JSON protocol:

Modbus Command Set

Modbus Mode Configuration

There is an RS485 communication interface respectively at the aerial plug of the controller and the aerial plug of the end interface board of the RealMan robotic arm. The two RS485 ports can be configured to standard ModbusRTU mode through the JSON protocol. Then the peripherals connected to the interface can be read or written through the JSON protocol.

• Modbus supports switching between RTU and TCP modes. Please configure according to your needs.
• Supports adding multiple ModbusTCP master configurations.

Add Modbus TCP Master add_modbus_tcp_master

• Input Parameter

Parameter	Type	Description
add_modbus_tcp_master	string	Add a new Modbus TCP master configuration.
master_name	string	Name of the TCP master.
ip	int	IP address of the TCP master.
port	int	Port number of the TCP master.

• Output Parameter

Parameter	Type	Description
add_state	bool	true: Added successfully, false: Failed to add.

• Code demo

Input

Add a new master with IP: 127.0.0.1, port: 502, and name: 123.

{"command":"add_modbus_tcp_master","master_name":"123","ip":"127.0.0.1","port":502}

Output

Added successfully:

{
    "command":"add_modbus_tcp_master",
    "add_state":true
}

Failed to add:

{
    "command":"add_modbus_tcp_master",
    "add_state":false
}

Update Modbus TCP Master update_modbus_tcp_master

• Input Parameter

Parameter	Type	Description
add_modbus_tcp_master	string	Add a new Modbus TCP master configuration.
master_name	string	Name of the TCP master.
new_name	string	New name to be modified.
ip	int	IP address to be modified.
port	int	Port number to be modified.

• Output Parameter

Parameter	Type	Description
update_state	bool	true: Updated successfully, false: Failed to update.

• Code demo

Input

Update the master name to: 321.

{"command":"update_modbus_tcp_master","master_name":"123","new_name":"321","ip":"127.0.0.1","port":502}

Output

Updated successfully:

{
    "command":"update_modbus_tcp_master",
    "update_state":true
}

Failed to update:

{
    "command":"update_modbus_tcp_master",
    "update_state":false
}

Delete Modbus TCP Master delete_modbus_tcp_master

• Input Parameter

Parameter	Type	Description
delete_modbus_tcp_master	string	Delete the specified TCP master.
master_name	string	Name of the TCP master to be deleted.

• Output Parameter

Parameter	Type	Description
delete_state	bool	true: Deleted successfully, false: Failed to delete.

• Code demo

Input

Delete the TCP master with the name 123.

{"command":"delete_modbus_tcp_master","master_name":123}

Output

Deleted successfully:

{
    "command": "delete_modbus_tcp_master",
    "delete_state": true
}

Failed to delete:

{
    "command": "delete_modbus_tcp_master",
    "delete_state": false
}

Query Modbus Master List get_modbus_tcp_master_list

• Input Parameter

Parameter	Type	Description
get_modbus_tcp_master_list	string	Query the list of TCP masters.
page_num	int	Page number (omit this parameter when querying all).
page_size	int	Page size (omit this parameter when querying all).
vague_search	string	Fuzzy search (pass this parameter for fuzzy query).

• Output Parameter

Parameter	Type	Description
get_modbus_tcp_master_list	string	Query the list of TCP masters.
total_size	int	Total number of items in the list.
list	object	Detailed information of TCP masters.

• Code demo

Input

Query the current saved Modbus master list, page number: 1, page size: 10, fuzzy search for "file".

{"command":"get_modbus_tcp_master_list","page_num":1,"page_size":10,"vague_search":"file"}

Output

Successful query result:

{
    "command":"get_modbus_tcp_master_list",
    "total_size":2,
    "list":[
        {
            "master_name":"123",
            "ip":"192.168.1.18",
            "port":502
        },
        {
            "master_name":"321",
            "ip":"192.168.1.19",
            "port":502
        }
    ]
}

Failed query:

 {
    "command":"get_modbus_tcp_master_list",
    "get_state":false
}

Query Specified Modbus Master given_modbus_tcp_master

• Input Parameter

Parameter	Type	Description
given_modbus_tcp_master	string	Query the specified TCP master.
master_name	string	Name of the TCP master.

