Raspberry pi

Syntax:- 

What is Raspberry pi

Types of this

How to install

light blink

traffic light project

IR sensor connect to pi

LDR sensor connect to pi

Camera connect to pi

Raspberry pi - 

A Raspberry Pi is a small computer that can run a full operating system (usually Linux). It has more power and features than a microcontroller, like USB ports, HDMI output, Wi-Fi, and the ability to run complex software.

There are various types of  Raspberry pi model

1. Raspberry Pi 4 Model B
2. Raspberry Pi 3 Model B+
3. Raspberry Pi 3 Model B
4. Raspberry Pi Zero 2 W
5. Raspberry Pi Zero W
6. Raspberry Pi 400
7. Raspberry Pi Pico

How to install Raspberry pi 4 

•  Go to google and paste this link https://www.raspberrypi.com/softwar
• Clink on Download
  

• install this imager
• 
  
  

• insert SD card in card reader and connect to computer and click on choose storage.
•  After process remove SD card and put in Raspberry pi
• And connect Raspberry pi to monitor/computer/laptop by HDMI cable and c-type cable, Now you can use Raspberry pi.

Light blink code for pi

from gpiozero import LED 

from time import sleep

led = LED(17)  # Connect LED to GPIO 17

while True:

    led.on()

    sleep(1)

    led.off()

    sleep(1)

//gpiozero is a Python library that makes it very easy to use the GPIO (General Purpose Input Output) pins on a Raspberry Pi.

Traffic light project:-

import RPi.GPIO as GPIO

import time

# Set GPIO mode

GPIO.setmode(GPIO.BCM) #Broadcom SoC (chip) numbering

# Assign GPIO pins

RED = 17

YELLOW = 27

GREEN = 22

# Set up pins as output

GPIO.setup(RED, GPIO.OUT)

GPIO.setup(YELLOW, GPIO.OUT)

GPIO.setup(GREEN, GPIO.OUT)

def traffic_light_cycle():

    while True:

        # Green light on

        GPIO.output(GREEN, True)

        GPIO.output(YELLOW, False)

        GPIO.output(RED, False)

        time.sleep(5)

        

        # Yellow light on

        GPIO.output(GREEN, False)

        GPIO.output(YELLOW, True)

        time.sleep(2)

        

        # Red light on

        GPIO.output(YELLOW, False)

        GPIO.output(RED, True)

        time.sleep(5)

try:

    traffic_light_cycle()

except KeyboardInterrupt:

    print("Traffic light simulation stopped by user.")

finally:

    GPIO.cleanup()

IR sensor connect to Raspberry pi

   import RPi.GPIO as GPIO

import time

# Pin definitions

IR_SENSOR = 17  # GPIO pin number

# Setup

GPIO.setmode(GPIO.BCM)

GPIO.setup(IR_SENSOR, GPIO.IN)

print("IR Sensor Test (press Ctrl+C to exit)") #optional 

try:

    while True:

        if GPIO.input(IR_SENSOR) == 0:

            print("Object detected!")

        else:

            print("No object.")

        time.sleep(0.5)

except KeyboardInterrupt:

    print("Program stopped.")

finally:

    GPIO.cleanup()

 

Motor connect to Raspberry pi :-

import RPi.GPIO as GPIO

import time

# Pin definitions

IN1 = 17

IN2 = 18

IN3 = 22

IN4 = 23

# Setup

GPIO.setmode(GPIO.BCM)

GPIO.setup(IN1, GPIO.OUT)

GPIO.setup(IN2, GPIO.OUT)

GPIO.setup(IN3, GPIO.OUT)

GPIO.setup(IN4, GPIO.OUT)

def stop():

    GPIO.output(IN1, False)

    GPIO.output(IN2, False)

    GPIO.output(IN3, False)

    GPIO.output(IN4, False)

def forward():

    GPIO.output(IN1, True)

    GPIO.output(IN2, False)

    GPIO.output(IN3, True)

    GPIO.output(IN4, False)

def backward():

    GPIO.output(IN1, False)

    GPIO.output(IN2, True)

    GPIO.output(IN3, False)

    GPIO.output(IN4, True)

def left():

    GPIO.output(IN1, False)

    GPIO.output(IN2, True)

    GPIO.output(IN3, True)

    GPIO.output(IN4, False)

def right():

    GPIO.output(IN1, True)

    GPIO.output(IN2, False)

    GPIO.output(IN3, False)

    GPIO.output(IN4, True)

try:

    print("Moving Forward")

    forward()

    time.sleep(3)

    stop()

    time.sleep(60)

    print("Moving Backward")

    backward()

    time.sleep(3)

    stop()

    time.sleep(60)

    print("Turning Left")

    left()

    time.sleep(1.5)

    stop()

    time.sleep(60)

    print("Turning Right")

    right()

    time.sleep(1.5)

    stop()

    time.sleep(60)

except KeyboardInterrupt:

    print("Stopped by user.")

finally:

    stop()

    GPIO.cleanup()

Ultrasonc Code in pi

import RPi.GPIO as GPIO

import time

# Pin Definitions

TRIG = 23

ECHO = 24

GPIO.setmode(GPIO.BCM)

GPIO.setup(TRIG, GPIO.OUT)

GPIO.setup(ECHO, GPIO.IN)

def measure_distance():

    # Send 10us pulse to trigger

    GPIO.output(TRIG, True)

    time.sleep(0.00001)

    GPIO.output(TRIG, False)

    start_time = time.time()

    stop_time = time.time()

    # Wait for Echo pin to go HIGH

    while GPIO.input(ECHO) == 0:

        start_time = time.time()

    # Wait for Echo pin to go LOW

    while GPIO.input(ECHO) == 1:

        stop_time = time.time()

    # Calculate pulse duration

    elapsed = stop_time - start_time

    # Calculate distance (speed of sound = 34300 cm/s)

    distance = (elapsed * 34300) / 2

    return distance

try:

    while True:

        dist = measure_distance()

        print(f"Distance: {dist:.2f} cm")

        time.sleep(1)

except KeyboardInterrupt:

    print("Measurement stopped by user.")

finally:

    GPIO.cleanup()

Servo connect to pi

import RPi.GPIO as GPIO

import time

servo_pin = 18

GPIO.setmode(GPIO.BCM)

GPIO.setup(servo_pin, GPIO.OUT)

pwm = GPIO.PWM(servo_pin, 50)  # 50Hz frequency

pwm.start(0)

def set_angle(angle):

    duty = 2 + (angle / 18)  # Convert angle to duty cycle

    pwm.ChangeDutyCycle(duty)

    time.sleep(0.5)

    pwm.ChangeDutyCycle(0)  # Stop sending signal to avoid jitter

try:

    set_angle(45)  # Move servo to 45 degrees

    time.sleep(2)  # Wait for 2 seconds to hold position

finally:

    pwm.stop()

    GPIO.cleanup()