求助这个警告是什么意思？怎么改！谢谢大佬！

大圣归来 · 发表于 2017-10-21 22:11:47

WARNING:HDLCompiler:1499 - "D:\FPGA project\breath_led\breath_led.v" Line 21: Empty module <breath_led> remains a black box.
工程在编译完后出现了这个警告，这个警告是什么意思啊？要怎么改正呢？
后面还跟着这两个警告：
WARNING:Xst:647 - Input <sclk> is never used. This port will be preserved and left unconnected if it belongs to a top-level block or it belongs to a sub-block and the hierarchy of this sub-block is preserved.
WARNING:Xst:647 - Input <rst_n> is never used. This port will be preserved and left unconnected if it belongs to a top-level block or it belongs to a sub-block and the hierarchy of this sub-block is preserved.

大概意思是我没用到那两个输入量？但是代码里面我写了呀！这又是怎么一回事呢？谢谢大佬解答！