I am trying to simulate the IP of SDI receiver with ModelSim. The SDI receiver successfully detects the video standard (rx_std is 2'b10 (HD)) but cannot be alignment and TRS locked (rx_status[4:0] is 5'b00000). The test input video (1920*1080 60i) is generated by a test pattern generator from VIP and transmitted by a SDI transmitter. My testbench simply connects the video output from SDI transmitter to the SDI receiver. I've already checked the sample program provided by Altera in the installed IP directory (C:\altera\11.1\ip\altera\sdi\example\a2gx_tr) and use exactly the same DPRIO for SDI receiver reconfiguration. About the attached files, "MySimuation.jpg" is my simulation result, "SampleSimulation.jpg" is the simulation result of the sample program, and "sdi_tx.v" is my program. Could anyone help me with this problem? Thanks.