The Raspberry Pi OS, like any other operating system, is always doing some form of reading and write executions even when it is running idle. If suddenly the power to the Raspberry Pi board is interrupted, there is a great chance that the OS file system gets corrupted. This is the reason why the Raspberry Pi OS needs to be shut down properly.
To learn more about the Raspberry Pi boards, read the introductory article here.
Raspberry Pi OS Startup and Shutdown
There are several ways to shutdown the Raspberry Pi OS:
- Using the Desktop Graphical User Interface (GUI)
- Via the Terminal
- By configuring a pair of GPIO pins to initiate a shutdown script.
For the startup, if you use the first two options, you need to remove the power supply from the wall socket or from the USB-C port and reconnect again.
This tutorial will focus on the last option. We will connect a push button to two pins on the GPIO to shutdown and startup the Raspberry Pi.
This tutorial does not actually power-down the Raspberry Pi board. It only puts the system to standby mode and consumes minimal power. To actually power-down the board, you need to initiate shutdown via the Desktop GUI or execute the shutdown command on the Terminal.
For this tutorial, we will use the following:
On the Raspberry Pi, we will use GPIO3 (pin 5) and GND to connect the push button. You can use any Ground pin available on the Raspberry Pi GPIO header.
One terminal of the push button must connect to GND, and the other terminal to GPIO3. It doesn’t matter which terminal of the push button you will connect to GND and GPIO3 as long as they make contact when the button is pressed.
Configuring the Raspberry Pi OS
To make the push button work as intended, we need to modify the Raspberry Pi OS’s config. txt file. We can do this by opening a terminal and entering the following command.
sudo nano /boot/config.txt
The above command will open config.txt file using the Nano text editor. Scroll down at the end of the file and add the following in a new line.
After adding the line, save it by pressing
ENTER to overwrite existing file, and press
X to exit editor.
dtoverlay=gpio-shutdown in config.txt, we are configuring the Raspberry Pi to use GPIO3 as a startup and shutdown signal.
By pressing the button, we are connecting to the Ground. This action pulls the GPIO3 to
LOW and causes the Raspberry Pi OS to shutdown or startup depending on its current state.
Apply power to the Raspberry Pi 4B and wait for it to finish its booting sequence. Press the button to shutdown the Raspberry Pi board. To startup, press the button again.
Congratulations! You now have a physical button to startup and shutdown your raspberry Pi 4B.