Why do I see the following BitGen error when running theexample design through the ISE DesignSuite13.2 tools?
"ERROR:Bitgen:342 - This design contains pins which are not constrained (LOC) to a specific location or have an undefined I/O Standard (IOSTANDARD). This may cause I/O contention or incompatibility with the board power or connectivity affecting performance, signal integrity or in extreme cases cause damage to the device or the components to which it is connected.
To prevent this error, it is highly recommended to specify all pin locations and I/O standards to avoid potential contention or conflicts and to allow proper bitstream creation.
To demote this error to a warning and allow bitstream creation with unspecified I/O location or standards, you can apply the following -g UnconstrainedPins:Allow" BitGen switch.
To remove this error, please change the "bitgen" line in the <core_name>/implement/implement.sh or
<core_name>/implement/implement.bat file to:
bitgen -j -g UnconstrainedPins:Allow -w routed routed mapped.pcf
A bitstream will not be produced. When all I/O pins are placed and constrained to the appropriate I/O standards the -j and -g UnconstrainedPins:Allow switches can be removed and BitGen will generate a bitstream for download.
For more details on this issue please see (Xilinx Answer 41615).
For Release Notes and Known Issues for the Logicore OBSAI, please see (Xilinx Answer 36971).