Article ID: 000083775 Content Type: Error Messages Last Reviewed: 12/01/2012

Error Message Citing Different I/O Standards for DQ I/O and DQS I/O Pins

Environment

    Quartus® II Subscription Edition
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Critical Issue

Description

This problem affects DDR2, DDR3, LPDDR2, QDR II, RLDRAM II, and RLDRAM 3 products.

When compiling your memory interface, you might receive warning messages resembling the following:

DQ I/O pins fed by DQS I/O pin "I/O pad mem_dqs[n]" assigned different I/O standards -- it is recommended that all DQ I/O pins fed by the same DQS I/O pin have the same I/O standard

Resolution

If you receive this warning message, check that the DQ I/O pins associated with the warning are set to SSTL-15 CLASS I, and that the DQS pin is set to DIFFERENTIAL 1.5-V SSTL CLASS I. If the pins are set as described, the warning is false and can be ignored.

This issue will be fixed in a future release.

Related Products

This article applies to 1 products

Intel® Programmable Devices

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