Internal Error: Sub-system: FTITAN, File: /quartus/fitter/ftitan/ftitan_expert.cpp, Line: 4431

Description

Due to a problem in the Quartus® II software version 13.1 and earlier, you may see this error in designs that implement the altlvds_rx megafunction with the Use External PLL option enabled.

Resolution

To work around this problem, in your design implement and open a PLL megafunction. For the output clock that drives the rx_inclock of the altlvds_rx megafunction, enable the option Use these clock settings for the DPA clock.

This problem is scheduled to be fixed in a future release of the Quartus II software.