question about altgx simulation

Hello,

I'm working on the transceivers of a Stratix IV GX230 FPGA in basic mode.

In the megawizard, I'm using the following settings:

-Protocol : Basic

-Subprotocol: None

-operation mode: Receiver and Transmitter

-Number of Channel : 1

-deserializer block width: Single

-Channel Width: 8

-Input clock : 160MHz

-Data rate :1600Mbps

-8b/10b mode : normal

I transmit the control data K28.5(0xBC) continuously.

The problem is the signal "tx_dataout" is unknown but not serialization data in simulation wave.

Attachments is my simulation wave.

regards