How to make enable realtime shadows and lightmap always in the same time ?

I have problem because a don’t know how to make my ligthmap on my terrain( not unity terrain, but my model) always visible , and always visible realitme shadows for characters in the same time , I try with dual lightmaps but This solution , disable lightmaps when enable realtime shadows.
please help

It is not possible in Unity Free but only in Unity Pro

But these work in Unity Free : Here and Here

I have unity pro , and I have this problem , problem is that I want have always enable lightmap not only in far , and always enable reltime shadows for characters , all in the same time