• Output Parameter

Parameter	Type	Description
master_name	string	Name of the TCP master.
ip	string	IP address of the TCP master.
port	int	Port number of the TCP master.

• Code demo

Input

Query the TCP master with the name 123.

{"command":"given_modbus_tcp_master","master_name":"123"}

Output

Query successful:

{
    "command":"given_modbus_tcp_master",
    "master_name":"123",
    "ip":"192.168.1.18",
    "port":502
}

Query failed:

{
    "command":"given_modbus_tcp_master",
    "given_state":false
}

Modbus Status

Query Controller RS485 Mode get_controller_rs485_mode

• Input Parameter

Parameter	Type	Description
get_controller_rs485_mode	string	Query the controller RS485 mode.

• Output Parameter

Parameter	Type	Description
get_controller_rs485_mode	string	Query the controller RS485 mode.
controller_rs485_mode	int	0 represents default RS485 serial communication, 1 represents Modbus RTU master mode, and 2 represents Modbus RTU slave mode.
baudrate	int	Baud rate. (Currently supports 9600, 19200, 38400, 57600, 115200, 230400, 460800)

• Code demo

Query the controller RS485 mode.

Input

{ "command": "get_controller_rs485_mode" }

Output

Feedback on the controller RS485 mode, as follows:

• Current controller RS485 mode: 1;
• Current controller RS485 baud rate: 460800.

{
    "command": "get_controller_rs485_mode",
    "controller_rs485_mode": 1,
    "baudrate": 460800
}

Query end of Tool RS485 Modeget_tool_rs485_mode

• Input Parameter

Parameter	Type	Description
get_tool_rs485_mode	string	Query the end of tool RS485 mode.

• Output Parameter

Parameter	Type	Description
get_tool_rs485_mode	string	Feedback on the end of tool RS485 mode.
tool_rs485_mode	int	0 - represents Modbus RTU master mode, 1 - represents dexterous hand mode, 2 - represents gripper mode.
baudrate	int	Baud rate. (Currently supports 9600, 115200, 460800)

• Code demo

Input

Query the end of tool RS485 mode.

{ "command": "get_tool_rs485_mode" }

Output

Feedback on the end of tool RS485 mode, as follows:

• Current tool - end RS485 mode: 1;
• Current tool - end RS485 baud rate: 460800.

{
  "command": "get_tool_rs485_mode",
  "tool_rs485_mode": 1,
  "baudrate": 460800
}

Configure Controller Communication Port RS485 Mode set_controller_rs485_mode

• Input Parameter

Parameter	Type	Description
set_controller_rs485_mode	string	Configure the controller communication port RS485 mode.
mode	int	0 represents default RS485 serial communication, 1 represents Modbus RTU master mode, and 2 represents Modbus - RTU slave mode.
baudrate	int	Baud rate. (Currently supports 9600, 19200, 38400, 57600, 115200, 230400, 460800)

• Code demo

Input

Configure the port to ModbusRTU mode, as follows:

• Configure the controller RS485 mode: 1;
• Configure the controller RS485 baud rate: 115200.

{"command":"set_controller_rs485_mode","mode":1,"baudrate":115200}

Output

Configuration successful:

{
    "command": "set_controller_rs485_mode",
    "set_state": true
}

Configuration failed:

{
    "command": "set_controller_rs485_mode",
    "set_state": false
}

Configure end of Tool RS485 Mode set_tool_rs485_mode

• Input Parameter

Parameter	Type	Description
set_tool_rs485_mode	string	Configure the end of tool RS485 mode.
mode	int	Communication port, 0 - set the end of tool RS485 port to RTU master, 1 - set the end of tool RS485 port to dexterous hand mode, 2 - set the end of tool RS485 port to gripper mode.
baudrate	int	Baud rate. (Currently supports 9600, 115200, 460800)

• Code demo

Input

Configure the tool - end RS485 mode, as follows:

• Configure the tool - end RS485 mode: 1;
• Configure the tool - end RS485 baud rate: 115200.

