CRS IN how does it work?

[c0sm0cat]

The DIR page of the A400M has also options like CRS IN and CRS OUT besides the normal direct-to. But how does it work? Where do I set the course that I want to fly to the point I enter there? If I select CRS IN and enter a wypoint, the A400M behaves exactly the same way as if I'd chosen the normal direct-to function. Where do I set the radial I want to fly to that waypoint?