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AR# 16410

Virtex-II Configuration - The INIT pin does not go Low after the PROGRAM pin goes Low


After the PROGRAM_B pin is pulled Low, the INIT_B pin is not also pulled Low.


During configuration, INIT_B is pulled Low internally by the FPGA when PROGRAM_B is pulled Low. After the FPGA has initialized, the INIT_B pin is released by the FPGA and configuration may begin.

If the PWRDWN_B pin (_B denoting active Low) is held Low, the FPGA will not pull INIT_B Low when PROGRAM_B is pulled Low, and the FPGA will not configure.

Ensure that PWRDWN_B is not being held Low externally, and be sure that the BitGen "PowerdownPin" option is set to "Pull-up" (it is set to "Pull-up" by default). You can verify this option in the BitGen report (.bgn).

For more information on the PWRDWN pin, please see (Xilinx Answer 12763).

AR# 16410
Date 12/15/2012
Status Active
Type General Article