robotics

LED

Light Emitting Diode

LED, resistor

LEDs need a resistor to limit current.

Too much current

LED burns out

Resistor function

Protect components

Voltage

Electrical pressure

Current

Flow of electric charge

Power

Depends on voltage and current

Higher voltage/current

Higher power

Digital Signals

Only two states: HIGH or LOW

Digital Signals

ON/OFF or 1/0

Analog Signals

Gradual, continuous values

Analog Signals

Used for dimming and speed control

Pins with ~ (tilde)

Support PWM

PWM

Pulse Width Modulation

PWM

Digital, but behaves like analog

PWM

Controls LED brightness, motor or fan speed

PWM Key Idea

Longer HIGH time = brighter LED / faster motor

PWM Key Idea

Shorter HIGH time = dimmer LED / slower motor

Potentiometer

Variable resistor

Potentiometer

Used to control voltage

Potentiometer types

Rotary (knob) and Linear (slider)

Wiper (potentiometer)

Movement → voltage change

Arduino function for Potentiometer

analogRead()

Serial Monitor

Used to display values from Arduino

Serial Monitor

Must use Serial.begin(9600)

Serial Monitor

Without it: No output

Seven-Segment Display - Odd number

RED

Seven-Segment Display - Even number

GREEN

Seven-Segment Display - Letter

YELLOW

PWM

≠ true analog

Analog

Smooth control

Digital

ON or OFF only

Potentiometers give

analog input

Sensors often use

analog pins