Source code for panda.python.isotp

import binascii
import time

DEBUG = False

[docs] def msg(x): if DEBUG: print("S:", binascii.hexlify(x)) assert len(x) <= 7 ret = bytes([len(x)]) + x return ret.ljust(8, b"\x00")
kmsgs = []
[docs] def recv(panda, cnt, addr, nbus): global kmsgs ret = [] while len(ret) < cnt: kmsgs += panda.can_recv() nmsgs = [] for ids, ts, dat, bus in kmsgs: if ids == addr and bus == nbus and len(ret) < cnt: ret.append(dat) else: # leave around nmsgs.append((ids, ts, dat, bus)) kmsgs = nmsgs[-256:] return ret
[docs] def isotp_recv_subaddr(panda, addr, bus, sendaddr, subaddr): msg = recv(panda, 1, addr, bus)[0] # TODO: handle other subaddr also communicating assert msg[0] == subaddr if msg[1] & 0xf0 == 0x10: # first tlen = ((msg[1] & 0xf) << 8) | msg[2] dat = msg[3:] # 0 block size? CONTINUE = bytes([subaddr]) + b"\x30" + b"\x00" * 6 panda.can_send(sendaddr, CONTINUE, bus) idx = 1 for mm in recv(panda, (tlen - len(dat) + 5) // 6, addr, bus): assert mm[0] == subaddr assert mm[1] == (0x20 | (idx & 0xF)) dat += mm[2:] idx += 1 elif msg[1] & 0xf0 == 0x00: # single tlen = msg[1] & 0xf dat = msg[2:] else: print(binascii.hexlify(msg)) raise AssertionError return dat[0:tlen]
# **** import below this line ****
[docs] def isotp_send(panda, x, addr, bus=0, recvaddr=None, subaddr=None, rate=None): if recvaddr is None: recvaddr = addr + 8 if len(x) <= 7 and subaddr is None: panda.can_send(addr, msg(x), bus) elif len(x) <= 6 and subaddr is not None: panda.can_send(addr, bytes([subaddr]) + msg(x)[0:7], bus) else: if subaddr: ss = bytes([subaddr, 0x10 + (len(x) >> 8), len(x) & 0xFF]) + x[0:5] x = x[5:] else: ss = bytes([0x10 + (len(x) >> 8), len(x) & 0xFF]) + x[0:6] x = x[6:] idx = 1 sends = [] while len(x) > 0: if subaddr: sends.append((bytes([subaddr, 0x20 + (idx & 0xF)]) + x[0:6]).ljust(8, b"\x00")) x = x[6:] else: sends.append((bytes([0x20 + (idx & 0xF)]) + x[0:7]).ljust(8, b"\x00")) x = x[7:] idx += 1 # actually send panda.can_send(addr, ss, bus) rr = recv(panda, 1, recvaddr, bus)[0] if rr.find(b"\x30\x01") != -1: for s in sends[:-1]: panda.can_send(addr, s, 0) rr = recv(panda, 1, recvaddr, bus)[0] panda.can_send(addr, sends[-1], 0) else: if rate is None: panda.can_send_many([(addr, None, s, bus) for s in sends]) else: for dat in sends: panda.can_send(addr, dat, bus) time.sleep(rate)
[docs] def isotp_recv(panda, addr, bus=0, sendaddr=None, subaddr=None): if sendaddr is None: sendaddr = addr - 8 if subaddr is not None: dat = isotp_recv_subaddr(panda, addr, bus, sendaddr, subaddr) else: msg = recv(panda, 1, addr, bus)[0] if msg[0] & 0xf0 == 0x10: # first tlen = ((msg[0] & 0xf) << 8) | msg[1] dat = msg[2:] # 0 block size? CONTINUE = b"\x30" + b"\x00" * 7 panda.can_send(sendaddr, CONTINUE, bus) idx = 1 for mm in recv(panda, (tlen - len(dat) + 6) // 7, addr, bus): assert mm[0] == (0x20 | (idx & 0xF)) dat += mm[1:] idx += 1 elif msg[0] & 0xf0 == 0x00: # single tlen = msg[0] & 0xf dat = msg[1:] else: raise AssertionError dat = dat[0:tlen] if DEBUG: print("R:", binascii.hexlify(dat)) return dat