Arduino Nano TX LED is on My Arduino nano make weired thing... 
The TX LED is on when i define a Variable and a digital Pin as output. Do you now if it is a error in the code? If I upload a clear new sketch the LED is off.

~Nico

Code:


int ok = 1;
int err = 0;
int x1 = 2;
int x2 = 3;
int x3 = 4;
int x4 = 5;
int x5 = 6;
int x6 = 7;
int y1 = 8;
int y2 = 9;
int y3 = 10;
int y4 = 11;
int y5 = 12;
int y6 = 13;
int value1 = digitalRead(14);
int value2 = digitalRead(15);
int value3 = digitalRead(16);
int test = digitalRead(17);

void setup() {
  pinMode(0, OUTPUT);
  pinMode(1, OUTPUT);
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(7, OUTPUT);
  pinMode(8, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(10, OUTPUT);
  pinMode(11, OUTPUT);
  pinMode(12, OUTPUT);
  pinMode(13, OUTPUT);
  pinMode(14, INPUT);
  pinMode(15, INPUT);
  pinMode(16, INPUT);
  pinMode(17, INPUT);
}

void loop() {
  // put your main code here, to run repeatedly:

}
You configure serial pins as output, this may be your issue.



also, you're calling some digitalRead() before setup call, you would have to do that in the loop.