1. Digital Input from Switches

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3. Arduino Arduino Wiring the Switch switch not pressed ANALOG DIGITAL
RESET
3V3
5V Gnd Vin
AREF
GND
DIGITAL
POWER
Arduino
10kW
ANALOG
RESET
3V3
5V Gnd Vin
AREF
GND
DIGITAL
POWER
Arduino
10kW
switch pressed

4. Arduino Why the 10kΩ Resistor?
Using a large resistance limits the current so that we don’t waste electricity!
ANALOG
RESET
3V3
5V Gnd Vin
AREF
GND
DIGITAL
POWER
Arduino
10kW
switch
𝑃=𝑉∙𝐼= 𝑉 2 𝑅 = 5𝑉 ,000Ω =0.0025W=2.5mW
. . . any resistor will do, but there’s no sense in wasting power

5. (direct connection to power)
Use a Digital Input to Sense When Switch is Pressed
ANALOG
RESET
3V3
5V Gnd Vin
AREF
GND
DIGITAL
POWER
Arduino
10kW
switch
digitalRead(7)
check status of pin 7 using . . .
void setup(){
pinMode(7,INPUT);
Serial.begin(9600); }
void loop(){
Serial.print(digitalRead(7));
switch status
voltage
at pin 7
status of
digital input 7
open
(not pressed) 0V
(no power applied)
LOW or 0
closed
(pressed) 5V
(direct connection to power)
HIGH or 1

6. Run Power Wires to Breadboard Bus Strips
cut and strip jumper wires to connect the second bus strip to the first one
red to 5V black to GND
red wire to +
black wire to -
Clean Wiring is Good!
twisted red & black wires from your kit

7. Arduino Wire a Switch and Enter the Sketch to See if it Works! NO COM
These three wires are connected
COM prong from switch
NO prong from switch
ANALOG
RESET
3V3
5V Gnd Vin
AREF
GND
DIGITAL
POWER
Arduino
10kW
switch
void setup(){
pinMode(7,INPUT);
Serial.begin(9600); }
void loop(){
Serial.println(digitalRead(7));
COM NO