a quick and dirty example, but I think you get the point..
Graphics 800,600,0 'set gfx mode Global a:String = "test text" Global time:Int = MilliSecs() Repeat check() Cls DrawText a,250,0 Flip FlushMem Until KeyHit(KEY_ESCAPE) Function check() If MilliSecs() - time > 1000 a = "HEY!" EndIf EndFunction