Reed Slomon IP decoder

hello everyone:

I use reed-solomon IPcore as a decoder

I don't know what should I put as input in the ''bypass signal'' of the decoder which is an input signal for the decoder

I have read the Reed-Solomon Compiler user Guide ,but still a litte confused. I just want to use the R-S IP correctely.please give me some directions, specially that all my decoder output are ''zero'' :( :( :( thank you.

My encoder IP works perfectly.