几篇解读FPGA内部时序问题的好文章，从最近本的Tco,Tsu，Th等入门。一直到如何对时序进行约束，如何处理各种影响FPGA时钟的因素。如何读懂时序图（Interpreting the Timing Diagram） -FPGA internal timing problems read several good articles, from the most recent of Tco, Tsu, Th and other entry. How the timing has to be co