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Based on the memory part and frequency selected through the GUI, MIG selects the appropriate CL and CWL. When generating a custom part, MIG will use the selected base part along with the frequency to determine the appropriate CL and CWL.
To view the CL and CWL values the tool generated, open the example_top.v/.vhd (or <user_design>.v/.vhd for 7 Series designs andmemc_ui_top.v/.vhd module (located in 'rtl/ip_top' directory) for Virtex-6 designs) and locate the CL and CWL parameters.
Modification of these parameters should not be necessary. Ensure the correct base part is chosen for the custom part flow as this will ensure the CL and CWL parameters are set correctly.