Help with events from Host to Flash

Hello All,
Being a newbie in flash I am not very good at it. This may be a trivial question but here it goes.

I have a small application for flash lite 2.0. I need to display an image on the screen whenever the host application wants it. I know I can use fscommands to communicate with the host …but how can a host send events to the flash…any way for this one…

Please help//