#!/usr/bin/env python3
"""Used to Reverse/Test ELM protocol auto detect and OBD message response without a car."""
import os
import sys
import struct
import binascii
import time
import threading
from collections import deque
from panda import Panda
[docs]
def lin_checksum(dat):
return sum(dat) % 0x100
[docs]
class ELMCarSimulator():
def __init__(self, sn, silent=False, can_kbaud=500,
can=True, can11b=True, can29b=True,
lin=True):
self.__p = Panda(sn if sn else Panda.list()[0])
self.__on = True
self.__stop = False
self.__silent = silent
self.__lin_timer = None
self.__lin_active = False
self.__lin_enable = lin
self.__lin_monitor_thread = threading.Thread(target=self.__lin_monitor)
self.__can_multipart_data = None
self.__can_kbaud = can_kbaud
self.__can_extra_noise_msgs = deque()
self.__can_enable = can
self.__can11b = can11b
self.__can29b = can29b
self.__can_monitor_thread = threading.Thread(target=self.__can_monitor)
@property
def panda(self):
return self.__p
[docs]
def stop(self):
if self.__lin_timer:
self.__lin_timer.cancel()
self.__lin_timeout_handler()
self.__stop = True
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def join(self):
if self.__lin_monitor_thread.is_alive():
self.__lin_monitor_thread.join()
if self.__can_monitor_thread.is_alive():
self.__can_monitor_thread.join()
if self.__p:
print("closing handle")
self.__p.close()
[docs]
def set_enable(self, on):
self.__on = on
[docs]
def start(self):
self.panda.set_safety_mode(Panda.SAFETY_ALLOUTPUT)
if self.__lin_enable:
self.__lin_monitor_thread.start()
if self.__can_enable:
self.__can_monitor_thread.start()
#########################
# CAN related functions #
#########################
def __can_monitor(self):
print("STARTING CAN THREAD")
self.panda.set_can_speed_kbps(0, self.__can_kbaud)
self.panda.can_recv() # Toss whatever was already there
while not self.__stop:
for address, ts, data, src in self.panda.can_recv():
if self.__on and src == 0 and len(data) == 8 and data[0] >= 2:
if not self.__silent:
print("Processing CAN message", src, hex(address), binascii.hexlify(data))
self.__can_process_msg(data[1], data[2], address, ts, data, src)
elif not self.__silent:
print("Rejecting CAN message", src, hex(address), binascii.hexlify(data))
[docs]
def can_mode_11b(self):
self.__can11b = True
self.__can29b = False
[docs]
def can_mode_29b(self):
self.__can11b = False
self.__can29b = True
[docs]
def can_mode_11b_29b(self):
self.__can11b = True
self.__can29b = True
[docs]
def change_can_baud(self, kbaud):
self.__can_kbaud = kbaud
self.panda.set_can_speed_kbps(0, self.__can_kbaud)
def _can_send(self, addr, msg):
if not self.__silent:
print(" CAN Reply (%x)" % addr, binascii.hexlify(msg))
self.panda.can_send(addr, msg + b'\x00' * (8 - len(msg)), 0)
if self.__can_extra_noise_msgs:
noise = self.__can_extra_noise_msgs.popleft()
self.panda.can_send(noise[0] if noise[0] is not None else addr,
noise[1] + b'\x00' * (8 - len(noise[1])), 0)
def _can_addr_matches(self, addr):
if self.__can11b and (addr == 0x7DF or (addr & 0x7F8) == 0x7E0):
return True
if self.__can29b and (addr == 0x18db33f1 or (addr & 0x1FFF00FF) == 0x18da00f1):
return True
return False
def __can_process_msg(self, mode, pid, address, ts, data, src):
if not self.__silent:
print("CAN MSG", binascii.hexlify(data[1:1 + data[0]]),
"Addr:", hex(address), "Mode:", hex(mode)[2:].zfill(2),
"PID:", hex(pid)[2:].zfill(2), "canLen:", len(data),
binascii.hexlify(data))
if self._can_addr_matches(address) and len(data) == 8:
