Implementation

[printcap]

I am trying to implement a quite large design for a XC6LX760. During map I get the following warnings:

Warning: No plconn found for a valid twconn

Warning: No plconn found for a valid twconn

Warning: No plconn found for a valid twconn

Warning: No plconn found for a valid twconn

Warning: No plconn found for a valid twconn

... (repeated a couple of times) ...

The process continues and seems to finish successfully. PAR later on however fails to route all signals. I wonder whether this is related to the map warnings somehow. I am using map Release 11.4 - Map L.68 (lin64).

Does anybody know the meaning of these warnings?  

[timo.pfau]

I get the same warning message (using ISE 12.3). Did somebody find out what caused this problem.

Thanks in advance for your help.

[yzhang]

Please try to turn "register duplication" off.

[zigdapig]

I'm having the same issue, and I cannot believe that the only answer Xilinx is giving, is :

   
            "Please try to turn "register duplication" off. "

What if I DO want to have register duplication ?  Do I need to hand-code this ??

[bwade]

As far as I can tell it is a harmless message. I do not believe that it is necessary to either turn off register duplication or hand-code the design.