Arduino Uno and Ciseco Erf

Hello!

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.

Greets
mazi

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http://ciseco.co.uk/downloads/documents/datasheet%20-%20XRF%20v1-6.pdf

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

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