Hey,

I'm trying to get my arduino (link) sent data to processing which logs the data. I do this because arduino can't log the data itself. The data that is sent has a resolution of 10bits, so I use an integer (16bits). I divide this integer into two bytes because of the protocol. Processing has to paste these two bytes to eachother to give me my correct data.

The problem I have in these programs is that processing creates a file, but it stays empty. I allready checked that arduino is sending data to processing so I think the problem is in processing. Does anybody see the problem?

ArduinoProgram:

1. int sensePin=0;
2. int x;
3. unsigned long current_time;
4. unsigned long previous_time;
5. int time_stamp;
6. void setup()
7. {
8.   Serial.begin(115200);
9.   previous_time = micros();
10. }
11. void loop()
12. {
13.   x=analogRead(sensePin);
14.   current_time = micros();
15.   time_stamp = int(current_time - previous_time);
16. //  while(time_stamp<500) {
17. //    current_time = micros();
18. //    time_stamp = int(current_time - previous_time);
19. //  }
20.   previous_time = current_time;
21.   Serial.write(255);
22.   Serial.write(lowByte(x));
23.   Serial.write(highByte(x));
24.   Serial.write(lowByte(time_stamp));
25.   Serial.write(highByte(time_stamp));
26. }

ProcessingProgram:

1. import processing.serial.*;
2. import java.util.Date;
3. Serial myPort;
4. FileWriter file;
5. String filename;
6. void setup()
7. {
8.  
9.   myPort = new Serial(this, "COM4", 115200);
10.   long thisDate = new Date().getTime();
11.   filename =  "output-" + thisDate + ".txt";
12.   
13.   try {
14.        String emptyStart = "";
15.        file = new FileWriter(filename, false); // Wtrite empty string to file to clear it on start
16.        file.write(emptyStart, 0, emptyStart.length()); //(string, start char, end char)
17.        //file.close();
18.      } 
19.        catch(Exception e) 
20.      { 
21.        println("Error: Can't open file!");
22.      }
23.   }
24. void draw()
25. {
26.   readSerial();
27. }
28. void readSerial()
29. {
30.   println(myPort.available());
31.   if (myPort.available() > 5) {
32.     int serial_in = myPort.read(); // read a byte from the Serial Port
33.     while (serial_in != 255) {
34.       serial_in = myPort.read(); // read until value 255 is read
35.     }
36.     int lowByte = myPort.read();
37.     int highByte = myPort.read();
38.     int sample = highByte * 256 + lowByte;
39.     lowByte = myPort.read();
40.     highByte = myPort.read();
41.     int timestamp = highByte * 256 + lowByte;
42.     myPort.clear();
43.   }
44. }
45.  
46.     void keyPressed(){
47.       if ( key == 's' ){
48.          try {
49.            file.close();
50.          } catch (IOException e) {
51.            System.err.println(e);
52.          }
53.          exit();
54.       }
55.     }

Thanks a lot for helping me,
It's about my first experience with this stuff

Hello,

I'm trying to make a program which logs the data received at my com-port. You probably also know the arduino-boards, I attached a sensor to this board and made a connection with my pc. The program I load on my arduino works, but the one on processing gives an error and I can't find the problem.

The error is: unhandled exception type IOException. I searched the internet and I saw a couple of posts on this topic. But they all say I have to add "throw IOEception" in the line. This doesn't work, so I was wondering if someone on this forum might know the solution.

1. import processing.serial.*;
2. import java.util.Date;
3. Serial myPort;
4. FileWriter file;
5. String filename;
6. void setup()
7. {
8.   myPort = new Serial(this, "COM4", 115200);
9.   long thisDate = new Date().getTime();
10.   filename =  "output-" + thisDate + ".txt";
11.     try {
12.        String emptyStart = "";
13.        file = new FileWriter(filename, false); // Wtrite empty string to file to clear it on start
14.        file.write(emptyStart, 0, emptyStart.length()); //(string, start char, end char)
15.        //file.close();
16.      } 
17.        catch(Exception e) 
18.      { 
19.        println("Error: Can't open file!");
20.      }
21.   }
22. void draw()
23. {
24.   readSerial();
25. }
26. void readSerial()
27. {
28.   println(myPort.available());
29.   if (myPort.available() > 5) {
30.     int serial_in = myPort.read(); // read a byte from the Serial Port
31.     while (serial_in != 255) {
32.       serial_in = myPort.read(); // read until value 255 is read
33.     }
34.     int lowByte = myPort.read();
35.     int highByte = myPort.read();
36.     int sample = highByte * 256 + lowByte;
37.     lowByte = myPort.read();
38.     highByte = myPort.read();
39.     int timestamp = highByte * 256 + lowByte;
40.     myPort.clear();
41.   }
42. }
43. void keyPressed(){
44.  
45.   if ( key == 's' ){
46.      file.close();
47.      exit();
48.   }
49. }

I hope you guys can help me, Thanks