LARTET DC-20 Series, User Manual

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CHAPTER 4 COMMUNICATION PROTOCOLS 4-11
DC-20 and DC-21 operation manual
Function 10h
Temperature and humidity can be read using the function 10h.
In the frame, the following codes must be codified.
Unit = 01h
Function = 10h
Start address = 00h 00h
Identifier Protocol
Num
bytes
Unit Function
Start
addr
Num.
regist.
Num.
Bytes
Data
01h 0Ah 00h 00h 00h 09h 01h 10h 00h 00h 00h 01h 02h 50h 54h
In the data field, the characters PT (50h 54h) must be sent.
Response from the display. Example.
In this frame, the data received are 20.4ºC and 42%
Identifier Protocol Number
bytes
Unit Function
01h 0Ah 00h 00h 00h 0Dh 01h 10h
Data
00h 00h 00h 01h 32h 30h 2Eh 34h 20h 34h 32h
4.5.3. Send temperature and humidity
In the repeater displays, the temperature and humidity can be sent using the function 06h
or 10h.
Function 06h. The temperature must be sent to the register 40003 (address 02h) and the
humidity must be sent to the register 40004 (address 03h).
In this example, the identifier is 0618h and the temperature sent is 21.1ºC (D3h)
Frame to send:
Identifier Protocol Num. Bytes Unit Function Start address
Num.
registers
00h 32h 00h 00h 00h 06h 01h 06h 00h 02h 00h D3h
Response from the display:
The response from the display is the same block sent.