My design uses ISERDES width expansion as described in the Virtex-4 documentation. When I try to implement this design, the following error occurs:
"ERROR:LIT:389 - The D, CLK and CLKDIV pins must be connected for ISERDES symbol "My_ISERDES"."
What causes this error and how can I resolve this problem?
This check prevents situations where the "D" input is driven by logic and causes unroutable connections, and should also allow cascaded ISERDES.
This issue has been fixed in ISE version 8.2i. For earlier ISE revisions, this error can be avoided by setting the environment variable:
Linux and Solaris
setenv XIL_MAP_NO_ISERDES_PIN_DRC 1
For general information about setting ISE environment variables, see (Xilinx Answer 11630).