基于FPGA的数码管控制程序。旨在通过此程序设计熟悉VHDL程序设计方法与硬件控制方法。 本程序下载后，数码管高两位加计数，低两位减计数，按reset后清零。-FPGA-based digital control procedures. This program is designed to be familiar with VHDL programming design methods and hardware control methods. After this program dow