/* Arduino Starter Kit example Project 11 - Crystal Ball This sketch is written to accompany Project 11 in the Arduino Starter Kit Parts required: 220 ohm resistor 10 kilohm resistor 10 kilohm potentiometer 16x2 LCD screen tilt switch Created 13 September 2012 by Scott Fitzgerald http://www.arduino.cc/starterKit This example code is part of the public domain */ // include the library code: #include // initialize the library with the numbers of the interface pins LiquidCrystal lcd(12, 11, 5, 4, 3, 2); // set up a constant for the tilt switchPin const int switchPin = 6; // variable to hold the value of the switchPin int switchState = 0; // variable to hold previous value of the switchpin int prevSwitchState = 0; // a variable to choose which reply from the crystal ball int reply; void setup() { // set up the number of columns and rows on the LCD lcd.begin(16, 2); // set up the switch pin as an input pinMode(switchPin, INPUT); // Print a message to the LCD. lcd.print("Ask the"); // set the cursor to column 0, line 1 // line 1 is the second row, since counting begins with 0 lcd.setCursor(0, 1); // print to the second line lcd.print("Crystal Ball!"); } void loop() { // check the status of the switch switchState = digitalRead(switchPin); // compare the switchState to its previous state if (switchState != prevSwitchState) { // if the state has changed from HIGH to LOW // you know that the ball has been tilted from // one direction to the other if (switchState == LOW) { // randomly chose a reply reply = random(8); // clean up the screen before printing a new reply lcd.clear(); // set the cursor to column 0, line 0 lcd.setCursor(0, 0); // print some text lcd.print("the ball says:"); // move the cursor to the second line lcd.setCursor(0, 1); // choose a saying to print baed on the value in reply switch (reply) { case 0: lcd.print("Yes"); break; case 1: lcd.print("Most likely"); break; case 2: lcd.print("Certainly"); break; case 3: lcd.print("Outlook good"); break; case 4: lcd.print("Unsure"); break; case 5: lcd.print("Ask again"); break; case 6: lcd.print("Doubtful"); break; case 7: lcd.print("No"); break; } } } // save the current switch state as the last state prevSwitchState = switchState; }