Each protocol object is callable, and accepts a list of raw input strings, and returns a list of parsed Message objects. The data_bytes field will contain a list of integers, corresponding to all relevant data returned by the command.

Note: Message.data_bytes does not refer to the full data field of a message, but rather a subset of this field. Things like Mode/PID/PCI bytes are removed. However, Frame.data_bytes DOES include the full data field (per-spec), for each frame.

For example, these are the resultant Message.data_bytes fields for some single frame messages:

A CAN Message:
7E8 06 41 00 BE 7F B8 13
             [  data   ]

A J1850 Message:
48 6B 10 41 00 BE 7F B8 13 FF
               [  data   ]

All protocol objects must implement two functions:

Recieves a single frame (in string form), and is responsible for parsing and returning a new Frame object. If the frame is invalid, or the parse fails, this function should return None, and the frame will be dropped.

Recieves a list of Frames, and is responsible for assembling them into a finished Message object. This is where multi-line responses are assembled, and the final Message.data_bytes field is filled. If the message is found to be invalid, this function should return None, and the entire message will be dropped.

Protocol
    LegacyProtocol
        SAE_J1850_PWM
        SAE_J1850_VPM
        ISO_9141_2
        ISO_14230_4_5baud
        ISO_14230_4_fast
    CANProtocol
        ISO_15765_4_11bit_500k
        ISO_15765_4_29bit_500k
        ISO_15765_4_11bit_250k
        ISO_15765_4_29bit_250k
        SAE_J1939