内含有完整的UART代码，包括发送和接受，且有testbench，可以直接仿真调试-Contain complete UART code, including send and receive and there testbench, can directly Simulation debugging

verilog实现串口通讯，包括verilog代码和testbench代码-verilog serial communication, including the verilog code and testbench Code