介绍
node-red-contrib-davis-vantage是一个npm包，它是一种在Node-RED环境中使用的davis vantage pro2传感器的接口。它可以让Node-RED用户以一种更简单、更方便和更容易的方式来读取和处理davis vantage pro2传感器所获取的数据。
安装
首先，你需要安装Node-RED。你可以通过官方网站下载。接下来，你需要安装node-red-contrib-davis-vantage包。你可以通过下面的命令来安装它：
npm install node-red-contrib-davis-vantage
或者，在Node-RED中的“菜单”上点击“管理面板”然后选择“install”，然后在搜索栏中输入“node-red-contrib-davis-vantage”，并选择“install”。
使用
连接davis vantage pro2传感器
通过串口或者USB连接davis vantage pro2传感器。
在Node-RED中使用
在Node-RED上，在左侧工具栏中可以找到davis vantage节点，你可以从那里开始使用。首先，需要设置节点的“设备路径”，这是你连接davis vantage的串口或者USB端口的路径。然后，点击“deploy”来保存你的设置。
当你需要使用传感器数据时，在你的flow中添加davis节点，使用“msg.payload”接收传感器数据，并在后续的操作中使用它。如下所示：
[ {"id":"be149da.6721b58","type":"davis","z":"7256e25a.13e268","name":"davis node","devicex":"/dev/ttyACM0","topic":"","interval":"4","x":190,"y":120,"wires":[["2c8d7bed.3d9aea","9cb49525.8c94e8"]]},{"id":"2c8d7bed.3d9aea","type":"debug","z":"7256e25a.13e268","name":"","active":true,"console":"false","complete":"payload","x":430,"y":120,"wires":[]},{"id":"9cb49525.8c94e8","type":"function","z":"7256e25a.13e268","name":"process data","func":"//process incoming data\nvar humid = msg.payload.humid;\nvar temp = msg.payload.temp;\n\n//create update sensor data \nvar update = {payload:{}};\nupdate.payload.humidity = humid;\nupdate.payload.temperature = temp;\n\n//send new sensor data\nmsg = update;\n\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","x":410,"y":180,"wires":[["5a0efc7f.8222a8"]]},{"id":"5a0efc7f.8222a8","type":"mqtt out","z":"7256e25a.13e268","name":"","topic":"sensor/data","qos":"","retain":"","broker":"e8c19d89.7edfd8","x":630,"y":180,"wires":[]},{"id":"e8c19d89.7edfd8","type":"mqtt-broker","name":"","broker":"192.168.1.1","port":"1883","clientid":"","usetls":false,"compatmode":true,"keepalive":"60","cleansession":true,"birthTopic":"","birthQos":"0","birthPayload":"","closeTopic":"","closePayload":"","willTopic":"","willQos":"0","willPayload":""} ]
这个例子中，我们将传感器数据接收到的温度和湿度加工处理，并通过MQTT发送到另一个连接。你可以通过自己的需要和设备类型进行调整，从而创建你自己的添加线路。
示例代码
你可以使用以下代码片段来初始化你的davis节点：
[{"id":"be149da.6721b58","type":"davis","z":"7256e25a.13e268","name":"davis node","devicex":"/dev/ttyACM0","topic":"","interval":"4","x":190,"y":120,"wires":[["2c8d7bed.3d9aea","9cb49525.8c94e8"]]}]
结论
node-red-contrib-davis-vantage是一种快速、灵活和易于使用的方案，在Node-RED环境中支持davis vantage pro2传感器数据。它提供了一种简单且方便的方法来使用和处理传感器数据，在给定的节点中轻松实现传感器数据的处理和传输。
来源：JavaScript中文网 ，转载请注明来源 https://www.javascriptcn.com/post/60056da281e8991b448e70ed