outmsg = None
if data[:3] == b'\x30\x00\x00' and len(self.__can_multipart_data):
if not self.__silent:
print("Request for more data")
outaddr = 0x7E8 if address == 0x7DF or address == 0x7E0 else 0x18DAF110
msgnum = 1
while(self.__can_multipart_data):
datalen = min(7, len(self.__can_multipart_data))
msgpiece = struct.pack("B", 0x20 | msgnum) + self.__can_multipart_data[:datalen]
self._can_send(outaddr, msgpiece)
self.__can_multipart_data = self.__can_multipart_data[7:]
msgnum = (msgnum + 1) % 0x10
time.sleep(0.01)
else:
outmsg = self._process_obd(mode, pid)
if outmsg:
outaddr = 0x7E8 if address == 0x7DF or address == 0x7E0 else 0x18DAF110
if len(outmsg) <= 5:
self._can_send(outaddr,
struct.pack("BBB", len(outmsg) + 2, 0x40 | data[1], pid) + outmsg)
else:
first_msg_len = min(3, len(outmsg) % 7)
payload_len = len(outmsg) + 3
msgpiece = struct.pack("BBBBB", 0x10 | ((payload_len >> 8) & 0xF),
payload_len & 0xFF,
0x40 | data[1], pid, 1) + outmsg[:first_msg_len]
self._can_send(outaddr, msgpiece)
self.__can_multipart_data = outmsg[first_msg_len:]
#########################
# General OBD functions #
#########################
def _process_obd(self, mode, pid):
if mode == 0x01: # Mode: Show current data
if pid == 0x00: # List supported things
return b"\xff\xff\xff\xfe" # b"\xBE\x1F\xB8\x10" #Bitfield, random features
elif pid == 0x01: # Monitor Status since DTC cleared
return b"\x00\x00\x00\x00" # Bitfield, random features
elif pid == 0x04: # Calculated engine load
return b"\x2f"
elif pid == 0x05: # Engine coolant temperature
return b"\x3c"
elif pid == 0x0B: # Intake manifold absolute pressure
return b"\x90"
elif pid == 0x0C: # Engine RPM
return b"\x1A\xF8"
elif pid == 0x0D: # Vehicle Speed
return b"\x53"
elif pid == 0x10: # MAF air flow rate
return b"\x01\xA0"
elif pid == 0x11: # Throttle Position
return b"\x90"
elif pid == 0x33: # Absolute Barometric Pressure
return b"\x90"
elif mode == 0x09: # Mode: Request vehicle information
if pid == 0x02: # Show VIN
return b"1D4GP00R55B123456"
if pid == 0xFC: # test long multi message. Ligned up for LIN responses
return b''.join(struct.pack(">BBH", 0xAA, 0xAA, num + 1) for num in range(80))
if pid == 0xFD: # test long multi message
parts = (b'\xAA\xAA\xAA' + struct.pack(">I", num) for num in range(80))
return b'\xAA\xAA\xAA' + b''.join(parts)
if pid == 0xFE: # test very long multi message
parts = (b'\xAA\xAA\xAA' + struct.pack(">I", num) for num in range(584))
return b'\xAA\xAA\xAA' + b''.join(parts) + b'\xAA'
if pid == 0xFF:
return b'\xAA\x00\x00' + \
b"".join((b'\xAA' * 5) + struct.pack(">H", num + 1) for num in range(584))
#return b"\xAA"*100#(0xFFF-3)
if __name__ == "__main__":
serial = os.getenv("SERIAL") if os.getenv("SERIAL") else None
kbaud = int(os.getenv("CANKBAUD")) if os.getenv("CANKBAUD") else 500 # type: ignore
bitwidth = int(os.getenv("CANBITWIDTH")) if os.getenv("CANBITWIDTH") else 0 # type: ignore
canenable = bool(int(os.getenv("CANENABLE"))) if os.getenv("CANENABLE") else True # type: ignore
linenable = bool(int(os.getenv("LINENABLE"))) if os.getenv("LINENABLE") else True # type: ignore
sim = ELMCarSimulator(serial, can_kbaud=kbaud, can=canenable, lin=linenable)
if(bitwidth == 0):
sim.can_mode_11b_29b()
if(bitwidth == 11):
sim.can_mode_11b()
if(bitwidth == 29):
sim.can_mode_29b()
import signal
def signal_handler(signal, frame):
print('\nShutting down simulator')
sim.stop()
sim.join()
sys.exit(0)
signal.signal(signal.SIGINT, signal_handler)
sim.start()
signal.pause()