"""Modbus Device Controller. These are the device management handlers. They should be maintained in the server context and the various methods should be inserted in the correct locations. """ from __future__ import annotations __all__ = [ "ModbusPlusStatistics", "ModbusDeviceIdentification", "DeviceInformationFactory", ] import struct # pylint: disable=missing-type-doc from collections import OrderedDict from pymodbus.constants import INTERNAL_ERROR, DeviceInformation from pymodbus.events import ModbusEvent from pymodbus.utilities import dict_property # ---------------------------------------------------------------------------# # Modbus Plus Statistics # ---------------------------------------------------------------------------# class ModbusPlusStatistics: """This is used to maintain the current modbus plus statistics count. As of right now this is simply a stub to complete the modbus implementation. For more information, see the modbus implementation guide page 87. """ __data = OrderedDict( { "node_type_id": [0x00] * 2, # 00 "software_version_number": [0x00] * 2, # 01 "network_address": [0x00] * 2, # 02 "mac_state_variable": [0x00] * 2, # 03 "peer_status_code": [0x00] * 2, # 04 "token_pass_counter": [0x00] * 2, # 05 "token_rotation_time": [0x00] * 2, # 06 "program_master_token_failed": [0x00], # 07 hi "data_master_token_failed": [0x00], # 07 lo "program_master_token_owner": [0x00], # 08 hi "data_master_token_owner": [0x00], # 08 lo "program_slave_token_owner": [0x00], # 09 hi "data_slave_token_owner": [0x00], # 09 lo "data_slave_command_transfer": [0x00], # 10 hi "__unused_10_lowbit": [0x00], # 10 lo "program_slave_command_transfer": [0x00], # 11 hi "program_master_rsp_transfer": [0x00], # 11 lo "program_slave_auto_logout": [0x00], # 12 hi "program_master_connect_status": [0x00], # 12 lo "receive_buffer_dma_overrun": [0x00], # 13 hi "pretransmit_deferral_error": [0x00], # 13 lo "frame_size_error": [0x00], # 14 hi "repeated_command_received": [0x00], # 14 lo "receiver_alignment_error": [0x00], # 15 hi "receiver_collision_abort_error": [0x00], # 15 lo "bad_packet_length_error": [0x00], # 16 hi "receiver_crc_error": [0x00], # 16 lo "transmit_buffer_dma_underrun": [0x00], # 17 hi "bad_link_address_error": [0x00], # 17 lo "bad_mac_function_code_error": [0x00], # 18 hi "internal_packet_length_error": [0x00], # 18 lo "communication_failed_error": [0x00], # 19 hi "communication_retries": [0x00], # 19 lo "no_response_error": [0x00], # 20 hi "good_receive_packet": [0x00], # 20 lo "unexpected_path_error": [0x00], # 21 hi "exception_response_error": [0x00], # 21 lo "forgotten_transaction_error": [0x00], # 22 hi "unexpected_response_error": [0x00], # 22 lo "active_station_bit_map": [0x00] * 8, # 23-26 "token_station_bit_map": [0x00] * 8, # 27-30 "global_data_bit_map": [0x00] * 8, # 31-34 "receive_buffer_use_bit_map": [0x00] * 8, # 35-37 "data_master_output_path": [0x00] * 8, # 38-41 "data_slave_input_path": [0x00] * 8, # 42-45 "program_master_outptu_path": [0x00] * 8, # 46-49 "program_slave_input_path": [0x00] * 8, # 50-53 } ) def __init__(self): """Initialize the modbus plus statistics with the default information.""" self.reset() def __iter__(self): """Iterate over the statistics. :returns: An iterator of the modbus plus statistics """ return iter(self.__data.items()) def reset(self): """Clear all of the modbus plus statistics.""" for key in self.__data: self.__data[key] = [0x00] * len(self.__data[key]) def summary(self): """Return a summary of the modbus plus statistics. :returns: 54 16-bit words representing the status """ return iter(self.__data.values()) def encode(self): """Return a summary of the modbus plus statistics. :returns: 54 16-bit words representing the status """ total, values = [], sum(self.__data.values(), []) # noqa: RUF017 for i in range(0, len(values), 2): total.append((values[i] << 8) | values[i + 1]) return total # ---------------------------------------------------------------------------# # Device Information Control # ---------------------------------------------------------------------------# class ModbusDeviceIdentification: """This is used to supply the device identification. For the readDeviceIdentification function For more information read section 6.21 of the modbus application protocol. """ __data = { 0x00: "", # VendorName 0x01: "", # ProductCode 0x02: "", # MajorMinorRevision 0x03: "", # VendorUrl 0x04: "", # ProductName 0x05: "", # ModelName 0x06: "", # UserApplicationName 0x07: "", # reserved 0x08: "", # reserved # 0x80 -> 0xFF are privatek } __names = [ "VendorName", "ProductCode", "MajorMinorRevision", "VendorUrl", "ProductName", "ModelName", "UserApplicationName", ] def __init__(self, info=None, info_name=None): """Initialize the datastore with the elements you need. (note acceptable range is [0x00-0x06,0x80-0xFF] inclusive) :param info: A dictionary of {int:string} of values :param set: A dictionary of {name:string} of values """ if isinstance(info_name, dict): for key in info_name: inx = self.