我家里有一个物联网系统和两个温度传感器。其中一个传感器可以在阳光直射下工作几个小时。实际温度总是最低值,所以有时是 temp1,有时是 temp2。
我想要实现的是:
- 从传感器 1 读取温度(通过 MQTT)
- 从传感器 2 读取温度(通过 MQTT)
- 比较值
- 找到最低的并通过 MQTT 发送
- 回到循环阅读
对于这个例子,我可以用注入节点模拟读数
怎么做?我是 Node-Red 的新手,尝试过但没有成功。
这是我的流程:
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