{"command":"set_tool_rs485_mode","mode":0,"baudrate":115200}

Output

Configuration successful:

{
    "command": "set_tool_rs485_mode",
    "set_state": true
}

Configuration failed:

{
    "command": "set_tool_rs485_mode",
    "set_state": false
}

End of Tool and end of Controller RTU Modbus Protocol Commands

Read Coils read_modbus_rtu_coils

• Input Parameter

Parameter	Type	Description
read_modbus_rtu_coils	string	Read coils.
address	int	Starting address of the coils.
device	int	Peripheral device address.
num	int	Number of coils.
type	int	0 - controller - end Modbus master; 1 - tool - end Modbus master.

• Output Parameter

Parameter	Type	Description
read_modbus_rtu_coils	string	Read coils.
data	int	Data read (not displayed if read fails).
read_state	bool	Read result (not displayed if read is successful).

• Code demo

Input

Read the coil status, as follows:

• Read coil address: 10;
• Read slave device number: 1;
• Read coil quantity: 1;
• Read port: 0.

{
    "command":"read_modbus_rtu_coils",
    "address":10,
    "device":1,
    "num":1,
    "type":1
}

Output

Read successful, as follows:

• Read command: read_modbus_rtu_coils;
• Read content: 1.

{
    "command": "read_modbus_rtu_coils",
    "data": [1]
}

Read failed:

{
    "command": "set_controller_rs485_mode",
    "read_state": false
}

Write Coils write_modbus_rtu_coils

• Input Parameter

Parameter	Type	Description
write_modbus_rtu_coils	string	Write coil command.
address	int	Starting address of the coil.
device	int	Peripheral device address.
data	int	Content to be written.
port	int	0 - end of controller Modbus master; 1 - end of tool Modbus master.

• Code demo

Input

Write the coil status, as follows:

• Write coil address: 10;
• Write slave device number: 1;
• Write coil content: 1, 0;
• Write port: 0.

{
    "command":"write_modbus_rtu_coils",
    "address":10,
    "data":[1,0],
    "type":1,
    "device":1
}

Output

Write successful:

{
    "command": "write_modbus_rtu_coils",
    "write_state": true
}

Write failed:

{
    "command": "write_modbus_rtu_coils",
    "write_state": false
}

Read Discrete Inputs read_modbus_rtu_input_status

• Input Parameter

Parameter	Type	Description
read_modbus_rtu_input_status	string	Read discrete input.
address	int	Starting address.
device	int	Peripheral device address.
num	int	Number of coils.
type	int	0 - end of controller Modbus master; 1 - end of tool Modbus master.

• Output Parameter

Parameter	Type	Description
read_modbus_rtu_input_status	string	Read discrete input.
data	int	Data read (not displayed if read fails).
read_state	bool	Read result (not displayed if read is successful).

• Code demo

Input

Read the discrete input status, as follows:

• Read discrete input address: 10;
• Read slave device number: 1;
• Read discrete input quantity: 1;
• Read port: 0.

{
    "command":"read_modbus_rtu_input_status",
    "address":10,
    "device":1,
    "num":1,
    "type":1
}

Output

Read successful:

{
    "command": "read_modbus_rtu_input_status",
    "data": [1]
}

Read failed:

{
    "command": "read_modbus_rtu_input_status",
    "read_state": false
}

Write Holding Registers write_modbus_rtu_registers

• Input Parameter

Parameter	Type	Description
write_modbus_rtu_registers	string	Write holding registers.
address	int	Starting address of the holding register.
device	int	Peripheral device address.
data	int	Content to be written.
type	int	0 - end of controller Modbus master; 1 - end of tool Modbus master.