__names.index(key) self.__data[inx] = info_name[key] if isinstance(info, dict): for key in info: if (0x06 >= key >= 0x00) or (0xFF >= key >= 0x80): self.__data[key] = info[key] def __iter__(self): """Iterate over the device information. :returns: An iterator of the device information """ return iter(self.__data.items()) def summary(self): """Return a summary of the main items. :returns: An dictionary of the main items """ return dict(zip(self.__names, iter(self.__data.values()))) def update(self, value): """Update the values of this identity. using another identify as the value :param value: The value to copy values from """ self.__data.update(value) def __setitem__(self, key, value): """Access the device information. :param key: The register to set :param value: The new value for referenced register """ if key not in [0x07, 0x08]: self.__data[key] = value def __getitem__(self, key): """Access the device information. :param key: The register to read """ return self.__data.setdefault(key, "") def __str__(self): """Build a representation of the device. :returns: A string representation of the device """ return "DeviceIdentity" # -------------------------------------------------------------------------# # Properties # -------------------------------------------------------------------------# # fmt: off VendorName = dict_property(lambda s: s.__data, 0) # pylint: disable=protected-access ProductCode = dict_property(lambda s: s.__data, 1) # pylint: disable=protected-access MajorMinorRevision = dict_property(lambda s: s.__data, 2) # pylint: disable=protected-access VendorUrl = dict_property(lambda s: s.__data, 3) # pylint: disable=protected-access ProductName = dict_property(lambda s: s.__data, 4) # pylint: disable=protected-access ModelName = dict_property(lambda s: s.__data, 5) # pylint: disable=protected-access UserApplicationName = dict_property(lambda s: s.__data, 6) # pylint: disable=protected-access # fmt: on class DeviceInformationFactory: # pylint: disable=too-few-public-methods """This is a helper factory. That really just hides some of the complexity of processing the device information requests (function code 0x2b 0x0e). """ __lookup = { DeviceInformation.BASIC: lambda c, r, i: c.__gets( # pylint: disable=protected-access r, list(range(i, 0x03)) ), DeviceInformation.REGULAR: lambda c, r, i: c.__gets( # pylint: disable=protected-access r, list(range(i, 0x07)) if c.__get(r, i)[i] # pylint: disable=protected-access else list(range(0, 0x07)), ), DeviceInformation.EXTENDED: lambda c, r, i: c.__gets( # pylint: disable=protected-access r, [x for x in range(i, 0x100) if x not in range(0x07, 0x80)] if c.__get(r, i)[i] # pylint: disable=protected-access else [x for x in range(0, 0x100) if x not in range(0x07, 0x80)], ), DeviceInformation.SPECIFIC: lambda c, r, i: c.__get( # pylint: disable=protected-access r, i ), } @classmethod def get(cls, control, read_code=DeviceInformation.BASIC, object_id=0x00): """Get the requested device data from the system. :param control: The control block to pull data from :param read_code: The read code to process :param object_id: The specific object_id to read :returns: The requested data (id, length, value) """ identity = control.Identity return cls.__lookup[read_code](cls, identity, object_id) @classmethod def __get(cls, identity, object_id): # pylint: disable=unused-private-member """Read a single object_id from the device information. :param identity: The identity block to pull data from :param object_id: The specific object id to read :returns: The requested data (id, length, value) """ return {object_id: identity[object_id]} @classmethod def __gets(cls, identity, object_ids): # pylint: disable=unused-private-member """Read multiple object_ids from the device information. :param identity: The identity block to pull data from :param object_ids: The specific object ids to read :returns: The requested data (id, length, value) """ return {oid: identity[oid] for oid in object_ids if identity[oid]} def __init__(self): """Prohibit objects.""" raise RuntimeError(INTERNAL_ERROR) # ---------------------------------------------------------------------------# # Counters Handler # ---------------------------------------------------------------------------# class ModbusCountersHandler: """This is a helper class to simplify the properties for the counters. 