`factory` — Request/Response Decoders¶

API Documentation¶

Modbus Request/Response Decoder Factories¶

The following factories make it easy to decode request/response messages. To add a new request/response pair to be decodeable by the library, simply add them to the respective function lookup table (order doesn’t matter, but it does help keep things organized).

Regardless of how many functions are added to the lookup, O(1) behavior is kept as a result of a pre-computed lookup dictionary.

class pymodbus.factory.ServerDecoder¶

Request Message Factory (Server)

To add more implemented functions, simply add them to the list

__init__()¶: Initializes the client lookup tables

_helper(data)¶

This factory is used to generate the correct request object from a valid request packet. This decodes from a list of the currently implemented request types.

Parameters:	data – The request packet to decode
Returns:	The decoded request or illegal function request object

decode(message)¶

Wrapper to decode a request packet

Parameters:	message – The raw modbus request packet
Returns:	The decoded modbus message or None if error

lookupPduClass(function_code)¶

Use function_code to determine the class of the PDU.

Parameters:	function_code – The function code specified in a frame.
Returns:	The class of the PDU that has a matching function_code.

class pymodbus.factory.ClientDecoder¶

Response Message Factory (Client)