• Code demo

Input

Write data to the holding register, as follows:

• Write holding register address: 10;
• Write slave device number: 1;
• Write holding register content: 15, 20;
• Write port: 0.

{
    "command":"write_modbus_rtu_registers",
    "address":10,
    "data":[15,20],
    "type":1,
    "device":1
}

Output

Write successful:

{
    "command": "write_modbus_rtu_registers",
    "write_state": true
}

Write failed:

{
    "command": "write_modbus_rtu_registers",
    "write_state": false
}

Read Holding Registers read_modbus_rtu_holding_registers

• Input Parameter

Parameter	Type	Description
read_modbus_rtu_holding_registers	string	Read holding registers.
address	int	Starting address.
device	int	Peripheral device address.
num	int	Number of holding registers.
type	int	0 - end of controller Modbus master; 1 - end of tool Modbus master.

• Output Parameter

Parameter	Type	Description
read_modbus_rtu_holding_registers	string	Read holding registers.
data	int	Data read (not displayed if read fails).
read_state	bool	Read result (not displayed if read is successful).

• Code demo

Input

Read data from the holding register, as follows:

• Read holding register address: 10;
• Read slave device number: 1;
• Read holding register quantity: 5;
• Read port: 0.

{
    "command":"read_modbus_rtu_holding_registers",
    "address":10,
    "device":1,
    "num":5,
    "type":1
}

Output

Read successful, read content: 1,2,3,4,5.

{
    "command": "read_modbus_rtu_holding_registers",
    "data": [1,2,3,4,5]
}

Read failed:

{
    "command": "read_modbus_rtu_holding_registers",
    "read_state": false
}

Read Input Registers read_modbus_rtu_input_registers

• Input Parameter

Parameter	Type	Description
read_modbus_rtu_input_registers	string	Read input registers.
address	int	Starting address.
device	int	Peripheral device address.
num	int	Number of input registers.
type	int	0 - end of controller Modbus master; 1 - end of tool Modbus master.

• Output Parameter

Parameter	Type	Description
read_modbus_rtu_input_registers	string	Read input registers.
data	int	Data read (not displayed if read fails).
read_state	bool	Read result (not displayed if read is successful).

• Code demo

Input

Read data from the input register, as follows:

• Read input register address: 10;
• Read slave device number: 1;
• Read input register quantity: 5;
• Read port: 0.

{
    "command":"read_modbus_rtu_input_registers",
    "address":10,
    "device":1,
    "num":5,
    "type":1
}

Output

Read successful:

{
    "command": "read_modbus_rtu_input_registers",
    "data": [1,2,3,4,5]
}

Read failed:

{
    "command": "read_modbus_rtu_input_registers",
    "read_state": false
}

Controller TCP Modbus Protocol Commands

Read Coils read_modbus_tcp_coils

• Input Parameter

Parameter	Type	Description
read_modbus_tcp_coils	string	Read coils.
address	int	Starting address of the coils.
num	int	Number of coils.
master_name	string	Use the Modbus master name in the list (either master_name or IP, if IP and port are available, they will be used preferentially).
ip	string	IP address of the host connection (either master_name or IP, if IP and port are available, they will be used preferentially).
port	int	Port number of the host connection.

• Output Parameter

Parameter	Type	Description
read_modbus_tcp_coils	string	Read coils.
data	int	Data read (not displayed if read fails).
read_state	bool	Read result (not displayed if read is successful).
master_name	string	Use the Modbus master name in the list (either master_name or IP, if IP and port are available, they will be used preferentially).
ip	string	IP address of the host connection (either master_name or IP, if IP and port are available, they will be used preferentially).
port	int	Port number of the host connection.

• Code demo

Input

Use master_name to read the coil status, as follows:

• Read coil address: 10;
• Read slave device number: 1;
• Read coil quantity: 1;
• Host name: "123".

