CHAPTER 4
COMMUNICATION PROTOCOLS
4-2
DC-24 and DC-25 operation manual
4.1.1.
Displays DC-24/X. Read values from the display
To read the current values of the temperature and humidity, the following message must be sent:
Header
Address
Code
End of block
Characters
@
High Low
P T
Carry return
Decimal
64d
80d 84d
13d
Hexadecimal
40h
50h 54h
0Dh
The address of the display is formed by 2 digits between 0 and 99
Example: Data request to the display at address 15
Header
Address
Code
End of block
Characters
@
1 5
P T
Carry return
Decimal
64d
49d 53d
80d 84d
13d
Hexadecimal
40h
31h 35h
50h 54h
0Dh
Response from the display
The response message from the display is the following:
Header
Address
Code
Temp
Space
Hum
End of block
Characters
@
High Low
P T
T T , T
H H
Carry return
Decimal
64d
80d 84d
32d
13d
Hexadecimal
40h
50h 54h
20d
0Dh
The address returned is the one of the display
Temperature and humidity are sent in the indicated format, separated by a comma.
Response frame example. Temperature = 24,7 and relative humidity = 63%
Header
Address
Code
Temp
Space
Hum
End of block
Characters
@
1 5
P T
24,7
63
Carry return
Decimal
64d
49d 53d
80d 84d
50d 52d 44d 55d
32d
54d 51d
13d
Hexadecimal
40h
31h 35h
50h 54h
32h 34h 2Ch 37h
20h
36h 33h
0Dh
4.1.2.
Displays DC-25/X. Send values to the display
To send values of the temperature and humidity to the display, the following message must be
sent:
Header
Address
Code
Temp
Space
Hum
End of block
Characters
@
High Low
V T
T T , T
H H
Carry return
Decimal
64d
86d 84d
32d
13d
Hexadecimal
40h
56h 54h
20d
0Dh
The address of the display is formed by 2 digits between 0 and 99