Raspberry Pi is a small factor fully-featured computer. It can be used for multiple purposes such as a controller.
In most of applications it is necessary to use some kind of communication interface. Raspberry Pi delivers, among others, UART, SPI and I2c. However, UART (serial port) is most commonly used if you just want to send some data between RPi and other devices. While using SPI or I2c in i.e. python script is rather straightforward, using serial port, or making it to work, isn’t so easy as it might seem.
Some time ago I have written a few real-time Linux drivers for Xenomai and complementary OROCOS components. But first thing first! What the heck is Xenomai and OROCOS? To keep it as short as possible; Xenomai is an open-source project which aim is to bring real-time API to Linux based system. It is an extension to the Linux kernel which makes it a hard real-time operating system. On the other hand, OROCOS is a robotic framework that brings a vast number of libraries and a toolchain to create components. What is more, Xenomai and OROCOS do play along which means you can facilitate features of both i.e. to create a hard real-time components.
If you are interested you can find the code for each driver and for each OROCOS component on my GitHub repository. Feel free to fork!
Below are direct links to the repositories:
Some time ago I decided to give KiCAD a shoot, actually it was a second attempt. For a long time I have been using Eagle CadSoft but now the disadvantages tip the scale. Also now, KiCAD has a crazy new feature which is called interactive routing. However, KiCAD is not quite straightforward and it requires some getting use to. One thing that struck me was the necessity of Internet connection. When you want to connect components with appropriate footprints using CvPcb it scans the library paths. And it is here where the problem starts…
Recently I have written a short post about the HAL library created by STM32. The HAL is gaining popularity among hobbyists and is more and more frequently used. However, when you would like to use it for something else than just basic stuff like generating PWM on digital output you have to write it by yourself. Not so long ago I had to use SD card in one of my projects. It turned out that there is no driver for FatFS based on HAL – at least there was not. I decided to write the driver and here you can read about it…
There is an unending dispute about which library should you use when writing an application for STM32 microcontroller. Actually, there are at least three choices which you should consider. In this post I will highlight the advantages and disadvantages of each approach which can be considered when writing software for ST microcontrollers.
Wireless transmission is getting more and more popular. I will try to show you how does it work using coupled receiver and transmitter which are both working on the same frequency (433MHz).
There are many operating systems: Linux, Windows, iOS,… But there are a few which can work in real time like Linux Xenomai. However, there are very little which can fit a microcontroller. One of them is a FreeRTOS. There are some variations of the FreeRTOS which can handle different conditions and requirements.
This blog post is not about such operating system, however…
It was quite a long time since I have written something about my QuadroCopter. Well the time has come. I have prepared a shot movie to which I invite you to watch.
Read more for some technicalities about the UAV.
Some time ago I have written about my RepRap clogging problem. When I have switched to PLA I had some problems with extruder jams. It was solved by switching to different extruder and adding a fan for active cooling.
Some time ago I have decided to switch from the ABS filament to the PLA filament. This is how it starts 🙂 …
The purpose of this article is to introduce you to one of the methods of making PCB which is the toner transfer method.
A model servo or servomechanism isn’t anything more than just a small DC motor with a transmission and some electronics.