UART module

UART(通用异步收发传输器)是一种通信协议，在本项目中充当了客户端和开发板交互的渠道。

UART(Universal Asynchronous Transceiver Transmitter) is a communication protocol that acts as a channel for interaction between the client and the development board in this project.

在该demo中, 一个封装好的Uart模块已经提供。你无法直接将开发板的操作映射到软件中，所以你需要这样的Uart模块，将开发板的操作传递给软件，再把软件的反馈信号传回开发板。

Here is a provided Uart module. It’s impossible to map your operations on the EGO1 board to the software, hence you need a UART module like this to transmit the operations from the EGO1 board to the software and then relay the software's feedback signals back to the EGO1 board.

module UART(
  input        clock,             // uart clock. Please use 16 x BaudRate. (such as: 9600 * 16 = 153600Hz)
               reset,             // reset on high.
               io_pair_rx,        // rx, connect to R5 pin please
  input  [7:0] io_dataIn_bits,    // (a) byte from DevelopmentBoard => GenshinKitchen
  output       io_pair_tx,        // tx, connect to T4 pin please
               io_dataIn_ready,   // referring (a) £»pulse 1 after a byte tramsmit success.
           reg io_dataOut_valid,  // referring (b)
  output reg [7:0] io_dataOut_bits    // (b) byte from GenshinKitchen => DevelopmentBoard, only available if io_dataOut_valid=1
);

在你设计的模块中，你需要控制i_data_bit，这是Uart向软件发送的8个比特数据。而软件返回给Uart的8个比特数据存放在o_data_bit中（output_valid=1时有效），你需要接收该数据并使用该数据控制你程序的行为。

In this module, you should modify i_data_bit which is the 8-bits-data send to software by Uart. The 8-bits-data returned to Uart by software is in o_data_bit (only available when output_valid=1), which should be received to control your code.

当然,数据在客户端和开发板之间传输是需要时间的. 因此,io_dataIn_ready和io_dataOut_valid被用于判断数据的传输情况. io_dataIn_ready=1意味着当前byte已经发送给客户端,可以传输下一个byte. io_dataOut_valid=1意味着从客户端接收到了一个byte,你可以分析数据中的内容了.

Of course, it takes time for data to transfer between the client and the development board. Therefore,io_dataIn_ready and io_dataOut_valid are used to determine the transmission of the data. io_dataIn_ready=1 means that the current byte has been sent to the client and the next byte can be transmitted. io_dataOut_valid=1 means that a byte was received from the client and you can analyze the contents of the data.

你可能会需要用到时钟分频，为你的Uart模块提供合适的时间信号，即clock信号。这个时钟的频率大致为Uart比特率的16倍，且误差小于1%。例如软件中默认比特率为9600，那么Uart模块的时钟频率应当为153600Hz。

You may need a new clock with a divided frequency, which can provide a correct time signal to Uart. The clock frequency for this UART module should be approximately 16 times the UART bit rate, with an error of less than 1%. For example, the default bit rate in the software is 9600, then the UART module's clock frequency should be 153600 Hz.