no serial output, simple problem ?

Hello forum I'm using a Arduino mini and I programmed it succesfully with the mini USB adapter. So far so good. But I don't succeed in getting the next code exporting the serial data. The led is working. The serial port on the reading-side is also OK, I checked it with connecting another 4800 baud device (GPS). Any good suggestions ? I'm sure it's something small and stupid >:( Thanks very much for your help. Joris Peumans

int ledPin = 13;                // LED connected to digital pin 13

void setup()
  pinMode(ledPin, OUTPUT);      // sets the digital pin as output
  Serial.begin(4800);                     // open serial port

void loop()
  digitalWrite(ledPin, HIGH);   // sets the LED on
  delay(1000);                  // waits for a second
  digitalWrite(ledPin, LOW);    // sets the LED off
  delay(250);                  // waits for a 1/4 second

The code looks fine. What are you using to try to see the serial data coming out? Did you try it in the serial monitor in the Arduino environment?

Hello Mellis Thanks for your fast attention to this topic. I'm connecting directly (rx/tx/ground/5v) to a seperate Linux computer and just reading the serial port.

When I use the serial monitor in the Arduino environment, it works. But in that case the Mini USB Adapter is in between and it's another computer in Windows environment.

So, my goal is: Linux + directly connected Arduino.

Thanks for your opinion. Joris

I read this:

Serial: 0 (RX) and 1 (TX) ... On the Arduino Mini and LilyPad Arduino, they are intended for use with an external TTL serial module (e.g. the Mini-USB Adapter).

I think this is exactly my problem :-/

Thread with same problem:

Right. The serial port in a computer (RS-232) works at -12V and 12V (I think), whereas the output from the Arduino pins 0 and 1 is 0 and 5 volts. So you need something to convert the voltage levels (like a MAX232 chip).