Can you turn on and off the CRC check for Virtex or Spartan-II as you can for
the 4k family?
No, BitGen does not have a switch to disable CRC for Virtex or Spartan-II. The
CRC check is differs between these and the XC4000 series and other FPGA
families. In previous families, CRC is checked after each frame. For Virtex and
Spartan-II, a check occurs just prior to loading the last frame and again at the
very end of the bitstream.
For more information on CRC checking in Virtex refer to Xilinx Application
Note (XAPP138) - "Virtex Configuration and Readback," available at: