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AR# 29549

Spartan-3E/-3A/-3AN - "ERROR:PhysDesignRules:792 when using the DCM with Variable Phase Shift in High Frequency Mode"

Description

What is the cause of:

"ERROR ERROR:PhysDesignRules:792 - Illegal configuration for block XX/YDcm. The

cell < DCM> has the following precondition programming

<DLL_FREQUENCY_MODE>:<HIGH>. The cell < DCM>, has the following

precondition mode <CLKOUT_PHASE_SHIFT> defined as being used. The cell

< DCM>, must have the following programming <CLKOUT_PHASE_SHIFT>:<NONE>.

ERROR:Pack:1642 - Errors in physical DRC."

When using the DCM with Variable Phase Shift in High Frequency Mode in ISE 9.2.03 for Spartan-3E/-3A/-3AN?

Solution

This is an invalid error in MAP as it is possible to have variable phase shift in high-frequency mode in Spartan-3E/-3A/-3AN DCMs. In order to work around this issue, set the frequency mode to Low. The DCM will still function correctly in hardware as the Spartan-3E/-3A/-3AN DCMs have automatic frequency sensing.

This issue will be fixed in a later release of software.

AR# 29549
Date Created 05/08/2008
Last Updated 12/15/2012
Status Active
Type General Article