Section 12

Digital / NPN / Frequency Signal Inputs & Temp/Humidity Sensors

⏱️ Estimated Duration: 20 mins

Master the types and wiring methods of digital inputs, and learn to access common digital sensors.

📚 Learning Points

Switching Signals: Introduce the characteristics of passive switching (dry contact) and active switching (wet contact)
Switching Sensor Wiring: Using water level sensors (float switches) and limit switches as examples to demonstrate passive/active wiring
NPN (Open Collector) Signal: Introduce the wiring method of NPN output sensors (such as photoelectric switches)
Pulse/Frequency Input: Explain how to access flowmeters with pulse output or frequency signals for counting or frequency detection
IIC Digital Communication Interface: Demonstrate the hardware access of the IIC interface (SCL/SDA/GND/3V) and accessing IIC temperature and humidity sensors (such as SHT30)
Input Parameter Status View: View switching status, frequency values, temperature/humidity, and other data in the app

📝

Content in Progress

Detailed content for this section is currently being written. Please stay tuned. You can browse other completed sections or check out the MQTT Protocol Documentation .