With the Twitter library for Arduino from the Arduino Playground you can make it post a message to Twitter.
First, follow this link to get a token to post a message using OAuth and to add some Libraries to your Arduino IDE. Then test it with this sketch:
#include// needed in Arduino 0019 or later #include #include char ssid[] = ""; // Your WiFi network name char pass[] = ""; // Your WiFi network password // Your Token to Tweet (get it from http://arduino-tweet.appspot.com/) Twitter twitter(""); // Message to post char msg[] = "Hello world! This is your #Arduino tweeting!"; void setup() { delay(1000); WiFi.begin(ssid, pass); Serial.begin(9600); int status = -1; while (status != 200) { Serial.print("Message: "); Serial.println(msg); Serial.println("Connecting to Twitter..."); if (twitter.post(msg)) { status = twitter.wait(&Serial); if (status == 200) { Serial.println("OK."); } else { Serial.print("Failed : code "); Serial.println(status); waitToContinue(30); } } else { Serial.println("Connection failed."); } } } void waitToContinue(int duration) { int step = 5; for(int i = duration; i>0; i-=step) { Serial.print("Waiting "); Serial.print(i); Serial.println(" seconds..."); delay(step*1000); } } void loop() { }
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