I'm trying to build a GUI that sends the data from processing to arduino via serial. With the help of a couple of guys on here, I have come up with a basic framework that sends a variable ID, variable value and termination character (\n). So far so good!

However, the [arduino reference][1] advises to only use char for storing characters. How would I send a byte or int over serial, while still being able to use a termination character to ensure everything is working as expected?

edit: Using the arduino code from Edgar's answer below and the following processing code, I get the "could not parse value" error.

import processing.serial.*;

SerialConnection serialConnection;

boolean data_processed = false;
char[] var_array = new char[31];
char var_id;
char var_val;
char space = ' ';
char termchar = '\n';

void setup() {
  serialConnection = new SerialConnection(this, 9600);
}

void draw() {
  serialConnection.startSerialCommunication();

  if (serialConnection.isReady) {
    var_id = 'a';
    var_val = 127;
    serialConnection.serialPort.write(var_id);
    serialConnection.serialPort.write(space);
    serialConnection.serialPort.write(var_val);
    serialConnection.serialPort.write(termchar);

    delay(50);
    while (serialConnection.serialPort.available() > 0) {
      for (int i = 0; i < 30; i++) {
        char inchar = serialConnection.serialPort.readChar();
        var_array[i] = inchar;
        print(var_array[i]);
      }
    }
  }
}