Forum Discussion
Altera_Forum
Honored Contributor
17 years agolooks like problems in the sdc file associated with the DDR memory.
try looking at the Quartus release notes: http://www.altera.com/literature/rn/rn_qts.pdf search for the following line: "The SDC and Tcl scripts generated in Quartus II software versions". you should just need to regenerate the DDR cores in Quartus 8.1.