Serial data to computer.

I have an issue with reading data from controller. Symbols not the same like they coded in controller. May be this is have something with UTF-8 ? I'm running linuxbox for development. According to examples

void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
}

// the loop routine runs over and over again forever:
void loop() {
  Serial.write('Hello Arduino');
  Serial.flush();
  delay(1000);        // delay in between reads for stability
}

But I have only 'o' in serial monitor

  Serial.write('Hello Arduino');

Single quotes are for single characters. Which ONE key did you press to get that ONE character?

I press nothing just open serial monitor, also with double quotes no data at all.

also with double quotes no data at all.

You should spend some time on the reference page, then. In particular, look at the difference between Serial.print() and Serial.write(). Try to determine which makes more sense for sending ASCII data.

Pay some real attention to what Serial.flush() actually does, and explain why you think you need to call it.

Your code works for me if I change the single quotes to double quotes.

Serial.write("Hello Arduino");

Serial.println() would be more appropriate.
Serial.flush is unnecessary.

...R