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AR# 46782

MIG 7 Series DDR2 SDRAM - "Error:MapLib:1121" occurs when KEEP HIERARCHY is set to "YES"


Version Found: V1.4

Version Resolved: Xilinx Answer 45195

All of the MIG 7 Series designs have been tested with the default XST option. 

When "Keep Hierarchy" is set to YES, the following errors will be seen in MAP :

ERROR:MapLib:1121 - ddr2_ctrl_tl_i/mig_ddr2_wrapper_i/mig_ddr2_core_i/u_memc_ui_top_std/mem_intfc0/ddr_phy_top0/u_ddr_mc_phy_wrapper/gen_dqs_iobuf[0].gen_dqs_diff.u_iobuf_dqs/OBUFTDS is driven by ddr2_ctrl_tl_i/mig_ddr2_wrapper_i/mig_ddr2_core_i/u_memc_ui_top_std/mem_intfc 0/ddr_phy_top0/u_ddr_mc_phy_wrapper/u_ddr_mc_phy/ddr_phy_4lanes_0.ddr_phy_4la nes/ddr_byte_lane_B.ddr_byte_lane_B/ddr_byte_group_io/dqs_gen.oddr_dqs (Q pin) and ddr2_ctrl_tl_i/mig_ddr2_wrapper_i/mig_ddr2_core_i/u_memc_ui_top_std/mem_intfc0/ddr_phy_top0/u_ddr_mc_phy_wrapper/u_ddr_mc_phy/ddr_phy_4lanes_0.ddr_phy_4lanes/ddr_byte_lane_B.ddr_byte_lane_B/ddr_byte_group_io/dqs_gen.oddr_dqsts (Q pin),but they are not all in the same level of hierarchy. Please ensure that any OBUF(T)DS with differential IOSTANDARD that is driven by a register or OSERDES exists in the same level of hierarchy as its drivers. This may be achieved by setting KEEP_HIERARCHY=FALSE on those levels of hierarchy separating the OBUF(T)DS from its drivers.



To work around this issue, set "Keep Hierarchy" to Soft or add keep_hierarchy constraints for all of the sub-modules of the MIG design.

This can be done in either the xcf or ucf file. 

For example:

 INST "u_mig_7series_v1_4*" keep_hierarchy= no; The syntax for UCF : INST "u_mig_7series_v1_4*" KEEP_HIERARCHY = FALSE;

Revision History:
08/04/2014 - Initial Release
AR# 46782
Date Created 03/09/2012
Last Updated 08/07/2014
Status Active
Type Known Issues
  • Artix-7
  • Kintex-7
  • Virtex-7
  • ISE Design Suite
  • MIG 7 Series