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AR# 11076

11.1 NGDBuild - "ERROR:NgdBuild:466 - %s pad net '%s' has illegal connection Xvendor=%s Xleid=%d Xhiername=%s"


The following error occurs in NGDBuild:

"ERROR:NgdBuild:466 - %s pad net '%s' has illegal connection Xvendor=%s Xleid=%d Xhiername=%s"


If you instantiated an IFD or OFD component and the corresponding IBUF or OBUF components, the IFD and OFD components already contain the IBUF or OBUF components.

The IFD and OFD components are macros that contain an IOB buffer and an FD with an IOB=TRUE attribute. Since there is only one buffer in each direction for a particular IOB, the tools cannot push the register into the IOB.

Use an FD with an IOB=TRUE attribute attached to it instead.


If you instantiated a CORE-Generated component from the Architecture Wizard, this error occurs because the DCM Architecture Wizard is automatically instantiating an IBUFG with the DCM. When this DCM is then used in a top-level design, an IBUF will drive an IBUFG, causing problems that trigger the error.

To work around this issue:

1. Remove the ".xaw" file from the project.

2. Add the "<dcm>.vhd" file to the project.

3. Edit the lines in the ".vhd" file and comment out all the lines of the IBUFG.

AR# 11076
Date Created 08/29/2007
Last Updated 12/15/2012
Status Active
Type General Article