Due to a problem in the Quartus® II software version 12.1 SP1, you may see the above internal error during compilation for designs containing external memory interface IP that target Cyclone® V devices.
A patch is available to fix this problem for the Quartus II software version 12.1SP1. First, download and install patch 1.dp6 from the related solution below. After installing patch 1.dp6, download and install patch 1.dp6k from the appropriate links below:
- Download the version 12.1 SP1 patch 1.dp6k for Windows (.exe)
- Download the version 12.1 SP1 patch 1.dp6k for Linux (.tar)
- Download the Readme for the Quartus II software version 12.1 SP1 patch 1.dp6k (.txt)
This problem is scheduled to be fixed in a future release of the Quartus II software.