Class of pyModbusTCP.client

pyModbusTCP.client.ModbusClient

class pyModbusTCP.client.ModbusClient

Client Modbus TCP

__init__()

Constructor

Returns:Object ModbusClient Return type:ModbusClient

close()

Close TCP connection

Returns:close status (True for close/None if already close) Return type:bool or None

debug(debug=None)

Get or set debug mode

Parameters:debug (bool or None) – debug state or None for get value Returns:debug state or None if set fail Return type:bool or None

host(hostname=None)

Get or set host (IPv4 or hostname like ‘plc.domain.net’)

Parameters:hostname (str or None) – hostname/IPv4 address or None for get value Returns:hostname or None if set fail Return type:str or None

is_open()

Get status of TCP connection

Returns:status (True for open) Return type:bool

last_error()

Get last error code

Returns:last error code Return type:int

last_except()

Get last except code

Returns:last except code Return type:int

mode(mode=None)

Get or set modbus mode (TCP or RTU)

Parameters:mode (int) – mode (MODBUS_TCP/MODBUS_RTU) to set or None for get value Returns:mode or None if set fail Return type:int or None

open()

Connect to modbus server (open TCP connection)

Returns:True if connect or None if error Return type:bool or None if error

port(port=None)

Get or set TCP port

Parameters:port (int or None) – TCP port number or None for get value Returns:TCP port or None if set fail Return type:int or None

read_coils(bit_addr, bit_nb=1)

Modbus function READ_COILS (0x01)

Parameters:

• bit_addr (int) – bit address (0 to 65535)
• bit_nb (int) – number of bits to read (1 to 125)

Returns:

bits list or None if error

Return type:

list of bool or None

read_discrete_inputs(bit_addr, bit_nb=1)

Modbus function READ_DISCRETE_INPUTS (0x02)

Parameters:

• bit_addr (int) – bit address (0 to 65535)
• bit_nb (int) – number of bits to read (1 to 125)

Returns:

bits list or None if error

Return type:

list of bool or None

read_holding_registers(reg_addr, reg_nb=1)

Modbus function READ_HOLDING_REGISTERS (0x03)

Parameters:

• reg_addr (int) – register address (0 to 65535)
• reg_nb (int) – number of registers to read (1 to 125)

Returns:

registers list or None if fail

Return type:

list of int or None

read_input_registers(reg_addr, reg_nb=1)

Modbus function READ_INPUT_REGISTERS (0x04)

Parameters:

• reg_addr (int) – register address (0 to 65535)
• reg_nb (int) – number of registers to read (1 to 125)

Returns:

registers list or None if fail

Return type:

list of int or None

unit_id(unit_id=None)

Get or set unit ID field

Parameters:unit_id (int or None) – unit ID (0 to 255) or None for get value Returns:unit ID or None if set fail Return type:int or None

version()

Get package version

Returns:Current version of the package (like “0.0.1”) Return type:str

write_multiple_registers(reg_addr, regs_value)

Modbus function WRITE_MULTIPLE_REGISTERS (0x10)

Parameters:

• reg_addr (int) – registers address (0 to 65535)
• reg_value (list) – registers value to write

Returns:

True if write ok or None if fail

Return type:

bool or None

write_single_coil(bit_addr, bit_value)

Modbus function WRITE_SINGLE_COIL (0x05)

Parameters:

• bit_addr (int) – bit address (0 to 65535)
• bit_value (bool) – bit value to write

Returns:

True if write ok or None if fail

Return type:

bool or None

write_single_register(reg_addr, reg_value)

Modbus function WRITE_SINGLE_REGISTER (0x06)

Parameters:

• reg_addr (int) – register address (0 to 65535)
• reg_value (int) – register value to write

Returns:

True if write ok or None if fail

Return type:

bool or None