主要是通过python-can模块与pcan等支持的硬件通讯，uds协议层使用udsoncan模块和can-isotp模块实现uds诊断。

1、模块安装及相关文档

        Python-can模块

        pip install python-can

        相关文档链接：Installation - python-can 4.1.0 documentation

        udsoncan模块

        pip install udsoncan

        相关文档链接：Python implementation of UDS standard (ISO-14229) — udsoncan 0 documentation

        can-isotp模块

        pip install can-isotp

        相关文档链接：Python support for IsoTP Transport protocol (ISO-15765) — isotp 0 documentation

2、相关示例

        下面示例展示了如何将PythonIsoTpConnection与Vector接口一起使用。

from can.interfaces.vector import VectorBusfrom udsoncan.connections import PythonIsoTpConnectionfrom udsoncan.client import Clientimport isotp# Refer to isotp documentation for full details about parametersisotp_params = {   'stmin' : 32,                          # Will request the sender to wait 32ms between consecutive frame. 0-127ms or 100-900ns with values from 0xF1-0xF9   'blocksize' : 8,                       # Request the sender to send 8 consecutives frames before sending a new flow control message   'wftmax' : 0,                          # Number of wait frame allowed before triggering an error   'tx_data_length' : 8,                  # Link layer (CAN layer) works with 8 byte payload (CAN 2.0)   'tx_data_min_length' : None,           # Minimum length of CAN messages. When different from None, messages are padded to meet this length. Works with CAN 2.0 and CAN FD.   'tx_padding' : 0,                      # Will pad all transmitted CAN messages with byte 0x00.   'rx_flowcontrol_timeout' : 1000,       # Triggers a timeout if a flow control is awaited for more than 1000 milliseconds   'rx_consecutive_frame_timeout' : 1000, # Triggers a timeout if a consecutive frame is awaited for more than 1000 milliseconds   'squash_stmin_requirement' : False,    # When sending, respect the stmin requirement of the receiver. If set to True, Go as fast as possible.   'max_frame_size' : 4095                # Limit the size of receive frame.}bus = VectorBus(channel=0, bitrate=500000)              # Link Layer (CAN protocol)tp_addr = isotp.Address(isotp.AddressingMode.NORMal_11bits, txid=0x123, rxid=0x456) # Network layer addressing schemestack = isotp.CanStack(bus=bus, address=tp_addr, params=isotp_params)               # Network/Transport layer (IsoTP protocol)stack.set_sleep_timing(0, 0)# Speed First (do not sleep)conn = PythonIsoTpConnection(stack)                     # interface between Application and Transport layerwith Client(conn, request_timeout=1) as client:         # Application layer (UDS protocol)   client.change_session(1)   # ...

        其他uds服务相关使用示例：

import udsoncanfrom udsoncan.connections import IsoTPSocketConnectionfrom udsoncan.client import Clientfrom udsoncan.exceptions import *from udsoncan.services import *udsoncan.setup_logging()conn = IsoTPSocketConnection('can0', rxid=0x123, txid=0x456)with Client(conn,  request_timeout=2, config=MyCar.config) as client:   try:      client.change_session(DiagnosticSessionControl.Session.extendedDiagnosticSession)  # integer with value of 3      client.unlock_security_access(MyCar.debug_level)   # Fictive security level. Integer coming from fictive lib, let's say its value is 5      client.write_data_by_identifier(udsoncan.DataIdentifier.VIN, 'ABC123456789')       # Standard ID for VIN is 0xF190. Codec is set in the client configuration      print('Vehicle Identification Number successfully changed.')      client.ecu_reset(ECUReset.ResetType.hardReset)  # HardReset = 0x01   except NegativeResponseException as e:      print('Server refused our request for service %s with code "%s" (0x%02x)' % (e.response.service.get_name(), e.response.code_name, e.response.code))   except InvalidResponseException, UnexpectedResponseException as e:      print('Server sent an invalid payload : %s' % e.response.original_payload)

安全算法示例，需要实现myalgo函数，并且uds的configs中的security_algo配置为myalgo，同时配置security_algo_params。

def myalgo(level, seed, params):"""Builds the security key to unlock a security level. Returns the seed xor'ed with pre-shared key."""   output_key = bytearray(seed)   xorkey = bytearray(params['xorkey'])   for i in range(len(seed)):      output_key[i] = seed[i] ^ xorkey[i%len(xorkey)]   return bytes(output_key)client.config['security_algo'] = myalgoclient.config['security_algo_params'] = dict(xorkey=b'\x12\x34\x56\x78')

使用DID配置配置客户端，并使用ReadDataByIdentifier请求服务器

import udsoncanfrom udsoncan.connections import IsoTPSocketConnectionfrom udsoncan.client import Clientimport udsoncan.configsimport structclass MyCustomCodecThatShiftBy4(udsoncan.DidCodec):   def encode(self, val):      val = (val << 4) & 0xFFFFFFFF # Do some stuff      return struct.pack('> 4                        # Do some stuff (reversed)   def __len__(self):      return 4    # encoded payload is 4 byte long.config = dict(udsoncan.configs.default_client_config)config['data_identifiers'] = {   0x1234 : MyCustomCodecThatShiftBy4,    # Uses own custom defined codec. Giving the class is ok   0x1235 : MyCustomCodecThatShiftBy4(),  # Same as 0x1234, giving an instance is good also   0xF190 : udsoncan.AsciiCodec(15)       # Codec that read ASCII string. We must tell the length of the string   }# IsoTPSocketconnection only works with SocketCAN under linux. Use another connection if needed.conn = IsoTPSocketConnection('vcan0', rxid=0x123, txid=0x456)with Client(conn,  request_timeout=2, config=config) as client:   response = client.read_data_by_identifier([0xF190])   print(response.service_data.values[0xF190]) # This is a dict of DID:Value   # Or, if a single DID is expected, a shortcut to read the value of the first DID   vin = client.read_data_by_identifier_first(0xF190)   print(vin)  # 'ABCDE0123456789' (15 chars)

来源地址：https://blog.csdn.net/qq_45303968/article/details/126251064