{
    "command":"read_modbus_tcp_coils",
    "address":10,
    "num":1,
    "master_name":"123"
}

Use ip + port to read the coil status, as follows:

• Read coil address: 10;
• Read slave device number: 1;
• Read coil quantity: 1;
• Read IP: "192.168.1.18";
• Read port: 502.

{
    "command":"read_modbus_tcp_coils",
    "address":10,
    "num":1,
    "ip":"192.168.1.18",
    "port":502
}

Output

Use master_name to read successfully, as follows:

{
    "command": "read_modbus_tcp_coils",
    "data": [1],
    "master_name": "123"
}

Read failed, as follows:

{
    "command": "read_modbus_tcp_coils",
    "read_state": false,
    "master_name": "123"
}

Use ip + port to read successfully, as follows:

{
    "command": "read_modbus_tcp_coils",
    "data": [1],
    "ip":"192.168.1.18",
    "port":502
}

Read failed, as follows:

{
    "command": "read_modbus_tcp_coils",
    "read_state": false,
    "ip":"192.168.1.18",
    "port":502
}

Write Coils write_modbus_tcp_coils

• Input Parameter

Parameter	Type	Description
write_modbus_tcp_coils	string	Write coil command.
address	int	Starting address of the coil.
data	int	Content to be written.
master_name	string	Use the Modbus master name in the list (either master_name or IP, if IP and port are available, they will be used preferentially).
ip	string	IP address of the host connection (either master_name or IP, if IP and port are available, they will be used preferentially).
port	int	Port number of the host connection.

• Output Parameter

Parameter	Type	Description
write_modbus_tcp_coils	string	Write coil.
write_state	bool	Write result.
master_name	string	Use the Modbus master name in the list (either master_name or IP, if IP and port are available, they will be used preferentially).
ip	string	IP address of the host connection (either master_name or IP, if IP and port are available, they will be used preferentially).
port	int	Port number of the host connection.

• Code demo

Input

Use master_name to write the coil status, as follows:

• Write coil address: 10;
• Write coil content: 1, 0;
• Write host: "123".

{
    "command":"write_modbus_tcp_coils",
    "address":10,
    "data":[1,0],
    "master_name": "123"
}

Use ip + port to write the coil status, as follows:

• Write coil address: 10;
• Write coil content: 1, 0;
• Write IP: "192.168.1.18";
• Write port: 502.

{
    "command":"write_modbus_tcp_coils",
    "address":10,
    "data":[1,0],
    "ip":"192.168.1.18",
    "port":502
}

Output

Use master_name to write successfully:

{
    "command": "write_modbus_tcp_coils",
    "write_state": true,
    "master_name": "123"
}

Use master_name to write failed:

{
    "command": "write_modbus_tcp_coils",
    "write_state": false,
    "master_name": "123"
}

Use ip + port to write successfully:

{
    "command": "write_modbus_tcp_coils",
    "write_state": true,
    "ip":"192.168.1.18",
    "port":502
}

Use ip + port to write failed:

{
    "command": "write_modbus_tcp_coils",
    "write_state": false,
    "ip":"192.168.1.18",
    "port":502
}

Read Discrete Inputs read_modbus_tcp_input_status

• Input Parameter

Parameter	Type	Description
read_modbus_tcp_input_status	string	Read discrete input.
address	int	Starting address of the discrete input.
num	int	Number of discrete inputs.
master_name	string	Use the Modbus master name in the list (either master_name or IP, if IP and port are available, they will be used preferentially).
ip	string	IP address of the host connection (either master_name or IP, if IP and port are available, they will be used preferentially).
port	int	Port number of the host connection.

• Output Parameter

Parameter	Type	Description
read_modbus_tcp_input_status	string	Read discrete input.
data	int	Data read (not displayed if read fails).
read_state	bool	Read result (not displayed if read is successful).
master_name	string	Use the Modbus master name in the list (either master_name or IP, if IP and port are available, they will be used preferentially).
ip	string	IP address of the host connection (either master_name or IP, if IP and port are available, they will be used preferentially).
port	int	Port number of the host connection.

