Arduino Uno and Ciseco Erf


I have 2 Arduino Uno and 2 Ciseco Erf.
One Arduino and one Erf should send text and the other Arduino+Erf should recieve the text and write it into the Arduino Serial Monitor.

Now I have some Questions:

  1. To which pin on the Arduino should i connect the RX pin from the Erf? (Same for the TX pin at the other side)
  2. How can i send text from the Arduino?

Hope you can help me.



Thats ciseco Erf, because they dont have a datasheet for ERF.
But that one is very similar