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AR# 53299

MIG 7 Series - MIG fails during synthesis if System Clock = No Buffer and Reference Clock = Use System Clock


Version Found: v1.7
Version Resolved: See (Xilinx Answer 45195)

Designs generated using MIG 7 Series with the settings" System Clock = No Buffer" and "Reference Clock = Use System Clock" fail during synthesis with the following messages:

ERROR:HDLCompiler:69 - "......\mig_7series_v1_6\user_design\rtl\mig_7series_v1_7.vhd" Line 960: <clk_ref_p> is not declared.
ERROR:HDLCompiler:69 - ".......\mig_7series_v1_6\user_design\rtl\mig_7series_v1_7.vhd" Line 961: <clk_ref_n> is not declared.
ERROR:HDLCompiler:854 - ".......\mig_7series_v1_6\user_design\rtl\mig_7series_v1_7.vhd" Line 496: Unit <arch_mig_7series_v1_6> ignored due to previous errors.


This is expected behavior when "System Clock = No Buffer" and "Reference Clock = Use System Clock" are chosen.

MIG will generate a design without I/O or buffers for the System Clock and Reference Clock.

If the System and Reference Clocks are not manually declared, Synthesis will fail because the mig_7series_v1_7_iodelay_ctrl module needs the reference clocks to be supplied.

If selecting "System Clock = No Buffer" and "Reference Clock = Use System Clock" is required, then you must declare the sys_clk_p/n and clk_ref_p/n signals in the mig_7series_v1_7 module.

Starting with MIG 1.9, this information will be added to the 7 Series FPGAs Memory Interface Solutions User Guide (UG586).

AR# 53299
Date Created 12/12/2012
Last Updated 08/13/2014
Status Active
Type General Article
  • Kintex-7
  • Virtex-7
  • MIG 7 Series