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LHT52 Temperature & Humidity sensor      25  /  40 
2.8 LED Indicator   
The LHT52 has a triple color LED which for easy showing different stage.   
 
In a normal working state: 
✓  When the node is restarted, GREEN, RED and BLUE are sequentially lit. 
✓  During OTAA Join:   
For each Join Request uplink, the GREEN LED will blink once.   
Once Join Successful: the GREEN LED will be solid on for 5 seconds.   
 
✓  After joined, for each uplink, the BLUE LED or GREEN LED will blink once.   
  BLUE LED when external sensor is connected 
  GREEN LED when external sensor is not connected   
✓  For each success downlink, the PURPLE LED will blink once 
 
 
In AT Command Mode:   
If user use console cable to send AT Command to LHT52, the RED LED will always on until: 
➢  Power off/on LHT52 
➢  Press reset button of LHT52.   
➢  Send an AT Command: AT+CLPM=1 
 
2.9 Button   
Press the button LHT52 will reset and join network again.