Device register manual

Modbus communication protocol for fan coil unit controller

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Modbus communication protocol for fan coil unit controller
Modbus communication protocol for fan coil unit controllerFigure
Physical interface: RS485
Communication protocol: ModBus／RTU
Baud rate setting: 9600, N,8,1
Supported function codes:0x03,0x04And0x06
00Broadcast addressNo return value

Input Register(Read operation, Function code0x04)

Variable numberVariable descriptionCompanyVariable valuesMapping address
30001Return air temperature0.1℃0－50.0℃0x00
30002Fan status---0=stop it,2=Low speed,4=Medium speed,8=High speed0x01
30003Electric water valve status---0=stop it, 1=function0x02

Holding Register (Read operation, Function code0x03; Write operation, Function code0x06)

Variable numberVariable descriptionCompanyVariable valuesMapping address
40001Mode operation---1=Refrigeration,4=improve air circulation heating,8=Wind speed setting0x00
40002Low speed---2=Medium speed,4=High speed,8=Temperature setting0x01
40003Fan coil unit status0.1℃5.0－35.0℃0x02
40004Shutdown---0=function, 1=The upper computer reads the status of temperature controller 1 #0x03

1, Register (To30001The corresponding communication starting address is30003,To0x00Main station request0x02)

Response from the stationThe device address of the master station accessing the slave stationParameter
Field Name(Hex)Field Name(Hex)
Slave Address01Slave Address01The master station accesses the slave station
Function Code04Function Code04Function code of registerInputThe number of bytes responded by the slave station to the master station
Starting Address Hi00Byte Count06Decimal is
Starting Address Lo00Input Reg.00 Hi01Reg.00=0X0118, Due to temperature amplification280, Double10What is the current return air temperature, Degree28.0The current wind speed is high.
Quantity of Input Reg. Hi00Input Reg.00 Lo18
Quantity of Input Reg. Lo03Input Reg.01 Hi00Reg.00=0X0008, The current wind speed is high.
CRC HiB0Input Reg.01 Lo08
CRC Lo0BInput Reg.02 Hi00Reg.00=0X0001, The current water valve is open.
Input Reg.02 Lo01
CRC Hi01The current frame of dataCRCComparison is0X0142, If the data is different, the verification code will change accordingly.
CRC LO42

2, The upper computer reads the parameters of temperature controller 1 # (Register40001To40004,The corresponding communication starting address is0x00To0x03)

Main station requestResponse from the stationParameter
Field Name(Hex)Field Name(Hex)
Slave Address01Slave Address01The device address of the master station accessing the slave station
Function Code03Function Code03The master station accesses the slave stationHoldingFunction code of register
Starting Address Hi00Byte Count08The number of bytes responded by the slave station to the master station
Starting Address Lo00Holding Reg.00 Hi00Reg.00=0X0001, The current operating mode is cooling.
Quantity of Holding Reg. Hi00Holding Reg.00 Lo01
Quantity of Holding Reg. Lo04Holding Reg.01 Hi00Reg.01=0X0008, The current wind speed setting is high wind speed.
CRC Hi44Holding Reg.01 Lo08
CRC Lo09Holding Reg.02 Hi00Reg.02=0X00F0, Decimal is240, Due to temperature amplification10Double, What is the current temperature setting24.0Degree.
Holding Reg.02 LoF0
Holding Reg.03 Hi00Reg.03=0X0001, The current state is the boot state.
Holding Reg.03 Lo01
CRC HiA5The current frame of dataCRCComparison is0XA525, If the data is different, the verification code will change accordingly.
CRC LO25

3, Set the mode parameters of temperature controller 1 # on the upper computer (Register40001,The corresponding communication starting address is0x00)

Main station requestResponse from the stationParameter
Field Name(Hex)Field Name(Hex)
Slave Address01Slave Address01The device address of the master station accessing the slave station
Function Code06Function Code06Master station rewrites slave stationHoldingParameters of registers
Starting Address Hi00Starting Address Hi00Holding Reg.Mode address0X0000.
Starting Address Lo00Starting Address Lo00
Holding Reg. Value Hi00Holding Reg. Value Hi00Reg.00=0X0008, Change the mode to heating.
Holding Reg. Value Lo08Holding Reg. Value Lo08
CRC Hi88CRC Hi88The current frame of dataCRCComparison is0X880C, If the data is different, the verification code will change accordingly.
CRC Lo0CCRC Lo0C

4, Set the wind speed parameter of temperature controller 1 # on the upper computer (Register40002,The corresponding communication starting address is0x01)

Main station requestResponse from the stationParameter
Field Name(Hex)Field Name(Hex)
Slave Address01Slave Address01The device address of the master station accessing the slave station
Function Code06Function Code06Master station rewrites slave stationHoldingParameters of registers
Starting Address Hi00Starting Address Hi00Holding Reg.Wind speed address0X0001.
Starting Address Lo01Starting Address Lo01
Holding Reg. Value Hi00Holding Reg. Value Hi00Reg.00=0X0004, Rewrite the wind speed to medium speed.
Holding Reg. Value Lo04Holding Reg. Value Lo04
CRC HiD9CRC HiD9The current frame of dataCRCComparison is0XD9C9, If the data is different, the verification code will change accordingly.
CRC Lo0CCRC Lo0C

5, Set the temperature parameters of the 1 # thermostat on the upper computer (Register40003,The corresponding communication starting address is0x02)

Main station requestResponse from the stationParameter
Field Name(Hex)Field Name(Hex)
Slave Address01Slave Address01The device address of the master station accessing the slave station
Function Code06Function Code06Master station rewrites slave stationHoldingParameters of registers
Starting Address Hi00Starting Address Hi00Holding Reg.Temperature setting address0X0002.
Starting Address Lo02Starting Address Lo02
Holding Reg. Value Hi00Holding Reg. Value Hi00Reg.00=0X00DC, decimal system220, That is, temperature setting22.0Degree.
Holding Reg. Value LoDCHolding Reg. Value LoDC
CRC Hi29CRC Hi29The current frame of dataCRCComparison is0X2993, If the data is different, the verification code will change accordingly.
CRC Lo93CRC Lo93

6, Set the on/off status of temperature controller 1 # on the upper computer (Register40004,The corresponding communication starting address is0x03)

Main station requestResponse from the stationParameter
Field Name(Hex)Field Name(Hex)
Slave Address01Slave Address01The device address of the master station accessing the slave station
Function Code06Function Code06Master station rewrites slave stationHoldingParameters of registers
Starting Address Hi00Starting Address Hi00Holding Reg.Power on/off operation address0X0003.
Starting Address Lo03Starting Address Lo03
Holding Reg. Value Hi00Holding Reg. Value Hi00Reg.00=0X0001, Turn on the thermostat immediately.
Holding Reg. Value Lo01Holding Reg. Value Lo01
CRC HiB8CRC HiB8The current frame of dataCRCComparison is0XB80A, If the data is different, the verification code will change accordingly.
CRC Lo0ACRC Lo0A
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