Arduino crashes when sending bytes from Java [on hold]
- by francisaugusto
I used the sample program from the arduino website in order to send and receive data via serial to my Arduino one. However, for some reason, even when I try to send only one byte, the Arduino crashes after a while. It doesn't happen if I send the chars manually via the IDE's own serial monitor.
I wrote the following method to output the character to Arduino:
public synchronized void serialWrite(char sendIt){
try {
output.write((byte)'0');
output.flush();
for (int j=0;j<1000000000;j++){
}
}catch (Exception e){System.out.println("Not connected...");}
notify();
}
What I try above is to send just one character when the method is called. I send just a '0' char for testing. After manually calling the method two or three times, Arduino crashes.
Is there anything I should be looking into?
The Arduino code:
#include <SoftwareSerial.h>
int buttonState=0;
int lastButtonState=0;
int buttonPushCounter=0;
long previousMillis=0;
long interval=250;
int ledState=LOW;
int ledState2=LOW;
int ledState3=LOW;
long timeElapsed=0;
SoftwareSerial portOne(10,11);
void setup(){
pinMode(3,OUTPUT);
pinMode(4,OUTPUT);
pinMode(5,OUTPUT);
pinMode(2,INPUT);
Serial.begin(9600);
portOne.begin(9600);
}
boolean turnoff;
void loop(){
if(portOne.overflow()){
Serial.println("There's an overflow here!");
}
buttonState= digitalRead(2);
if(buttonState!=lastButtonState){
if (buttonState==HIGH){
buttonPushCounter++;
}
}
lastButtonState=buttonState;
if (turnoff){
unsigned long currentMillis=millis();
if (currentMillis-previousMillis>0 && currentMillis-previousMillis<interval){
ledState=HIGH;
ledState2=LOW;
ledState3=LOW;
}else
if (currentMillis-previousMillis>interval && currentMillis-previousMillis<interval*2){
ledState=LOW;
ledState2=LOW;
ledState3=HIGH;
}else
if (currentMillis-previousMillis>interval*2 && currentMillis-previousMillis<interval*3){
ledState=LOW;
ledState2=HIGH;
ledState3=LOW;
}else if (currentMillis-previousMillis>interval*3){
previousMillis=currentMillis;
}
digitalWrite(3,ledState);
digitalWrite(4,ledState2);
digitalWrite(5,ledState3);
}else{
digitalWrite(3,LOW);
digitalWrite(4,LOW);
digitalWrite(5,LOW);
}
if (buttonPushCounter==1){
Serial.print("Button pressed!\n");
turnoff=!turnoff;
buttonPushCounter=0;
}
noInterrupts();
char ch=Serial.read();
delay(1);
if(ch=='0'){
Serial.println("Changed by serial"+turnoff);
Serial.println(ch);
turnoff=!turnoff;
}
interrupts();
}