Read UID with Arduino Micro board and Sonmicro reader

Good Evening

I am almost completly new to arduino. All i've ever done with it was making led's blink. So, I'm kinda desperate right now, i have around 19 hours to finish this project i just got assinged with.

Basically i have to read from an Sonmicro 2300 RFID reader (yes this exists, it's written on the reader itself but i cant find it by googling) the UID from a tag with my Arduino micro. The reader is correctly wired to the RX-Pin (which should be pin 4, but im not sure). The whole question is basically, how can i read from the RX-pin, which i believe is pin4. I dont have more information myself so i would be glad for any hint. A simple example of reading something from this pin would be great, i wont understand the complicated ones anyway...

Hopefull regards Nodua

Finally it works.

I feel kinda stupid it was so simple, I just had to use Serial1 to read from the TX pin:

char inData[15]; // Allocate some space for the string
char inChar; // Where to store the character read
byte index = 0; // Index into array; where to store the character

void setup()
void loop()
while(Serial1.available() > 0){
     if(index < 14) // One less than the size of the array
           inChar =; // Read a character
           if(index > 6)
             inData[index - 7] = inChar; // Store it
           index++; // Increment where to write next
           inData[index] = '\0'; // Null terminate the string

It’s not pretty but it works.