255. In addition you also have the corresponding characters (i.e. the standard ASCII characters for the first 128 digits) which is often useful to have on hand. To print and pin on your wall if you are often programming devices at a low-level!
A stackable manifold for micro-valves
There can be numerous good reasons to use a computer-controlled microvalve: with low dead volumes and fast switching times they can be used for millifluidics, microfluidics or automation. Two common pitfalls are the driving electronics and the mechanical connection of the valve with the circuit. In this post I detail how to build a stackable manifold with Luer connectors for microvalves driven by a digital signal. Download all conception files for easy replication!
