Multiple selection screen

Hi,

I have two selection screens. one is thedefault screen which contains two radio

buttons r1,r2.Other screeen say '200' is having SELECT-OPTIONS and

PARAMETERS which has to be validated using another program when we enter

values.If I select radio button one it should call the screen 200.If I select radio button

it should call one function.I am getting dump "you requested too many consecutive

nested call screens".what i have to do avoid this dump?

I have reffered the related link of same kind of question .But i dont get the point.

Regards,

Mythili