Internal Error: Sub-system: ASMIO, File: /quartus/comp/asmio/asmio_reg.cpp, Line: 2388

Description

Due to a problem in the Quartus® II software version 13.0 and earlier, you may see an internal error with line number 2388, 2390, or 2391 if you have an output enable on a differential output. This configuration is not valid in Altera® devices, but Stratix® V, Arria® V, and Cyclone® V devices do not include this legality check.

Resolution

To work around this issue, do not use an output enable on a differential output.

Future releases of the Quartus II software are scheduled give an error message for this incorrect implementation.