1. Arduino Microcontroller Workshop UMBC Institute of Electrical and Electronics Engineers
Arduino UMBC IEEE
Sekar Kulandaivel
Week 2: Arduino Programming with Piezo
Technical Skills Series Presentation
April 8th – 9th, 2014

2. Topics to Cover
Arduino Coding Basics & Functions Analog & Digital Signals Piezoelectric Sensors Pulse Width Modulation

3. Color 1st Digit 2nd Digit Multiplier
4th band is Tolerance. L R
Color
1st Digit
2nd Digit
Multiplier
Black
100
Brown 1
101
Red 2
102
Orange 3
103
Yellow 4
104
Green 5
105
Blue 6
106
Violet 7
107
Gray 8
108
White 9
109

4. 330Ω 3
x =
10kΩ 1
x =
2kΩ 2
x =
1MΩ 1
x =

5. Made with Fritzing.org

6. Important Functions
int val, time; void setup() { … } void loop() { … } Serial.begin(9600); Serial.print(“Hello”); Serial.println(“Hi”); delay(1000);
pinMode(8, INPUT);
pinMode(9, OUTPUT);
val = digitalRead(8);
digitalWrite(9, out);
val = analogRead(A0);
analogWrite(9, out);
time = millis();
map(var, testLow, testHigh, mapLow, mapHigh);
tone(8, pitch, time);

7. const int sensorPin = 8; int sensorValue; void setup() { Serial
const int sensorPin = 8; int sensorValue; void setup() { Serial.begin(9600); pinMode(sensorPin, INPUT); } void loop() { sensorValue = digitalRead(sensorPin); Serial.println(sensorValue); delay(25);

8. const int sensorPin = 8; const int outputPin = 9; int sensorValue; void setup() { Serial.begin(9600); pinMode(sensorPin, INPUT); pinMode(outputPin, OUTPUT); } void loop() { sensorValue = digitalRead(sensorPin); Serial.println(sensorValue); if (sensorValue == HIGH) { digitalWrite(outputPin, HIGH); delay(500); digitalWrite(outputPin, LOW); delay(25);

9. const int sensorPin = A0; const int outputPin = 9; int sensorValue; void setup() { Serial.begin(9600); pinMode(sensorPin, INPUT); pinMode(outputPin, OUTPUT); } void loop() { sensorValue = analogRead(sensorPin); Serial.println(sensorValue); analogWrite(outputPin, sensorValue); delay(25);

10. const int sensorPin = A1; const int outputPin = 9; int sensorValue; int low = 300; int high = 450; int range[2] = {0, 255}; void setup() { Serial.begin(9600); pinMode(sensorPin, INPUT); pinMode(outputPin, OUTPUT); } void loop() { sensorValue = analogRead(sensorPin); Serial.println(sensorValue); sensorValue = map(sensorValue, low, high, range[0], range[1]); analogWrite(outputPin, sensorValue); delay(25);

11. const int sensorPin = A1; const int outputPin = 11; int wait = 25; int sensorValue, pitch; int range[2] = {1023, 0}; int minTone = 500; int maxTone = 1500; void setup() { Serial.begin(9600); pinMode(sensorPin, INPUT); pinMode(outputPin, OUTPUT); while (millis() < 3000) { sensorValue = analogRead(sensorPin); if (sensorValue < range[0]) { range[0] = sensorValue; } if (sensorValue > range[1]) { range[1] = sensorValue; }

12. void loop() { sensorValue = analogRead(sensorPin); Serial
void loop() { sensorValue = analogRead(sensorPin); Serial.println(sensorValue); pitch = map(sensorValue, range[0], range[1], minTone, maxTone); tone(outputPin, pitch, wait); delay(wait); }

13. Challenge Requirements: Sense a knock using the piezoelectric sensor.
Flash LED once for a soft knock.
Flash LED twice for a loud knock.
Analog
Notes:
Remove photoresistor and potentiometer circuits from your board.
Knock on the breadboard or tap the piezo for the best results.
Utilize previous code as a guide for your project.