Arduino Lab 2: Temperature Display

Background: We may want to use a single LED to represent a single data point, say the temperature of our patient. RGB LEDs are a great candidate for this. It is essentially 3 LEDs in one package: a red LED, a green LED, and a blue LED. We could use green to represent a normal temperature, blue to represent too cold, and red to represent too hot.

Goal: Cycle through all 4 states of an RGB LED.

 

Circuit Setup

• 1x RGB LED
• 3x Series Resistors (220 Ohms or 330 Ohms)
• Connect each individual color with a series resistor to a digital pin.

 

Lab Instructions

• Configure the 3 digital pins as outputs.
• We want to cycle through all states of the LED.
  • Turn LED red, green, blue, then off.
  • Remain in each state for 500 ms.

 

Optional Extension

Background: We may want to be able to display more than 4 different statuses (off, red, green, blue). Let's investigate how we can get even more out of our RGB LEDs.

Goal: Test out color mixing with an RGB LED.

• Are there more than the 4 states? How many?
• Try to turn on multiple LEDs at once and cycle through all the states.