六位十六位进制数可逆循环计数器、七段译码器设计，完全有VHDL语言设计，生成SYM文件后，设计top.gdf文件，赋好管脚下载到altera芯片上执行。-Sixteen decimal six reversible cycle counter, seven-segment decoder design, fully VHDL language design, build SYM files, design top.gdf file, assign a good pin downloaded to