0x0B 1 Return Bus Message Count Quantity of messages that the remote device has detected on the communications system since its last restart, clear counters operation, or power-up. Messages with bad CRC are not taken into account. 0x0C 2 Return Bus Communication Error Count Quantity of CRC errors encountered by the remote device since its last restart, clear counters operation, or power-up. In case of an error detected on the character level, (overrun, parity error), or in case of a message length < 3 bytes, the receiving device is not able to calculate the CRC. In such cases, this counter is also incremented. 0x0D 3 Return Slave Exception Error Count Quantity of MODBUS exception error detected by the remote device since its last restart, clear counters operation, or power-up. It comprises also the error detected in broadcast messages even if an exception message is not returned in this case. Exception errors are described and listed in "MODBUS Application Protocol Specification" document. 0xOE 4 Return Slave Message Count Quantity of messages addressed to the remote device, including broadcast messages, that the remote device has processed since its last restart, clear counters operation, or power-up. 0x0F 5 Return Slave No Response Count Quantity of messages received by the remote device for which it returned no response (neither a normal response nor an exception response), since its last restart, clear counters operation, or power-up. Then, this counter counts the number of broadcast messages it has received. 0x10 6 Return Slave NAK Count Quantity of messages addressed to the remote device for which it returned a Negative Acknowledge (NAK) exception response, since its last restart, clear counters operation, or power-up. Exception responses are described and listed in "MODBUS Application Protocol Specification" document. 0x11 7 Return Slave Busy Count Quantity of messages addressed to the remote device for which it returned a Slave Device Busy exception response, since its last restart, clear counters operation, or power-up. Exception responses are described and listed in "MODBUS Application Protocol Specification" document. 0x12 8 Return Bus Character Overrun Count Quantity of messages addressed to the remote device that it could not handle due to a character overrun condition, since its last restart, clear counters operation, or power-up. A character overrun is caused by data characters arriving at the port faster than they can. .. note:: I threw the event counter in here for convenience """ __data = {i: 0x0000 for i in range(9)} __names = [ "BusMessage", "BusCommunicationError", "SlaveExceptionError", "SlaveMessage", "SlaveNoResponse", "SlaveNAK", "SlaveBusy", "BusCharacterOverrun", ] def __iter__(self): """Iterate over the device counters. :returns: An iterator of the device counters """ return zip(self.__names, iter(self.__data.values())) def update(self, values): """Update the values of this identity. using another identify as the value :param values: The value to copy values from """ for k, v_item in iter(values.items()): v_item += self.__getattribute__( # pylint: disable=unnecessary-dunder-call k ) self.__setattr__(k, v_item) # pylint: disable=unnecessary-dunder-call def reset(self): """Clear all of the system counters.""" self.__data = {i: 0x0000 for i in range(9)} def summary(self): """Return a summary of the counters current status. :returns: A byte with each bit representing each counter """ count, result = 0x01, 0x00 for i in iter(self.__data.values()): if i != 0x00: # pylint: disable=compare-to-zero result |= count count <<= 1 return result # -------------------------------------------------------------------------# # Properties # -------------------------------------------------------------------------# # fmt: off BusMessage = dict_property(lambda s: s.__data, 0) # pylint: disable=protected-access BusCommunicationError = dict_property(lambda s: s.__data, 1) # pylint: disable=protected-access BusExceptionError = dict_property(lambda s: s.__data, 2) # pylint: disable=protected-access SlaveMessage = dict_property(lambda s: s.__data, 3) # pylint: disable=protected-access SlaveNoResponse = dict_property(lambda s: s.__data, 4) # pylint: disable=protected-access SlaveNAK = dict_property(lambda s: s.__data, 5) # pylint: disable=protected-access SlaveBusy = dict_property(lambda s: s.__data, 6) # pylint: disable=protected-access BusCharacterOverrun = dict_property(lambda s: s.__data, 7) # pylint: disable=protected-access Event = dict_property(lambda s: s.