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Altera_Forum
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18 years ago

Quartus II Cyclone III DDR Memory problem

I am trying to use 32 MB DDR SDRAM in Cyclone III EP3C25F324C8. But when i compile the project, it gives me error saying The DQ group with DQS pin "mem_dqs_to_and_from_the_memddr[0]" has invali...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
18 years ago

Your DQ pin name looks like you are using SOPC Builder. Even when it is run through SOPC Builder, I think the DDR MegaCore MegaWizard generates a .tcl file with constraints for things like I/O standards. Make sure you've run that script or manually made the same assignments.

The MegaCore user guide might have instructions for running the script. You can get to the user guide through a button in the MegaCore MegaWizard GUI.

Also notice what is in the MegaCore MegaWizard dialog box when MegaCore generation completes. It will list some things you need to do that are not covered by the script.