Raspberry Pi grimoire

initial setup

a raspberry PI is a small exposed computer.

list of materials:

1. Raspberry Pi 4 board (2GB version and it works perfectly fine for most projects)
   
2. Power supply for the Pi. For Raspberry Pi 4 you’ll need to power your board with an USB-C connector. For Raspberry Pi 2-3 you’ll need a micro-USB connector. Important: do not power on your Pi directly from your computer. This may seem to work, but the delivered current will be too low. Use a proper power supply, for example a smartphone power supply. So: - For Raspberry Pi 4, try using a power supply which can deliver 5V - 3.0A min - For Raspberry Pi 2 and 3: 5V - 2.5A min. If you can’t get those values, the minimum you should aim for is 5V - 2.0A
   
3. micro SD card 2 important criterions here: the class and the storage capacity. For the class, choose at least class 10. You should see a “10” inside a circle on the card. Some new cards are even more powerful, if you see a “3” inside a U shape it’s even better. If the class of your SD card is too low then it won’t be fast enough for the Raspberry Pi OS to run properly. For the storage capacity, choose at least 8GB, so you have enough space for the operating system and some additional files. 16/32GB is better especially if you plan on installing more software and store image/video files. You can go with more than 32GB but it might require some formatting from your side. In this course I personally use a 16GB micro SD card.
   

Hardware components
- 1* breadboard
- Set of wires: male-male, male-female, and female-female
- Set of resistors: 1kOhm, 10kOhm (if not available, resistors between 330Ohm and 20kOhm will do)
- 3* LEDs (any color)
- 1* push button (4 legs)

Note: for this list, usually you can find kits that include all those hardware components (search for “breadboard kit”).

Last edited by Moti Barski on Wed Mar 29, 2023 11:09 am; edited 1 time in total

warning

when manipulating Raspberry Pi, always:
1 shutdown the Pi from the desktop
2 wait 20 seconds and remove the power cable

Pi OS installation aka SD card flashing

1 https://www.raspberrypi.com/software/

Download and install Raspberry Pi Imager to a computer with an SD card reader.
Put the SD card you'll use with your Raspberry Pi into the reader and run Raspberry Pi
Imager.

this software will flash the raspberry OS into your SD card.
the software should be at least 1.7.2 for pi 4

2 connect the SD card to your computer, click choose Operating System and pick the
latest one.
click choose storage, and it should detect your SD card.

click setting and configure:
check enable SSH, use password auth.
(this will enable to access remotly (using the terminal) to the Pi,
without an external monitor)

and set a username and password.

on "configure wireless LAN": add the name and pass for your WiFi network
(internet router)

on "set local settings": set your timezone and keybouard language.

click on save

3 click on write, yes.

booting the Pi

make sure the power is off and no cables are connected.

plug in the SD card into the Pi.
connect the Pi to a power supply (not computer USB cable)

the green LED should blink randomly, meaning the Pi is booting.
a few seconds later the Pi will have connected to the WiFi network.

finding the Pi IP address

[URL unfurl="true"]https://angryip.org/[/URL]

go to downloads and choose your computers OS.
install angry IP scanner.

assuming your computer is connected to the same WiFi network,
in the angry IP scanner:
click on the icon next to start and add MAC vendor.

click IP and find a line that has wifi 192.168 or 10.0 and click it
so the IP range shows something like
192.168.31.0 to 192.168.31.255
edit the final numbers to 0 and 255 if they aren't set that way already.

click start, and wait about a minute.
if fire wall pops up, click allow.
clcik ping, sort by ping.
the blue circles mark findings, red mark no findings
you should see a blue dot and raspberry pi.local under host name, and the pi IP address.

connecting to the Pi via SSH

use mac terminal or

cmd on windows to SSH

or puTTy on windows:
[URL unfurl="true"]https://www.putty.org/[/URL]

ssh user_name(specified on the SD card flash stage by you)@IPaddress found by angry IP scanner
ssh pi@192.168.31.70

press enter. yes.
enter pi password you set up on flashing stage.

now you are in the Pi
pi@raspberrypi:~ $

VNC

it enables work with the Pi after SSH connection has been established from the computer.
on terminal after ssh pi@ip_address

sudo raspi-config
choose interface options, VNC, would you like VNC to be enabled?, yes
finish.

back on the terminal reboot the Pi:
sudo reboot

should say connection reset
wait 1 minute

ssh pi@ip_address
sudo raspi-config

system options, boot / auto login, desktop autologin, finish, reboot now? yes

should say connection reset on the terminal
wait 1 minute

ssh pi@ip_address
sudo raspi-config

display options, VNC resolution, chose the resolution of your computer screen
1920x1080 for full HD, finish, reboot now? yes.

get VNC at
[URL unfurl="true"]https://www.realvnc.com/en/connect/download/viewer/[/URL]
choose your computer OS

on VNC:
file, new connection,
VNC server : ip address of the Pi
name : does not matter
click ok, click Raspberry Pi, configure, enter the user name and pass of the PI
from the SD flash stage.

on VNC configurations

APPEARANCE:
raspberry Pi icon, preferences, appearance settings, task bar, very large,
system, font, set font size.

raspberry Pi icon, preferences, raspberry Pi configurations:
system, password : you can change the password, than reboot to apply.

on display you can change the resolution on VNC.

interfaces: from here you can enable SSH, VNC

localization: set timezone and keyboard language.

from the tool bar you can change wifi network, but than you will need to
find the new IP address on your computer that should be connected to the new wifi network.
than connect via SSH or VNC to the Pi.

click the update icon left of the bluetooth icon to update the Pi software, install updates.

powering off the Pi

menu (upper tool bar), Pi symbol, shutdown, wait a minute, now you can remove the power supply.

to power on make sure the SD card is in, then connect the power supply cable.

change Pi wifi settings

assuming your computer now uses a different wifi network
than the one in thePi settings.

power of the Pi, connect the SD card to your computer.
the SD card should have the name boot.

add a new file to config the wifi:

new text document, wpa_supplicant.conf

file contents:

country=US
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1

network={
scan_ssid=1
ssid="your_wifi_ssid"
psk="your_wifi_password"
}

ssid will be the wifi network name
psk will be the wifi network password

connect the SD card to the off powered Pi, turn on the Pi, wait a minute
open angry IP scanner to find the new Pi IP.
VNC, right click Raspberry PI, properties, update the new IP address, double click to connect.

hello world

on VNC
click raspberry Pi symbol, thonny python IDE, python IDE for beginners.
switch to regular mode, close the program and reopen it.

the view btn has a python shell option
>>> print("hello world")

above the shell there is a text editor for writting programs.
running the program prompts a save window, save as : hello_world.py
without spaces

GPIO

warnings

1. always turn off the Pi before changing a circuit
2. when power on, don't touch the Pi (static discharge (ESD))
3. start the circuit with GRD
4. don't use 5V on a GPIO pin (3.3V max)

LED blink program

pin output

GPIO Input pin

python code:

PIR sensor

PIR sensor



Passive InfraRed Sensor. it is a motion detector.

model used: HC-SR501

PIR setup

the PIR jumper should be set to high

the left potentiometer sets the detection range. turn counter clock wise
to decrease the range (3 meters) or clock wise up to (7 meters).

the right potentiometer sets the detection time, (how long a detection signal is sent).
minimum is counter clock wise.

max detection time lingers for 5 minutes, minimum lingers for 5 seconds



the sensor takes a minute to warm up after the Pi is powered on.

Pi OS task manager

Pi symbol, accessories, task manager