The Banana PI Zero has only 500 MB Ram. Armbian keeps the /tmp directory in a Ram Disk which has only 197884 bytes available: So I ended up with the following errors when I tried to install pyspark, numpy or other bigger libraries: Memory Error [Errno 28] No space left on device socket.timeout: The read operation timed out It seems to be more reliable to install the library with apt if it is available: apt Read more…
I liked the Spec of the Banana PI Zero: With it’s quad-core Cortex-A7 it should have more power then the Raspberry PI Zero – it should just have more memory! It is quite easy to set up a Raspberry PI in a way that it starts and automatically connects to the network. So there is no need for any screen or keyboard. I tried to install some of the supported Operating Systems on the Banana Read more…
I was building a small Remote Control for my RC toys with the help of a ESP32. This Microcontroller is the perfect choice because – it supports enough analog input pins (we need at least 4) – We can use Bluetooth or UDP as Communication Protocol out of the box – It can be programmed with the Arduino IDE – so this is pretty simple to use. I used the following components Joystick I am Read more…
Spectrum Satellite API for Arduino I was working on a small project to implement the Spectrum Satellite Receiver Protocol on an Arduino. The project should work with any type of board (e.g. Arduinos, ESP32, ESP8266 etc) Complete Implementation of the Spektrum Satellite Specification Support for sending data e.g. to build a Remote Control Transmitter Support for receiving data e.g. to build a Remote Control Receiver Support of different data types and automatic scaling of channel Read more…
I needed to print some Springs in OpenSCAD. To simplify my work I have written a very small, simple and efficient library that I have described in the following Gist. The source code is also available on Github. This demo has been written in Jupyterlab using my OpenSCAD Kernel.
It is very easy to control servos with the help of the Servo Library which is part of Arduino. For my tests I was using an ESP8266.to evaluate the following small Servos: 1.5g 180 Degree Nylon Gear Digital Linear Micro Servo 3.7V-5V For Micro RC Airplane – left 1.7g Low Voltage Micro Digital Servo Mini JST 1.25Pin Connector for RC Mode 3.7g Micro Digital Servo GH-S37D For RC Airplane Helicopter I wanted to investigate the expected Read more…
I am planning to design and build a 3D printed RC Airplane. To shortcut the “Remote Control” functionality I bought a second hand Spectrum DX 6i that I wanted to use together with a Spektrum Satellite Receiver: These Receiver Boards are quite small and it should be quite easy to use them together with an Arduino compatible board that uses a 3.3V logic. The Spektrum Satellites uses a serial data line.which can be read from Read more…
Quite some time ago I bought some cheap DRV8833 Motor Controller Boards (HW-627) from China and now I planned to use them in one of my projects. I was struggling quite a bit to figure out how this is working. This board is using the DRV8833 chip and can control 2 motors in parallel. Specifications: Product size: 18.5*16mm/0.73*0.63″ Input voltage: 3-10V Single H bridge Output current: 1.5A, can drive 2 DC geared motors Uses: It Read more…
Overview I was playing with the idea to implement a simple Synthesizer for the ESP32.which would play different instruments. The ESP32 should have enough power to generate interesting sounds. The limitation however is on the memory. So any approach which relies on sampled data and big sound buffers will just not work. Therefore we need to rely on playing the generated sounds as directly as possible. A Synthesizer is an electronic musical instrument that generates audio Read more…
In the last couple of blogs I was setting the stage for my Radio Music Player for the ESP32. I was thinking first that I will use one of the many existing web based music applications together with my ESP32 Bluetooth Player. But I soon realised that either they want my money or bombard me with annoying commercials! My GUI was written with Vue.js and I am using radiobrowser-api-rust to find the Radio Stations – Read more…