General Description: In Design Manager versions 4.1isp3 through 4.2isp2, the default value of the "Unused Pin" option is "PULLUP" when a Virtex or Virtex-E device is targeted. However, if none of the options in the GUI are changed, Design Manager does not pass the default value of the Unused Pin option to BitGen. Consequently, the device that is configured by the generated file contains unused pins that have "PULLDOWN" registers by default.
You may work around this problem in two ways:
1. Any option change will cause the "Unused Pin" option to be added into BitGen; therefore, if you change anything in the GUI, then set it back to the original options, the "PULLUP" value for the "Unused Pin" option will be added into BitGen.
2. You may also use BitGen from the command line to explicitly set your desired options.