Digi outputs 1 2 3 are preconfigured for (1) fire (2) PA (3) Intruder as these are standard across most speach diallers. you can re assign the to hundreds of different options if you want to reconfigure them
there are a lot of standard options with each system that texecom think is a good default option.
They are also programmed active high so you will need to use option [4] on the informer to alter input levels to active high.