// Maurice Ribble // 4-6-2008 // http://www.glacialwanderer.com/hobbyrobotics // This code just lets you turn a digital out pin on and off. That's // all that is needed to verify a relay curcuit is working. // Press the space bar to toggle the relay on and off. #define RELAY_PIN 3 void setup() { pinMode(RELAY_PIN, OUTPUT); Serial.begin(9600); // open serial Serial.println("Press the spacebar to toggle relay on/off"); } void loop() { static int relayVal = 0; int cmd; while (Serial.available() > 0) { cmd = Serial.read(); switch (cmd) { case ' ': { relayVal ^= 1; // xor current value with 1 (causes value to toggle) if (relayVal) Serial.println("Relay on"); else Serial.println("Relay off"); break; } default: { Serial.println("Press the spacebar to toggle relay on/off"); } } if (relayVal) digitalWrite(RELAY_PIN, HIGH); else digitalWrite(RELAY_PIN, LOW); } }