On the contrary, electronic info on TCAS / ACAS is
plentiful. Take the previous link as an example.
For he sake of simplicity, let's say that the TCAS boxes in two (or more!) aircraft exchange data on position so to calculate trajectory vectors and the point of closest approach and distance at it. If the separation breches certain limits, visual and for some instances aural alerts are presented to pilots. These alerts come at four levels of importance, the highest called "Resolution Advisory" which in fact provides steering cues away from conflicting traffic. Under standard conditions these alerts are co-ordinated among the aircraft involved and observe certain performance boundaries of individual aircraft, also margins for reasonable reaction time and inertia are applied.
Cheers,
FD.