Embedded Systems [II]

An Electronic circuit is a complete circular path that electricity flows through. It directs and controls electric current to perform various functions.

Electrical components:These are elements in electrical circuits that perform specific functions to control, regulate, or manipulate
the flow of electric current.

These components can be classified into two :

Active components are electronic devices that can control the flow of electrical current.
They require a power source to operate and can amplify, switch, or generate electrical signals.
They include transistors,micro-controllers

Passive components are electronic devices that do not require a power source to perform their specified function.
They do not control the flow of electrical current but instead modify or store it.
They include resistors, capacitors, inductors, transformers, and diodes.

A circuit has three essential components that work together to enable current flow:

a conductive path- a pathway for current to pass through...wire
a power source-for providence of electrical energy(battery)
a load-any device that needs electric power to operate

Traffic lights using LEDS with PI PICO

with the code below:

from machine import Pin from time import sleep




one= Pin(0,Pin.OUT)

two= Pin(1,Pin.OUT)

three= Pin(2,Pin.OUT)

 #button=Pin(1,Pin.IN,Pin.PULL_UP)

 while True:
    
    one.value(1)

    two.value(0)

    three.value(0)
    
    
    one.value(0)

    two.value(1)

    three.value(0)
    
    
    one.value(0)

    two.value(0)

    three.value(1)


>

Controlling an LED using pushbutton

from machine import Pin

        from utime import sleep_ms

          
          button = Pin(0, Pin.IN, Pin.PULL_UP) #Internal pull-up

          led = Pin(1, Pin.OUT)

          State = 0 
          
          if __name__ == '__main__':

              while True:

                  print(button.value())

                  if button.value() == 0: #key press

                      if State == 0:

                          led.value(1)

                          sleep_ms = 100

                          while button.value() == 0:

                              State = 1

                      else:

                          led.value(0)

                          sleep_ms = 100

                          while button.value() == 0:

                              State = 0

   
Sensor- a device that detect/ senses physical phenomenon then reacts to it in a particular way.
It converts physical attributes to electric signal.
eg..Ultrasonic sensor which sends out soundwaves and measures the time it takes for the sound to be reflected back.
Actuator- is a part of a device that achieves physical movement by converting energy to mechanical force.
It controls movement or positioning.
An actuator recieves and acts on the information given.Initially it relies on the sensor for info inorder for it to work.
   

Here is a simple project using an ultrasonic sensor

from machine import Pin

  import utime

  trigger = Pin(3, Pin.OUT)

  echo = Pin(2, Pin.IN)

  led =Pin(4, Pin.OUT)

  buzzer= Pin(5, Pin.OUT)

  led.value(0)

  buzzer.value(0)
  
  def ultra():

      trigger.low()

      utime.sleep_us(2)

      trigger.high()

      utime.sleep_us(5)

      trigger.low()
  
      while echo.value() == 0:

          signaloff = utime.ticks_us()
  
      while echo.value() == 1:
  
      
timepassed = signalon - signaloff

      distance = (timepassed * 0.0343) / 2

      return distance

  
while True:

           measured_distance = ultra()

               if measured_distance <= 50:

                 print("The distance from the object is ", measured_distance, "cm")

                  led.value(1)

                    buzzer.value(1)

                      utime.sleep(1)

                        led.value(0)

                          buzzer.value(0)

                             break
                             
utime.sleep(1)

MODULE 2

Embedded Systems [II]