该代码实现了FPGA对USB芯片68013的读写，语言是VERLOD，试验通过。-The code to achieve the FPGA read and write 68013 on the USB chip, the language is VERLOD, through the test.

The Nexys4 DDR board is a complete, ready-to-use digital circuit development platform based on the latest Artix-7™ Field Programmable Gate Array (FPGA) Xilinx® . With its large, high-capacity FPGA (Xilinx part number XC7A100T-1CSG324C)