Workshops/Arduino for beginners 2/Code
From London Hackspace Wiki
Arduino Workshop
London Hackspace
22nd/23rd January 2011
Mike McRoberts
LED Flasher
// Project 1 - LED Flasher
int ledPin = 10;
void setup() {
pinMode(ledPin, OUTPUT);
}
void loop() {
digitalWrite(ledPin, HIGH);
delay(1000);
digitalWrite(ledPin, LOW);
delay(1000);
}
Interactive Traffic Lights
// Project 2 - Interactive Traffic Lights
int carRed = 12; // assign the car lights
int carYellow = 11;
int carGreen = 10;
int pedRed = 9; // assign the pedestrian lights
int pedGreen = 8;
int button = 2; // button pin
int crossTime = 5000; // time alloyoud to cross
unsigned long changeTime; // time since button pressed
void setup() {
pinMode(carRed, OUTPUT);
pinMode(carYellow, OUTPUT);
pinMode(carGreen, OUTPUT);
pinMode(pedRed, OUTPUT);
pinMode(pedGreen, OUTPUT);
pinMode(button, INPUT); // button on pin 2
// turn on the green light
digitalWrite(carGreen, HIGH);
digitalWrite(pedRed, HIGH);
}
void loop() {
int state = digitalRead(button);
/* check if button is pressed and it is over 5 seconds since last button press */
if (state == HIGH && (millis() - changeTime) > 5000) {
// Call the function to change the lights
changeLights();
}
}
void changeLights() {
digitalWrite(carGreen, LOW); // green off
digitalWrite(carYellow, HIGH); // yellow on
delay(2000); // wait 2 seconds
digitalWrite(carYellow, LOW); // yellow off
digitalWrite(carRed, HIGH); // red on
delay(1000); // wait 1 second till its safe
digitalWrite(pedRed, LOW); // ped red off
digitalWrite(pedGreen, HIGH); // ped green on
delay(crossTime); // wait for preset time period
// flash the ped green
for (int x=0; x<10; x++) {
digitalWrite(pedGreen, HIGH);
delay(250);
digitalWrite(pedGreen, LOW);
delay(250);
}
// turn ped red on
digitalWrite(pedRed, HIGH);
delay(500);
digitalWrite(carYellow, HIGH); // yellow on
digitalWrite(carRed, LOW); // red off
delay(1000);
digitalWrite(carGreen, HIGH);
digitalWrite(carYellow, LOW); // yellow off
// record the time since last change of lights
changeTime = millis();
// then return to the main program loop
}
LED chaser
// Project 3
byte ledPin[] = {4, 5, 6, 7, 8, 9, 10, 11, 12, 13}; // Create array for LED pins
int ledDelay; // delay between changes
int direction = 1;
int currentLED = 0;
unsigned long changeTime;
int potPin = 2; // select the input pin for the potentiometer
void setup() {
for (int x=0; x<10; x++) { // set all pins to output
pinMode(ledPin[x], OUTPUT); }
changeTime = millis();
}
void loop() {
ledDelay = analogRead(potPin); // read the value from the pot
if ((millis() - changeTime) > ledDelay) { // if it has been ledDelay ms since
last change
changeLED();
changeTime = millis();
}
}
void changeLED() {
for (int x=0; x<10; x++) { // turn off all LED's
digitalWrite(ledPin[x], LOW);
}
digitalWrite(ledPin[currentLED], HIGH); // turn on the current LED
currentLED += direction; // increment by the direction value
// change direction if we reach the end
if (currentLED == 9) {direction = -1;}
if (currentLED == 0) {direction = 1;}
}
Mood Lamp
// Project 4 - Mood Lamp
float RGB1[3];
float RGB2[3];
float INC[3];
int red, green, blue;
int RedPin = 11;