• Code demo

Input

Use master_name to read the discrete input status, as follows:

• Read discrete input address: 10;
• Read discrete input quantity: 1;
• Read host: "123".

{
    "command":"read_modbus_tcp_input_status",
    "address":10,
    "num":1,
    "master_name": "123"
}

Use ip + port to read the discrete input status, as follows:

• Read discrete input address: 10;
• Read discrete input quantity: 1;
• Write IP: "192.168.1.18";
• Write port: 502.

{
    "command":"read_modbus_tcp_input_status",
    "address":10,
    "num":1,
    "ip":"192.168.1.18",
    "port":502
}

Output

Use master_name to read successfully:

{
    "command": "read_modbus_tcp_input_status",
    "data": [1],
    "master_name": "123"
}

Use master_name to read failed:

{
    "command": "read_modbus_tcp_input_status",
    "read_state": false,
    "master_name": "123"
}

Use ip + port to read successfully:

{
    "command": "read_modbus_tcp_input_status",
    "data": [1],
    "ip":"192.168.1.18",
    "port":502
}

Use ip + port to read failed:

{
    "command": "read_modbus_tcp_input_status",
    "read_state": false,
    "ip":"192.168.1.18",
    "port":502
}

Write Holding Registers write_modbus_tcp_registers

• Input Parameter

Parameter	Type	Description
write_modbus_tcp_registers	string	Write holding register command.
address	int	Starting address of the holding register.
data	int	Content to be written.
master_name	string	Use the Modbus master name in the list (either master_name or IP, if IP and port are available, they will be used preferentially).
ip	string	IP address of the host connection (either master_name or IP, if IP and port are available, they will be used preferentially).
port	int	Port number of the host connection.

• Output Parameter

Parameter	Type	Description
write_modbus_tcp_registers	string	Write holding register.
write_state	bool	Write result.
master_name	string	Use the Modbus master name in the list (either master_name or IP, if IP and port are available, they will be used preferentially).
ip	string	IP address of the host connection (either master_name or IP, if IP and port are available, they will be used preferentially).
port	int	Port number of the host connection.

• Code demo

Input

Use master_name to write data to the holding register, as follows:

• Write holding register address: 10;
• Write holding register content: 15, 20;
• Write host: "123".

{
    "command":"write_modbus_tcp_registers",
    "address":10,
    "data":[15,20],
    "master_name": "123"
}

Use ip + port to write the holding register status, as follows:

• Write holding register address: 10;
• Write holding register content: 15, 20;
• Write IP: "192.168.1.18";
• Write port: 502.

{
    "command":"write_modbus_tcp_registers",
    "address":10,
    "data":[15,20],
    "ip":"192.168.1.18",
    "port":502
}

Output

Use master_name to write successfully:

{
    "command": "write_modbus_tcp_registers",
    "write_state": true,
    "master_name": "123"
}

Use master_name to write failed:

{
    "command": "write_modbus_tcp_registers",
    "write_state": false,
    "master_name": "123"
}

Use ip + port to write successfully:

{
    "command": "write_modbus_tcp_registers",
    "write_state": true,
    "ip":"192.168.1.18",
    "port":502
}

Use ip + port to write failed:

{
    "command": "write_modbus_tcp_registers",
    "write_state": false,
    "ip":"192.168.1.18",
    "port":502
}

Read Holding Registers read_modbus_tcp_holding_registers

• Input Parameter

Parameter	Type	Description
read_modbus_tcp_holding_registers	string	Read holding register.
address	int	Starting address of the holding register.
num	int	Number of holding registers.
master_name	string	Use the Modbus master name in the list (either master_name or IP, if IP and port are available, they will be used preferentially).
ip	string	IP address of the host connection (either master_name or IP, if IP and port are available, they will be used preferentially).
port	int	Port number of the host connection.

