Answers Database


2.1i Virtex Map - Virtex mapper treats OBUF driving PU, PD, or KEEPER inconsistently.


Record #7349

Product Family: Software

Product Line: FPGA Implementation

Product Part: map

Product Version: 2.1i

Problem Title:

2.1i Virtex Map - Virtex mapper treats OBUF driving PU, PD, or KEEPER inconsistently.


Problem Description:
The Virtex mapper exhibits inconsistent behavior in dealing with an OBUF (not OBUFT) connected to a PULLUP, PULLDOWN, or KEEPER. Here are the results:

   PULLUP: trims the PULLUP, implementing the IOB with PULL:#OFF
   PULLDOWN: implement the IOB with PULL:PULLDOWN
   KEEPER: issue user fatal error that KEEPER can only be connected to OBUFT, IOBUF, or IBUF

If the OBUF is changed to an OBUFT, all of the above cases work properly.


Solution 1:

This problem is fixed in the latest 2.1i Service Pack available at:
http://support.xilinx.com/support/techsup/sw_updates/




End of Record #7349 - Last Modified: 10/18/99 09:44

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