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AR# 35439

Xilinx Implementation Tool Solution Center - PACK Section of Design Assistant


Please refer to the following to learn more about the PACK section of the Xilinx Implementation Tools or to find help on debugging an issue you are currently encountering.

NOTE: This Answer Record is a part of the Design Assistant section (Xilinx Answer 34756) of theXilinx Implementation Tool Solution Center (Xilinx Answer 34752) The Xilinx Implementation Solution Center is available to address questions related to Xilinx Implementation Tools.


Explanation of PACK tool functions:

See (Xilinx Answer 35507) for information on using IOB constraints to control packing of FFs into IOB or OLOGIC components.
See (Xilinx Answer 35508) for information on using LOCK_PINS constraint to prevent optimization of LUTs used as delay elements.
See (Xilinx Answer 35509) for information on how to control Slice packing with RLOC, BEL, BLKNM, XBLKNM constraints.

Debugging Tips for PACK Issues:

See (Xilinx Answer 29711) for information on debugging Directed Packing errors, Pack:679 and Pack:2811
See (Xilinx Answer 25058) for information on debuggingIO Packing errors, Pack:1107
See (Xilinx Answer 23165) for information on debuggingtiming impossible errors, Pack:1653
See (Xilinx Answer 35520) for information on debugging IO register packing issues.

High Frequency PACK Issues:

See (Xilinx Answer 34120) for information in getting Inverters to get pushed into IOB FF input inversion muxes.
See (Xilinx Answer 34993) for information on Pack errors caused by IOSTANDARD issues.
See (Xilinx Answer 31145) for Pack:2310 errors.
See (Xilinx Answer 33740) change in IODELAY insertion behavior with ISE 11.3.

Latest PACK Issues:

See (Xilinx Answer 34120) for information in getting Inverters to get pushed into IOB FF input inversion muxes.

Linked Answer Records

Associated Answer Records

Answer Number Answer Title Version Found Version Resolved
34752 Xilinx Implementation Tools Solution Center N/A N/A
34756 Xilinx Implementation Tools Solution Center - Design Assistant N/A N/A
AR# 35439
Date 12/15/2012
Status Active
Type General Article
  • Spartan-3
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  • Spartan-3AN
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