int GreenPin = 10;
int BluePin = 9;
void setup()
{
randomSeed(analogRead(0));
RGB1[0] = 0;
RGB1[1] = 0;
RGB1[2] = 0;
RGB2[0] = random(256);
RGB2[1] = random(256);
RGB2[2] = random(256);
}
void loop()
{
randomSeed(analogRead(0));
for (int x=0; x<3; x++) {
INC[x] = (RGB1[x] - RGB2[x]) / 256; }
for (int x=0; x<256; x++) {
red = int(RGB1[0]);
green = int(RGB1[1]);
blue = int(RGB1[2]);
analogWrite (RedPin, red);
analogWrite (GreenPin, green);
analogWrite (BluePin, blue);
delay(100);
RGB1[0] -= INC[0];
RGB1[1] -= INC[1];
RGB1[2] -= INC[2];
}
for (int x=0; x<3; x++) {
RGB2[x] = random(556)-300;
RGB2[x] = constrain(RGB2[x], 0, 255);
delay(1000);
}
}
Serial controlled mood lamp
// Project 5 - Serial controlled mood lamp
char buffer[18];
int red, green, blue;
int RedPin = 11;
int GreenPin = 10;
int BluePin = 9;
void setup()
{
Serial.begin(9600);
Serial.flush();
pinMode(RedPin, OUTPUT);
pinMode(GreenPin, OUTPUT);
pinMode(BluePin, OUTPUT);
}
void loop()
{
if (Serial.available() > 0) {
int index=0;
delay(100); // let the buffer fill up
int numChar = Serial.available();
if (numChar>15) {
numChar=15;
}
while (numChar--) {
buffer[index++] = Serial.read();
}
splitString(buffer);
}
}
void splitString(char* data) {
Serial.print("Data entered: ");
Serial.println(data);
char* parameter;
parameter = strtok (data, " ,");
while (parameter != NULL) {
setLED(parameter);
parameter = strtok (NULL, " ,");
}
// Clear the text and serial buffers
for (int x=0; x<16; x++) {
buffer[x]='\0';
}
Serial.flush();
}
void setLED(char* data) {
if ((data[0] == 'r') || (data[0] == 'R')) {
int Ans = strtol(data+1, NULL, 10);
Ans = constrain(Ans,0,255);
analogWrite(RedPin, Ans);
Serial.print("Red is set to: ");
Serial.println(Ans);
}
if ((data[0] == 'g') || (data[0] == 'G')) {
int Ans = strtol(data+1, NULL, 10);
Ans = constrain(Ans,0,255);
analogWrite(GreenPin, Ans);
Serial.print("Green is set to: ");
Serial.println(Ans);
}
if ((data[0] == 'b') || (data[0] == 'B')) {
int Ans = strtol(data+1, NULL, 10);
Ans = constrain(Ans,0,255);
analogWrite(BluePin, Ans);
Serial.print("Blue is set to: ");
Serial.println(Ans);
}
}
Piezo Sounder Alarm
// Project 6 - Piezo Sounder Alarm
float sinVal;
int toneVal;
void setup() {
pinMode(8, OUTPUT);
}
void loop() {
for (int x=0; x<180; x++) {
// convert degrees to radians then obtain sin value
sinVal = (sin(x*(3.1412/180)));
// generate a frequency from the sin value
toneVal = 2000+(int(sinVal*1000));
tone(8, toneVal);
delay(2);
}
}
Light Sensor
// Project 7 - Light Sensor
int piezoPin = 8; // Piezo on Pin 8
int ldrPin = 0; // LDR on Analog Pin 0
int ldrValue = 0; // Value read from the LDR
void setup() {
// nothing to do here
}
void loop() {
ldrValue = analogRead(ldrPin); // read the value from the LDR
tone(piezoPin,1000); // play a 1000Hz tone from the piezo
delay(25); // wait a bit
noTone(piezoPin); // stop the tone
delay(ldrValue); // wait the amount of milliseconds in ldrValue
}
Thermometer
// Project 8 - Thermometer
#define sensorPin 0
float Celsius, Fahrenheit, Kelvin;
int sensorValue;
void setup() {
Serial.begin(9600);
Serial.println("Initialising.....");
}
void loop() {
GetTemp();
