Unable to upload Program

Hello

I have been using a arduino uno for a while and it worked great until yesterday.

I was able to upload programs on a ubuntu machine then a 64 bit windows machine.

Then i loaded a simple serial program and powered the uno with a 12v dc supply and pluged in the serial/usb line.

I wanted to be able to open a terminal and communicate with the arduino. This failed.

Since then I have been unable to load even the blink program.

I get the following error

avrdude: stk500_getsync(): not in sync: resp=0x00.

I have read a few topics on this and most of the time it looks like a serial port error. But I was working and did not change my serial port settings. I have also tried to hold down the reset then plug in the serial port, release reset then upload a program. That failed.

Can anyone give me any suggestions on how to recover my uno. Just in case I have the very simple code I used before the uno locked up.

Thanks

Aaron

// pins for control

const int pin2 = 2;

const int pin4 = 4;

const int pin7 = 7;

void setup() {

// initialize serial:

Serial.begin(9600);

// make the pins outputs:

pinMode(pin2, OUTPUT);

pinMode(pin4, OUTPUT);

pinMode(pin7, OUTPUT);

}

void loop() {

// if there’s any serial available, read it:

while (Serial.available() > 0) {

// look for the next valid integer in the incoming serial stream:

int oneIn = Serial.parseInt();

// do it again:

int twoIn = Serial.parseInt();

// do it again:

int threeIn = Serial.parseInt();

// look for the newline. That’s the end of your

// sentence:

if (Serial.read() == ‘\n’) {

if(oneIn == 1) {

digitalWrite(pin2,HIGH);

Serial.println(“Pin 2 toggle”);

delay(1000);

digitalWrite(pin2,LOW);

}

if(twoIn == 1) {

digitalWrite(pin4,HIGH);

Serial.println(“Pin 4 toggle”);

delay(1000);

digitalWrite(pin4,LOW); }

if(threeIn == 1) {

digitalWrite(pin7,HIGH);

Serial.println(“Pin 7 toggle”);

delay(1000);

digitalWrite(pin7,LOW); }

}

}

}

Hi:

I have had this error a couple of times and it has most of the time been a port error. Check both the Arduino and the computer port assignments. The computer can assign a different port than the Arduino picks and you’ll get the error. Reasigning both to the same port fixes it.

One time I had a faulty Arduino and it would not load, same error. Check to see that the only power source for the Arduino is from the USB line when you are trying to load. Good luck.

Bela