vhdl实现VGA接口显示四种图案：横彩条、竖彩条、棋盘格、白屏。文件包含四个模块：clk_div2——二分频（输入50Mhz输出25Mhz）、makecolor产生彩条信号、vgasyn产生行同步hs和列同步vs、行计数器hadddr、列计数器vaddr，vga_main主程序连接前三个模块。-vhdl implementation VGA interface displays four patterns: horizontal color bar, vertical color bars, checkerboard, black and white. File contains four modules: clk_div2- divided by two (input 50Mhz output 25Mhz), makecolor generate color bar signal, vgasyn produce the synchronization and columns simultaneously hs vs, the line counter hadddr, column counter vaddr, vga_main main connecting the first three modules .