Serial.print("Celsius: ");
Serial.println(Celsius);
Serial.print("Fahrenheit: ");
Serial.println(Fahrenheit);
Serial.println();
delay(2000);
}
void GetTemp()
{
sensorValue = analogRead(sensorPin); // read the sensor
Kelvin = (((float(sensorValue) / 1023) * 5) * 100); // convert to Kelvin
Celsius = Kelvin - 273.15; // convert to Celsius
Fahrenheit = (Celsius * 1.8) +32; // convert to Fahrenheit
}
Binary counter using a shift register
// Project 9 - Binary counter using a shift register
int latchPin = 8; //Pin connected to Pin 12 of 74HC595 (Latch)
int clockPin = 12; //Pin connected to Pin 11 of 74HC595 (Clock)
int dataPin = 11; //Pin connected to Pin 14 of 74HC595 (Data)
void setup() {
//set pins to output
pinMode(latchPin, OUTPUT);
pinMode(clockPin, OUTPUT);
pinMode(dataPin, OUTPUT);
}
void loop() {
//count from 0 to 255
for (int i = 0; i < 256; i++) {
//set latchPin low to allow data flow
digitalWrite(latchPin, LOW);
shiftIt(i);
//set latchPin to high to lock and send data
digitalWrite(latchPin, HIGH);
delay(1000);
}
}
void shiftIt(byte dataOut) {
// Shift out 8 bits LSB first, on rising edge of clock
boolean pinState;
digitalWrite(dataPin, LOW); //clear shift register ready for sending data
digitalWrite(clockPin, LOW);
for (int i=0; i<=7; i++) { // for each bit in dataOut send out a bit
digitalWrite(clockPin, LOW); //set clockPin to LOW prior to sending bit
// if the value of DataOut and (logical AND) a bitmask
// are true, set pinState to 1 (HIGH)
if ( dataOut & (1<<i) ) {
pinState = HIGH;
}
else {
pinState = LOW;
}
//sets dataPin to HIGH or LOW depending on pinState
digitalWrite(dataPin, pinState); //send bit out on rising edge of clock
digitalWrite(clockPin, HIGH);
}
digitalWrite(clockPin, LOW); //stop shifting out data
}
LED dot matrix
// Project 10
#include <TimerOne.h>
int latchPin = 8; //Pin connected to Pin 12 of 74HC595 (Latch)
int clockPin = 12; //Pin connected to Pin 11 of 74HC595 (Clock)
int dataPin = 11; //Pin connected to Pin 14 of 74HC595 (Data)
byte led[8]; // 8 element unsigned integer array to store the sprite
void setup() {
pinMode(latchPin, OUTPUT); // set the 3 digital pins to outputs
pinMode(clockPin, OUTPUT);
pinMode(dataPin, OUTPUT);
led[0] = B11111111; // enter the binary representation of the image
led[1] = B10000001; // into the array
led[2] = B10111101;
led[3] = B10100101;
led[4] = B10100101;
led[5] = B10111101;
led[6] = B10000001;
led[7] = B11111111;
// set a timer of length 10000 microseconds (1/100th of a second)
Timer1.initialize(10000);
// attach the screenUpdate function to the interrupt timer
Timer1.attachInterrupt(screenUpdate);
}
void loop() {
for (int i=0; i<8; i++) {
led[i]= ~led[i]; // invert each row of the binary image
}
delay(500);
}
void screenUpdate() { // function to display image
byte row = B10000000; // row 1
for (byte k = 0; k < 9; k++) {
digitalWrite(latchPin, LOW); // open latch ready to receive data
shiftIt(~led[k] ); // shift out the LED array (inverted)
shiftIt(row ); // shift out row binary number
// Close the latch, sending the data in the registers out to the matrix
digitalWrite(latchPin, HIGH);
row = row >> 1; // bitshift right
}
}
