Raspberry Pi

• User : pi
• Pass : raspberry

$ sudo raspi-config

Go to Interface Options then SSH and activate it. No reboot is required.

It is good practice to have your router assign a static IP address to a RPi if you want to regularly connect to it via ssh

$ sudo raspi-config

Go to Interface Options then Camera and activate it. Raspi-config will propose a reboot which should be accepted.

Modify the /etc/rc.local file (requires sudo)

$ sudo nano /etc/rc.local

Before the 'exit 0' line at the end insert lines like this one :

bash /path/to/script.sh

$ cat /sys/class/thermal/thermal_zone0/temp

Divide by 1000 to get °C format

$ vcgencmd measure_temp
$ /opt/vc/bin/vcgencmd measure_temp (Full Path)

These measures were done on a Rapsberry Pi 4 running Raspbian with no heavy-duty program running, no screen or USB devices attached and at a room temperature around 20°C

• With a 5V fan connected to 5V the temperature is stable around 35-38°C. Fan is loud and disturbing
• With a 5V fan connected to 3.3V the temperature is stable around 41-42°C
• With no fan connected the temperature is stable around 55-58°C

GPIO Header

# Exports pin to userspace
$ echo "18" > /sys/class/gpio/export                  
 
# Sets pin 18 as an output
$ echo "out" > /sys/class/gpio/gpio18/direction
 
# Sets pin 18 to high
$ echo "1" > /sys/class/gpio/gpio18/value
 
# Sets pin 18 to low
$ echo "0" > /sys/class/gpio/gpio18/value 
 
# Exports pin to userspace
$ echo "4" > /sys/class/gpio/export
 
# Sets pin 4 as an input
echo "in" > /sys/class/gpio/gpio4/direction
 
# Read value of pin 4
cat /sys/class/gpio/gpio4/value