说明：  在FPGA外扩用FT2232 实现UART TO USB 2.0 的通信。
(The FT2232H is a USB2.0 Hi-Speed USB Device to FIFO IC. This core allows the use of this chip with an FGPA design in high speed FT245 style synchronous FIFO mode. Data rates up to 25 mbytes/s can be achieved. The core has internal FIFOs on the receive and transmit for improved throughput. For more information see FTDI s appnote "AN_130_FT2232H_Used_In_FT245 Synchronous FIFO Mode.pdf" Included: VHDL core, NIOS test application, PC test application )