__data, 8) # pylint: disable=protected-access # fmt: on # ---------------------------------------------------------------------------# # Main server control block # ---------------------------------------------------------------------------# class ModbusControlBlock: """This is a global singleton that controls all system information. All activity should be logged here and all diagnostic requests should come from here. """ _mode = "ASCII" _diagnostic = [False] * 16 _listen_only = False _delimiter = b"\r" _counters = ModbusCountersHandler() _identity = ModbusDeviceIdentification() _plus = ModbusPlusStatistics() _events: list[ModbusEvent] = [] # -------------------------------------------------------------------------# # Magic # -------------------------------------------------------------------------# def __str__(self): """Build a representation of the control block. :returns: A string representation of the control block """ return "ModbusControl" def __iter__(self): """Iterate over the device counters. :returns: An iterator of the device counters """ return self._counters.__iter__() def __new__(cls): """Create a new instance.""" if "_inst" not in vars(cls): cls._inst = object.__new__(cls) return cls._inst # -------------------------------------------------------------------------# # Events # -------------------------------------------------------------------------# def addEvent(self, event: ModbusEvent): """Add a new event to the event log. :param event: A new event to add to the log """ self._events.insert(0, event) self._events = self._events[0:64] # chomp to 64 entries self.Counter.Event += 1 def getEvents(self): """Return an encoded collection of the event log. :returns: The encoded events packet """ events = [event.encode() for event in self._events] return b"".join(events) def clearEvents(self): """Clear the current list of events.""" self._events = [] # -------------------------------------------------------------------------# # Other Properties # -------------------------------------------------------------------------# Identity = property(lambda s: s._identity) Counter = property(lambda s: s._counters) Events = property(lambda s: s._events) Plus = property(lambda s: s._plus) def reset(self): """Clear all of the system counters and the diagnostic register.""" self._events = [] self._counters.reset() self._diagnostic = [False] * 16 # -------------------------------------------------------------------------# # Listen Properties # -------------------------------------------------------------------------# def _setListenOnly(self, value): """Toggle the listen only status. :param value: The value to set the listen status to """ self._listen_only = bool(value) ListenOnly = property(lambda s: s._listen_only, _setListenOnly) # -------------------------------------------------------------------------# # Mode Properties # -------------------------------------------------------------------------# def _setMode(self, mode): """Toggle the current serial mode. :param mode: The data transfer method in (RTU, ASCII) """ if mode in {"ASCII", "RTU"}: self._mode = mode Mode = property(lambda s: s._mode, _setMode) # -------------------------------------------------------------------------# # Delimiter Properties # -------------------------------------------------------------------------# def _setDelimiter(self, char): """Change the serial delimiter character. :param char: The new serial delimiter character """ if isinstance(char, str): self._delimiter = char.encode() if isinstance(char, bytes): self._delimiter = char elif isinstance(char, int): self._delimiter = struct.pack(">B", char) Delimiter = property(lambda s: s._delimiter, _setDelimiter) # -------------------------------------------------------------------------# # Diagnostic Properties # -------------------------------------------------------------------------# def setDiagnostic(self, mapping): """Set the value in the diagnostic register. :param mapping: Dictionary of key:value pairs to set """ for entry in iter(mapping.items()): if entry[0] >= 0 and entry[0] < len(self._diagnostic): self._diagnostic[entry[0]] = bool(entry[1]) def getDiagnostic(self, bit): """Get the value in the diagnostic register. :param bit: The bit to get :returns: The current value of the requested bit """ try: if bit and 0 <= bit < len(self._diagnostic): return self._diagnostic[bit] except Exception: # pylint: disable=broad-except return None return None def getDiagnosticRegister(self): """Get the entire diagnostic register. :returns: The diagnostic register collection """ return self._diagnostic