For the Arduino and Raspberry Pi there are some keypad matrixes that can be connected and read relatively easily. Similar to the numpad on a keyboard, these keypads have 3×4 or 4×4 keys. These modules can be used, for example, as code locks or for the construction of a small pocket calculator. With help of […]
Part 6 of the web server installation is about making the server available outside of the local network using a DNS server (such as No-IP, DynDNS).
In the field of Raspberry Pi soil moisture measurement, there are resistive and capacitive sensors, which each have advantages and disadvantages. The innovative Raspberry Pi casting machine / DFROBOT Gravity or “Giess-o-Mat” sensor provides a permanently accurate capacitive measurement, which a.o. in our Raspberry Pi greenhouse can be very interesting. This tutorial is about the structure […]
If you have several smaller or one larger project, you will soon discover that the GPIO pins of the Raspberry are fastly becoming too little. For all of you, this tutorial will show you how to use an I2C Port Expander to easily multiply the GPIO pins many times over.
In some applications, it is important that the Pi continues to be powered in the event of a power outage. If something is written on the SD card at the moment of power interruption, it is possible that the image will become corrupt and thus unusable. A UPS (Uninterruptible Power Supply) ensures that if a […]
To use, for example, a weather station, it is important to know the brightness. With a Raspberry Pi light sensor (photoresistor/brightness sensor), it is very easy to determine a value, which can say, for example, if it is day, twilight or night. In turn, projects could be implemented to control the (exterior) lights, which turn […]
The Raspberry Pi can be used pretty much for any conceivable application – as well as a radio transmitter. Frequencies from 1Mhz to 250Mhz can be used, including the usual radio frequencies between 88 and 108Mhz. Depending on the position and antenna, the signal can be transmitted up to 100 meters. In this tutorial, I […]
With the release of the Raspberry Pi 2, Microsoft had announced they will provide a version of Windows 10 for the Pi. This has happened now. According to Microsoft, this is only possible with the PC version of Win 10, but it also works on Windows 8.1, as I show in this tutorial. Windows 10 […]
There are some sensors for the Raspberry Pi that can measure humidity, temperature and other values. Nevertheless, these modules are almost exclusively suitable for the air and not intended for use in the earth. For some projects, such as an automatic plant supply, the moisture of the soil must be measured, then, e.g. refilled with […]
Anyone who has dealt with image processing in relation to the Raspberry Pi will sooner or later come across the OpenCV library. It provides many very useful features such as face recognition, the creation of depth maps (stereo vision, optical flow), text recognition or even for machine learning. In addition, OpenCV (Open Source Computer Vision) […]
Often you want to control modules with a higher voltage with the Raspberry Pi. For this purpose, relays can be used on the Raspberry Pi: The relay “switch” is utilized by means of a low-voltage pulse. Since the Pi only tolerates a maximum of 5V (the GPIOs even only 3.3V) without relays, there is the […]
