S&P CADB-HE BASIC Series Manual page 27

Basic characteristics of the Modbus-RTU controller
Addressing
Diffusion
Transmission speed
Parity
Mode
Electrical interface
Connector type
MODBUS message
Address
8 bits
The format for each byte in RTU mode is:
Code system: 8–bit binary
Bits per Byte: 1 bit of START (start)
8 data bits, the most signifi cant bit is sent the fi rst
1 bit for the parity (Even parity required)
1 bit of STOP (end)
Modbus memory map
Nº Type of register
Reg.
General confi guration
9 Coil
7 Coil
0 Coil
0 Input Register
1 Input Register
2 Input Register
3 Input Register
4 Input Register
Slave: confi gurable address from 1 to 247
Yes
9600
EVEN
RTU
RS-485 2W-wired or RS232
RJ 45
Function
8 bits
Description Range
Unit status 0
1
Contact CLP 0
start/stop
1
Fans working mode 0
1
Vin 0 - 10
TODA -30 - 50
TETA -30 - 50
TEHA -30 - 50
TSUP -30 - 50
Data
N x 8 bits
Data Default
value
Off 1
Run
Contact NO 0
Contact NC
VAV mode 0
COP mode
V
ºC
ºC
ºC
ºC
CRC verifi cation
16 bits
R/W Comments
R/W
R/W
R/W
R Analogic input value (V)
R Outdoor Air Temperature
(Fresh air)
R Extract Air Temperature
(Foul air)
R Exhaust Air Temperature
(Foul air)
R Supply Air Temperature
(Fresh air)
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