Innovenergy_trunk/firmware/opt/innovenergy/scripts/reset-bms

#!/usr/bin/python2 -u
# coding=utf-8
from os import system
from pymodbus.client.sync import ModbusSerialClient as Modbus
from pymodbus.exceptions import ModbusIOException
from sys import argv, exit

# trick the pycharm type-checker into thinking Callable is in scope, not used at runtime
# noinspection PyUnreachableCode
if False:
    from typing import List, Optional


RESET_REGISTER = 0x2087
FIRMWARE_VERSION_REGISTER = 1054
SERIAL_STARTER_DIR = '/opt/victronenergy/serial-starter/'


class LockTTY(object):

    def __init__(self, tty):
        # type: (str) -> None
        self.tty = tty

    def __enter__(self):
        system(SERIAL_STARTER_DIR + 'stop-tty.sh ' + self.tty)
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        system(SERIAL_STARTER_DIR + 'start-tty.sh ' + self.tty)


def init_modbus(tty):
    # type: (str) -> Modbus

    return Modbus(
        port='/dev/' + tty,
        method='rtu',
        baudrate=115200,
        stopbits=1,
        bytesize=8,
        timeout=1,  # seconds
        parity='O')


def reset_bms(modbus, slave_id):
    # type: (Modbus, int) -> bool

    print ('resetting BMS...')

    result = modbus.write_registers(RESET_REGISTER, [1], unit=slave_id)

    # expecting a ModbusIOException (timeout)
    # BMS can no longer reply because it is already reset
    return isinstance(result, ModbusIOException)


def identify_battery(modbus, slave_id):
    # type: (Modbus, int) -> bool

    target = 'battery #' + str(slave_id) + ' at ' + modbus.port

    try:

        print(('contacting ' + target + ' ...'))

        response = modbus.read_input_registers(address=FIRMWARE_VERSION_REGISTER, count=1, unit=slave_id)
        fw = '{0:0>4X}'.format(response.registers[0])

        print(('found battery with firmware ' + fw))

        return True

    except:
        print(('failed to communicate with ' + target + ' !'))
        return False


def is_int(value):
    # type: (str) -> bool
    try:
        _ = int(value)
        return True
    except ValueError:
        return False


def print_usage():
    print(('Usage:   ' + __file__ + ' <slave id> <serial device>'))
    print(('Example: ' + __file__ + ' 2 ttyUSB0'))
    print ('')
    print ('You can omit the "ttyUSB" prefix of the serial device:')
    print(('  ' + __file__ + ' 2 0'))
    print ('')
    print ('You can omit the serial device entirely when the "com.victronenergy.battery.<serial device>" service is running:')
    print(('  ' + __file__ + ' 2'))
    print ('')


def get_tty_from_battery_service_name():
    # type: () -> Optional[str]

    import dbus
    bus = dbus.SystemBus()

    tty = (
        name.split('.')[-1]
        for name in bus.list_names()
        if name.startswith('com.victronenergy.battery.')
    )

    return next(tty, None)


def parse_tty(tty):
    # type: (Optional[str]) -> str

    if tty is None:
        return get_tty_from_battery_service_name()

    if is_int(tty):
        return 'ttyUSB' + argv[1]
    else:
        return tty


def parse_cmdline_args(argv):
    # type: (List[str]) -> (str, int)

    slave_id = element_at_or_none(argv, 0)
    tty = parse_tty(element_at_or_none(argv, 1))

    if slave_id is None or tty is None:
        print_usage()
        exit(2)

    return tty, int(slave_id)


def element_at_or_none(lst, index):
    return next(iter(lst[index:]), None)


def main(argv):
    # type: (List[str]) -> ()

    tty, slave_id = parse_cmdline_args(argv)

    with LockTTY(tty), init_modbus(tty) as modbus:

        if identify_battery(modbus, slave_id) and reset_bms(modbus, slave_id):
            print('SUCCESS')
            exit(0)
        else:
            print('FAILURE')
            exit(1)


main(argv[1:])