485通信
===================

.. figure:: /_static/products/ledong-module/static/图片/485通讯.png
	:width: 55%
	:align: center

概述
--------------------
485通信模块，连接气象站套件（含风速、风向），将485信号通过串口发送到主控板中。



技术参数
-------------------

工作电压： VCC 3.3V -5V

模块尺寸：32*48mm

固定安装：2个兼容塑料积木通孔

通讯方式：串口，波特率4800


引脚 定义 
-------------------

=======  ======== 
引脚       定义   
=======  ========  
GND       地
VCC       电源  
TX        串口发送
RX        串口接收
=======  ======== 



示例程序
-------------------

**气象站代码**

.. code-block:: python

    from mpython import *

    from bluebit import WEATHER

    w = WEATHER(uart_num=1,pin_tx=Pin.P16,pin_rx=Pin.P15)

    import time

    def get_wind_dir():
        try:
            direction = w.read_wind_direction()[0]
            if(direction == 0):
                return "北风"
            elif(direction == 1):
                return "东北风"
            elif(direction == 2):
                return "东风"
            elif(direction == 3):
                return "东南风"
            elif(direction == 4):
                return "南风"
            elif(direction == 5):
                return "西南风"
            elif(direction == 6):
                return "西风"
            elif(direction == 7):
                return "西北风"
        except:
            pass

    def get_wind_power(arg):
        try:
            wind_power = w.read_wind_power()
            if(arg==0):
                return wind_power[0]
            else:
                return wind_power[1]
        except:
            pass

    def get_rainfall():
        try:
            rainfall = w.read_rainfall()
            return rainfall
        except:
            pass
    while True:
        print('风向：' + str(get_wind_dir()))
        time.sleep(0.5)
        print('风速：' + str(get_wind_power(0)))
        time.sleep(0.5)
        print('降雨量：' + str(get_rainfall()))
        print('===')
        time.sleep(1)

.. figure:: /_static/products/ledong-module/static/examples/气象站.png
	:width: 100%
	:align: center