• Output Parameter

Parameter	Type	Description
read_modbus_tcp_holding_registers	string	Read holding register.
data	int	Data read (not displayed if read fails).
read_state	bool	Read result (not displayed if read is successful).
master_name	string	Use the Modbus master name in the list (either master_name or IP, if IP and port are available, they will be used preferentially).
ip	string	IP address of the host connection (either master_name or IP, if IP and port are available, they will be used preferentially).
port	int	Port number of the host connection.

• Code demo

Input

Use master_name to read the holding register status, as follows:

• Read holding register address: 10;
• Read holding register quantity: 1;
• Read host: "123".

{
    "command":"read_modbus_tcp_holding_registers",
    "address":10,
    "num":1,
    "master_name": "123"
}

Use ip + port to read the holding register status, as follows:

• Read holding register address: 10;
• Read holding register quantity: 1;
• Write IP: "192.168.1.18";
• Write port: 502.

{
    "command":"read_modbus_tcp_holding_registers",
    "address":10,
    "num":1,
    "ip":"192.168.1.18",
    "port":502
}

Output

Use master_name to read successfully:

{
    "command": "read_modbus_tcp_holding_registers",
    "data": [1],
    "master_name": "123"
}

Use master_name to read failed:

{
    "command": "read_modbus_tcp_holding_registers",
    "read_state": false,
    "master_name": "123"
}

Use ip + port to read successfully:

{
    "command": "read_modbus_tcp_holding_registers",
    "data": [1],
    "ip":"192.168.1.18",
    "port":502
}

Use ip + port to read failed:

{
    "command": "read_modbus_tcp_holding_registers",
    "read_state": false,
    "ip":"192.168.1.18",
    "port":502
}

Read Input Registers read_modbus_tcp_input_registers

• Input Parameter

Parameter	Type	Description
read_modbus_tcp_input_registers	string	Read input register.
address	int	Starting address of the input register.
num	int	Number of input registers.
master_name	string	Use the Modbus master name in the list (either master_name or IP, if IP and port are available, they will be used preferentially).
ip	string	IP address of the host connection (either master_name or IP, if IP and port are available, they will be used preferentially).
port	int	Port number of the host connection.

• Output Parameter

Parameter	Type	Description
read_modbus_tcp_input_registers	string	Read input register.
data	int	Data read (not displayed if read fails).
read_state	bool	Read result (not displayed if read is successful).
master_name	string	Use the Modbus master name in the list (either master_name or IP, if IP and port are available, they will be used preferentially).
ip	string	IP address of the host connection (either master_name or IP, if IP and port are available, they will be used preferentially).
port	int	Port number of the host connection.

• Code demo

Input

Use master_name to read the input register status, as follows:

• Read input register address: 10;
• Read input register quantity: 1;
• Read host: "123".

{
    "command":"read_modbus_tcp_input_registers",
    "address":10,
    "num":1,
    "master_name": "123"
}

Use ip + port to read the input register status, as follows:

• Read input register address: 10;
• Read input register quantity: 1;
• Write IP: "192.168.1.18";
• Write port: 502.

{
    "command":"read_modbus_tcp_input_registers",
    "address":10,
    "num":1,
    "ip":"192.168.1.18",
    "port":502
}

Output

Use master_name to read successfully:

{
    "command": "read_modbus_tcp_input_registers",
    "data": [1],
    "master_name": "123"
}

Use master_name to read failed:

{
    "command": "read_modbus_tcp_input_registers",
    "read_state": false,
    "master_name": "123"
}

Use ip + port to read successfully:

{
    "command": "read_modbus_tcp_input_registers",
    "data": [1],
    "ip":"192.168.1.18",
    "port":502
}

Use ip + port to read failed:

{
    "command": "read_modbus_tcp_input_registers",
    "read_state": false,
    "ip":"192.168.1.18",
    "port":502
}