:class:`UART` --- 双工串行通信总线
=======================================

类
-------

.. class:: UART(...)


使用示例l::


    import haascv
    from haascv import driver

    uartObj = driver.uart()#获取UART驱动的对象
    uartObj.open(2, uartObj.DRIVER_HW_DATA_WIDTH_8BIT,
	 115200, uartObj.DRIVER_HW_UART_1_STOP_BIT, 
	 uartObj.DRIVER_HW_FLOW_CONTROL_DISABLED,
	 uartObj.DRIVER_HW_UART_NO_PARITY)#port,bitwidth,baudrate,stop_bits,flow_control,parity
    uart_read_buf = bytearray(4)#定义存储读取的数据的数组
    uart_write_buf = bytearray([97, 98, 99, 100])#定义需要发送的数据

    print(uart_write_buf)#打印发送的数据
    uartObj.write(uart_write_buf)#开始写数据
    readSize = uartObj.read(uart_read_buf)#读数据
    print(readSize)#打印读到数据的大小
    print(uart_read_buf)#打印读取到的数据内容
    uartObj.close()#关闭UART模块


常量
---------

                                                               
.. data:: UART Control

        .. data:: DRIVER_HW_FLOW_CONTROL_DISABLED
        .. data:: DRIVER_HW_FLOW_CONTROL_CTS
        .. data:: DRIVER_HW_FLOW_CONTROL_RTS
        .. data:: DRIVER_HW_FLOW_CONTROL_CTS_RTS

.. data:: UART parity：

        .. data:: DRIVER_HW_UART_NO_PARITY
        .. data:: DRIVER_HW_UART_ODD_PARITY
        .. data:: DRIVER_HW_UART_EVEN_PARITY


.. data:: UART stop bit：

        .. data:: DRIVER_HW_UART_1_STOP_BIT
        .. data:: DRIVER_HW_UART_0_5_STOP_BIT
        .. data:: DRIVER_HW_UART_2_STOP_BIT
        .. data:: DRIVER_HW_UART_1_5_STOP_BIT


.. data:: UART data width：

        .. data:: DRIVER_HW_DATA_WIDTH_5BI
        .. data:: DRIVER_HW_DATA_WIDTH_6BIT
        .. data:: DRIVER_HW_DATA_WIDTH_7BIT
        .. data:: DRIVER_HW_DATA_WIDTH_8BIT
        .. data:: DRIVER_HW_DATA_WIDTH_9BIT


操作函数
-------

.. method:: open(port, bitwidth, baudrate, stop_bits, flow_control, parity)

        配置UART

.. method:: write(uart_write_buf)

        开始写数据

.. method:: read(uart_read_buf)

        读数据

.. method:: close()

        关闭UART模块