Cpppo is used to create event-driven state machines which consume a stream
of input and generate a series of state changes, or an indication that no
progress is possible due to (for example) exhaustion of input symbols.
This is useful for creating parsers for complex grammars describing
languages, including binary computer protocols.
An example included with cpppo is an implementation of a subset of the
EtherNet/IP CIP language used by some industrial control equipment, such as
Rockwell's ControlLogix Controllers. The cpppo.server.enip package can be used
to create Python programs which can parse requests in this protocol (eg. as a
server, to implement something like a simulated Controller) or originate
requests in this protocol (eg. as a client, sending commands to a Controller).
In addition, the ability to read, write and poll remote PLCs of
various types including Modbus/TCP is provided.