Hello everybody,

I have a communication problem between Arduino 1.5.2 and Processing 2.0b8. Indeed, when I want to create a new Serial in Processing, i have an error message "Error inside Serial.<init>()". I have already check communication port and everything is ok. Arduino sends the good data because I can see it in the monitoring activity in Arduino but not in Processing. My librairies Java and Native are correct. I'm working on a mac and my installation is working but when I switch with a PC, is not working anymore. Let me show you my code:

Arduino code :

1. #include <DHT22.h>
2. 
   
3. #define DHT22_PIN 7
4. DHT22 myDHT22(DHT22_PIN);
5. 
   
6. const int buttonPin = 2;     //pushbutton pin
7. const int ledPin =  13;      //LED pin
8. 
   
9. // variables
10. int buttonState = 0;         //pushbutton status
11. float temperature = 0;
12. float humidite = 0;
13. String envoie;
14. String but;
15. static char temp[6];
16. static char hum[6];
17. 
    
18. void setup() {
19.   Serial.begin(9600);  
20. 
    
21.   pinMode(ledPin, OUTPUT);      
22.   pinMode(buttonPin, INPUT);
23.   //delay(100);  
24. }
25. 
    
26. void loop(){
27.   // read the state of the pushbutton value:
28.   buttonState = digitalRead(buttonPin);
29. 
    
30.   // check if the pushbutton is pressed.
31.   // if it is, the buttonState is HIGH:
32.   if (buttonState == HIGH) {     
33.     // turn LED on:    
34.     digitalWrite(ledPin, HIGH);
35.     //Serial.println("ok");
36.   } 
37.   else {
38.     // turn LED off:
39.     digitalWrite(ledPin, LOW);
40.     //Serial.println("nok");
41.   }
42. 
    
43.   DHT22_ERROR_t errorCode;
44.   errorCode = myDHT22.readData();
45. 
    
46.   temperature = myDHT22.getTemperatureC();
47.   humidite = myDHT22.getHumidity();
48. 
    
49.   //Serial.print(temperature);
50.   //Serial.print(humidite);
51.   
52.   but = String(buttonState);
53.   dtostrf(temperature, 2, 1, temp);
54.   dtostrf(humidite, 2, 1, hum);
55.   
56.   envoie = String(but+ "," +temp+ "," +hum);
57. 
    
58.   //Serial.print(buttonState+ "," +temperature+ "," +humidite);
59.   Serial.println(envoie);
60. 
    
61.   delay(2000);
62. }

Arduino response :

0,24.9,99.9

0,24.6,99.9

0,24.6,99.9

0,24.7,99.9

0,24.8,99.9

0,24.8,99.9

0,24.9,99.9

0,24.9,99.9

0,24.8,99.9

0,24.6,99.9

Processing response :

Stable Library

=========================================

Native lib Version = RXTX-2.1-7

Java lib Version   = RXTX-2.1-7

[0] "COM3"

gnu.io.PortInUseException: Unknown Application

at gnu.io.CommPortIdentifier.open(CommPortIdentifier.java:354)

at processing.serial.Serial.<init>(Serial.java:178)

at processing.serial.Serial.<init>(Serial.java:116)

at sketch__01P.setup(sketch__01P.java:31)

at processing.core.PApplet.handleDraw(PApplet.java:2241)

at processing.core.PGraphicsJava2D.requestDraw(PGraphicsJava2D.java:243)

at processing.core.PApplet.run(PApplet.java:2140)

at java.lang.Thread.run(Thread.java:662)

Exception in thread "Animation Thread" java.lang.RuntimeException: Error inside Serial.<init>()

at processing.serial.Serial.errorMessage(Serial.java:666)

at processing.serial.Serial.<init>(Serial.java:190)

at processing.serial.Serial.<init>(Serial.java:116)

at sketch__01P.setup(sketch__01P.java:31)

at processing.core.PApplet.handleDraw(PApplet.java:2241)

at processing.core.PGraphicsJava2D.requestDraw(PGraphicsJava2D.java:243)

at processing.core.PApplet.run(PApplet.java:2140)

at java.lang.Thread.run(Thread.java:662)

Hope you can help me :) Thank you for those one who have the solution !