Hi,
I'm trying to build a arduino that twitters if my tomatoes need watering, just like botanicalls. So far I was able to send a single twitter, but after that one twitter has been send I keep getting "connection failed"errors. If I want to send another twitter I need to reset the board.
Any hints/ideas are very appreciated 
This is the Code
#include <Ethernet.h>
#include <PString.h>
int moistureSensor1 = 0;
int moisture_val1;
int Relais1 = 8;
//////////// EINSTELUNGEN ///////////////////
// Etherneteinstellungen für das Arduino Board //
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
byte ip[] = { 192, 168, 178, 5 };
byte gateway[] = { 192, 168, 178, 1 };
byte subnet[] = { 255, 255, 255, 0 };
// Twitter Settings //
byte server[] = { 168, 143, 171, 180 }; // IP von Twitter (default: 128.121.146.100)
#define TWITTERURL "/statuses/update.xml" // URL zum Update Script
#define TWITTERUSERNAMEPW "dG9tYXRlbnBxxxxxxxxxxxxxxxxxxxxx" // Base64 enkodet USERNAME:PASSWORT
Client client(server, 80);
char buffer[141];
PString mystring(buffer, sizeof(buffer));
void setup()
{
Ethernet.begin(mac, ip, gateway, subnet); // Ethernet initalisieren
pinMode(Relais1, OUTPUT);
Serial.begin(9600); // Serielle Verbindung für Statusmeldungen
delay(1000); // Kurz warten, um serielle Verbindung zu starten
}
void loop()
{
moisture_val1=analogRead(moistureSensor1);
Serial.println(moisture_val1);
delay(1000);
mystring.print("Actual resistance = "); // start building tweet
mystring.print(moisture_val1);
Serial.println(buffer);
sendTwitterUpdate(buffer);
fetchTwitterUpdate();
}
/// Functions ////
void sendTwitterUpdate(char* tweet) // Nachricht an Twitter übermitteln
{
Serial.println("connecting...");
if (client.connect()) {
Serial.println("connected");
client.print("POST ");
client.print(TWITTERURL);
client.println(" HTTP/1.1");
client.println("Host: twitter.com");
client.print("Authorization: Basic ");
client.println(TWITTERUSERNAMEPW);
client.print("Content-Length: ");
client.println(9+strlen(tweet));
client.println("");
client.println("status=");
client.println(tweet);
Serial.println("twitter message send");
} else {
Serial.println("connection failed");
}
}
void fetchTwitterUpdate() // Rückmeldung von Twitter auslesen
{
if (client.available()) {
char c = client.read();
Serial.print(c);
}
if (!client.connected()) {
Serial.println();
Serial.println("disconnecting.");
client.stop();
}
}