WARNING:Xst:37 - Detected unknown constraint/property "BLACK_BOX". This constraint/property is not supported by the current software release and will be ignored.
WARNING:Xst:1814 - Core <sqrt.ngc> does not contain any logic.
WARNING:Xst:2036 - Inserting OBUF on port <dataout_1<7>> driven by black box <sqrt>. Possible simulation mismatch.
WARNING:Xst:2036 - Inserting OBUF on port <dataout_1<6>> driven by black box <sqrt>. Possible simulation mismatch.
WARNING:Xst:2036 - Inserting OBUF on port <dataout_1<5>> driven by black box <sqrt>. Possible simulation mismatch.
WARNING:Xst:2036 - Inserting OBUF on port <dataout_1<4>> driven by black box <sqrt>. Possible simulation mismatch.
WARNING:Xst:2036 - Inserting OBUF on port <dataout_1<3>> driven by black box <sqrt>. Possible simulation mismatch.
WARNING:Xst:2036 - Inserting OBUF on port <dataout_1<2>> driven by black box <sqrt>. Possible simulation mismatch.
WARNING:Xst:2036 - Inserting OBUF on port <dataout_1<1>> driven by black box <sqrt>. Possible simulation mismatch.
WARNING:Xst:2036 - Inserting OBUF on port <dataout_1<0>> driven by black box <sqrt>. Possible simulation mismatch.
WARNING:Xst:616 - Invalid property "BLACK_BOX 1": Did not attach to sqrt_1.
出现了这么多的警告 然后用modelsim进行前仿真的时候 输出为高阻
求救