void shiftIt(byte dataOut) { // Shift out 8 bits LSB first, on rising edge of clock
boolean pinState;
digitalWrite(dataPin, LOW); //clear shift register read for sending data
for (int i=0; i<8; i++) { // for each bit in dataOut send out a bit
digitalWrite(clockPin, LOW); //set clockPin to LOW prior to sending bit
// if the value of DataOut and (logical AND) a bitmask
// are true, set pinState to 1 (HIGH)
if ( dataOut & (1<<i) ) {
pinState = HIGH;
}
else {
pinState = LOW;
}
//sets dataPin to HIGH or LOW depending on pinState
digitalWrite(dataPin, pinState);
digitalWrite(clockPin, HIGH); //send bit out on rising edge of clock
digitalWrite(dataPin, LOW);
}
digitalWrite(clockPin, LOW); //stop shifting
}
Animated LED dot matrix
// Project 11
#include <TimerOne.h>
int latchPin = 8; //Pin connected to Pin 12 of 74HC595 (Latch)
int clockPin = 12; //Pin connected to Pin 11 of 74HC595 (Clock)
int dataPin = 11; //Pin connected to Pin 14 of 74HC595 (Data)
byte frame = 0; // variable to store the current frame being displayed
byte led[8][8] = { {0, 56, 92, 158, 158, 130, 68, 56}, // 8 frames of an animation
{0, 56, 124, 186, 146, 130, 68, 56},
{0, 56, 116, 242, 242, 130, 68, 56},
{0, 56, 68, 226, 242, 226, 68, 56},
{0, 56, 68, 130, 242, 242, 116, 56},
{0, 56, 68, 130, 146, 186, 124, 56},
{0, 56, 68, 130, 158, 158, 92, 56},
{0, 56, 68, 142, 158, 142, 68, 56} };
void setup() {
pinMode(latchPin, OUTPUT); // set the 3 digital pins to outputs
pinMode(clockPin, OUTPUT);
pinMode(dataPin, OUTPUT);
Timer1.initialize(10000); // set a timer of length 10000 microseconds
Timer1.attachInterrupt(screenUpdate); // attach the screenUpdate function
}
void loop() {
for (int i=0; i<8; i++) { // loop through all 8 frames of the animation
for (int j=0; j<8; j++) { // loop through the 8 rows per frame
led[i][j]= led[i][j] << 1 | led[i][j] >> 7; // bitwise rotation
}
}
frame++; // go to the next frame in the animation
if (frame>7) { frame =0;} // make sure we go back to frame 0 once past 7
delay(100); // wait a bit between frames
}
void screenUpdate() { // function to display image
byte row = B10000000; // row 1
for (byte k = 0; k < 9; k++) {
digitalWrite(latchPin, LOW); // open latch ready to receive data
shiftIt(~led[frame][k] ); // LED array (inverted)
shiftIt(row); // row binary number
// Close the latch, sending the data in the registers out to the matrix
digitalWrite(latchPin, HIGH);
row = row >> 1; // bitshift right
}
}
void shiftIt(byte dataOut) {
// Shift out 8 bits LSB first, on rising edge of clock
boolean pinState;
//clear shift register read for sending data
digitalWrite(dataPin, LOW);
// for each bit in dataOut send out a bit
for (int i=0; i<8; i++) {
//set clockPin to LOW prior to sending bit
digitalWrite(clockPin, LOW);
// if the value of DataOut and (logical AND) a bitmask
// are true, set pinState to 1 (HIGH)
if ( dataOut & (1<<i) ) {
pinState = HIGH;
}
else {
pinState = LOW;
}
//sets dataPin to HIGH or LOW depending on pinState
digitalWrite(dataPin, pinState);
//send bit out on rising edge of clock
digitalWrite(clockPin, HIGH);
digitalWrite(dataPin, LOW);
}
digitalWrite(clockPin, LOW); //stop shifting
}
