56 January & February 2021 http://www.elektormagazine.com
The Raspberry Pi will act as the base node of the RF24 network and
is responsible for processing the sensor values it receives from the
Arduino node (or nodes, if you have more than one). [The Arduino
node is described in preceding chapters in the book not excerpted
here, Ed.]. In this chapter, I will show you how to connect the RF24
module to the Raspberry Pi. You can choose to do the wiring on
a breadboard, or to use a special HAT I designed for this purpose.
I implemented my Raspberry Pi RF24 module using the HAT break-
out. You can see it in action in Figure 1. The HAT accommodates
the nRF24 transceiver module, the DHT22, a momentary button,
and two LEDs (power indicator, and activity indicator). You can
download the Gerber files for the HAT from the project’s part list
page [1]. You can also order this PCB directly from PCBWay [2].If you prefer to prototype this circuit using the breadboard, please
consult the connections table in Figure 2, and the schematic
diagram of the HAT PCB in Figure 3. You can get a high-resolution
version of the HAT schematic from the same project parts list [3].In the following list I include all the parts that you will need to
implement that schematic diagram of Figure 2. With some of
these parts, such as the button and DHT22 sensor, you have alreadyRaspberry Pi Full Stack
RPi and RF24 at the Heart of a Sensor Network
By Dr. Peter Dalmaris (Australia)This installment of Elektor Books presents roughly two
chapters excerpted from Peter Dalmaris’ book Raspberry Pi
Full Stack recently published by Elektor. Aimed at inquisitive
RPi users keen to link hardware and software on their learn-
by-doing journey, the book has a wealth of educational
material to offer. Here’s a ‘day trip’ described in fine detail:
combining an RPi with an RF24 module to read values from
remote sensors incorporated in a small network.elektor books
Figure 1: The Raspberry Pi HAT installed on a Raspberry Pi Zero W. Figure 2: The connection details for the nRF24 and DHT22 modules.