CHIRP

            d = _crypt(radio._enc_key_idx, d[4:])

            data = _crypt(radio._enc_key_idx, data)

    _enc_key_idx = 1

    def check_set_memory_immutable_policy(self, existing, new):

        if (self._airband[0] <= new.freq <= self._airband[1] and

                new.mode == 'AM'):

            # This is valid, so mark mode as immutable so it doesn't get

            # blocked, and let the radio override it during set.

            new.immutable.append('mode')

            existing.immutable = []

        elif existing.mode == 'AM' and new.mode in self.MODES:

            # If we're going from a forced-AM channel to some valid one,

            # clear immutable so we allow the change.

            try:

                existing.immutable.remove('mode')

            except ValueError:

                pass

        super().check_set_memory_immutable_policy(existing, new)

@directory.register

class UV18ProMaxGPS(UV17Pro):

    VENDOR = "Baofeng"

    MODEL = "UV-18ProMAXGPS"

    _enc_key_idx = 6 # "RVB " key used

    _has_support_for_banknames = True # Yes

    _has_workmode_support = True # No idea

    _magic = MSTRING_UV17PROGPS # ANS: 0x06 (ACK)

    _magics = [(b"\x46", 16),

                # ANS: "\x016\x01t\x04\x00\x05 \x02\x00\x02`\x01\x03P\x03"

                #      (\x01\x03 may be SW version 1.03)

               (b"\x4d", 7),  # A: UV18PRO

               (b"SEND\x23\x06\x04\x11\x03\x0f\x09\x09\x06" +

                b"\x0e\x0f\x03\x09\x08\x02\x01\x06\x11\x12\x0e\x00", 1)]

                # 21 Bytes after SEND seem to be random, ANS: 0x06

    _has_when_to_send_aniid = False

    _vfoscan = True    # No idea

    _has_gps = True    # Yes

    _has_voxsw = True  # No idea

    _has_pilot_tone = True # No idea

    _has_send_id_delay = True # No idea

    _has_skey2_short = True # No idea

    VALID_BANDS = [UV17Pro._airband, UV17Pro._vhf_range, UV17Pro._vhf2_range,

                   UV17Pro._uhf_range, UV17Pro._uhf2_range]