Lab2 Results

Part a)

2) a) V = IR

   5 = 0.02*R

   R = 5/0.02 = 250 ohms

   b) 220 ohms is minimum resistance since decreasing it greatly would increase the current leading to a damaged LED

   c) Rnage is 0.5 Ohms to 8.5 KOhms

3) a) No it dosent since they are all in series

4) a) 9 = 0.02*R

      R = 9/0.02 = 450 Ohms

Part b)

1) a) int ledPin =  11;  

   b) delay(2000);

2) a) const int buttonPin = 2;      

      const int ledPin =  9;   

   b) // check if the pushbutton is pressed.

  // if it is, the buttonState is HIGH:

  if (buttonState == LOW) {      

    // turn LED on:     

    digitalWrite(ledPin, HIGH);   

  }  

  else {

    // turn LED off:

    digitalWrite(ledPin, LOW);  

  }

3) a) int ledPin = 9;  

   b) Change the delay

Part c)

1) a) Assuming input of 5V and a max current of 20mA, R = 5/0.02 = 250 Ohms minimum resistance

LED Design Sketches

LED Design Prototype: Morse Code Communicator with LED's

Constructed a circuit with 2 buttons representing the dot and dash in Morse code. Correspondingly there are 2 LED's which light up when the respective button is pressed. Was done on the bread board, pictures as follow

LED Prototypes: (the quality of photos aren't the best since they were with a webcam). All descriptions are in the design sketches

1) Dining hall dishes which have LED's indicating whether veg or non-veg

Post Box which lights up when there is mail in it

LED watch, LED shirt, LED wall calender and pavement lined with LED's

LED embedded library book which flashes near the due date

LED laptop which flashes when you receive a new email, chat, facebook request etc

LED flash at night keychain to help find dropped keychains easily

Liquid containers with LED's displaying amount left and at what temperature