What does this button do?

[Swarren529]

I know this may be a stupid question but I just can’t figure out what this button does.  Thanks in advance to anyone who could enlighten me about it !

 

 

[Coop]

That is the GCU 479 which is in later model Cirrus aircraft with the Perspective+ avionics (G5, G6). We model the G3 series which has the GCU 478 with Perspective avionics. The Home key on the GCU 479 displays the navigation map page, returning to there from any other view you may have previously been in.

[Swarren529]

Thanks Coop!!!  Love this airplane!