Communication between end device to nano gateway

Hi guys,
i’m newbie in LoRaWAN network configuration.
I need to get an end device to communicate with a nanogateway, both are lopy4 boards.
On the TTN server I have registered both the end device and the nanogateway. The nanogateway is correctly registered and online but the end device is not online.
For the authentication of the end device I have chosen the ABP method. If I send packets from the end device, I do not see any packets received in the logs of the nanogateway.
These are the codes used for the nanogateway:

config

#!/usr/bin/env python
#
# Copyright (c) 2019, Pycom Limited.
#
# This software is licensed under the GNU GPL version 3 or any
# later version, with permitted additional terms. For more information
# see the Pycom Licence v1.0 document supplied with this file, or
# available at https://www.pycom.io/opensource/licensing
#

""" LoPy LoRaWAN Nano Gateway configuration options """

import machine
import ubinascii

WIFI_MAC = ubinascii.hexlify(machine.unique_id()).upper()
# Set  the Gateway ID to be the first 3 bytes of MAC address + 'FFFE' + last 3 bytes of MAC address
GATEWAY_ID = WIFI_MAC[:6] + "FFFE" + WIFI_MAC[6:12]

SERVER = 'eu1.cloud.thethings.network'
PORT = 1700

NTP = "pool.ntp.org"
NTP_PERIOD_S = 3600

WIFI_SSID = '*********'
WIFI_PASS = '*******'

# for EU868
LORA_FREQUENCY = 868100000
LORA_GW_DR = "SF7BW125" # DR_5
LORA_NODE_DR = 5

# for US915
# LORA_FREQUENCY = 903900000
# LORA_GW_DR = "SF10BW125" # DR_0
# LORA_NODE_DR = 0

main

""" LoPy LoRaWAN Nano Gateway example usage """
# Acknowledgement:
# Thanks to robert-hh for providing us with an updated, more stable example for the nanogateway 

# disable heartbeat
from pycom import heartbeat
heartbeat(False)
print ("Heartbeat off")


import utime
from machine import RTC
rtc = RTC()
rtc.ntp_sync("pool.ntp.org")
utime.sleep_ms(750)
t = rtc.now()
with open("bootlog.txt", "a") as f:
   f.write(repr(utime.time()) + " " + repr(t) + "\n")

def reload(mod):
    import sys
    mod_name = mod.__name__
    del sys.modules[mod_name]
    return __import__(mod_name)

from machine import reset

""" LoPy LoRaWAN Nano Gateway example usage """

import config
from nanogateway import NanoGateway

if True: #__name__ == '__main__':
    nanogw = NanoGateway(
        id=config.GATEWAY_ID,
        frequency=config.LORA_FREQUENCY,
        datarate=config.LORA_GW_DR,
        ssid=config.WIFI_SSID,
        password=config.WIFI_PASS,
        server=config.SERVER,
        port=config.PORT,
        ntp_server=config.NTP,
        ntp_period=config.NTP_PERIOD_S
        )
    
    nanogw.start()
    #nanogw._log('You may now press ENTER to enter the REPL')
    #input()

nanogateway

""" LoPy LoRaWAN Nano Gateway. Can be used for both EU868 and US915. """

import errno
import machine
import ubinascii
import ujson
import uos
import usocket
import utime
import _thread
import gc
from micropython import const
from network import LoRa
from network import WLAN
from machine import Timer
from machine import WDT

PROTOCOL_VERSION = const(2)

PUSH_DATA = const(0)
PUSH_ACK = const(1)
PULL_DATA = const(2)
PULL_ACK = const(4)
PULL_RESP = const(3)

TX_ERR_NONE = 'NONE'
TX_ERR_TOO_LATE = 'TOO_LATE'
TX_ERR_TOO_EARLY = 'TOO_EARLY'
TX_ERR_COLLISION_PACKET = 'COLLISION_PACKET'
TX_ERR_COLLISION_BEACON = 'COLLISION_BEACON'
TX_ERR_TX_FREQ = 'TX_FREQ'
TX_ERR_TX_POWER = 'TX_POWER'
TX_ERR_GPS_UNLOCKED = 'GPS_UNLOCKED'

UDP_THREAD_CYCLE_MS = const(10)
WDT_TIMEOUT = const(120)


STAT_PK = {
    'stat': {
        'time': '',
        'lati': 0,
        'long': 0,
        'alti': 0,
        'rxnb': 0,
        'rxok': 0,
        'rxfw': 0,
        'ackr': 100.0,
        'dwnb': 0,
        'txnb': 0
    }
}

RX_PK = {
    'rxpk': [{
        'time': '',
        'tmst': 0,
        'chan': 0,
        'rfch': 0,
        'freq': 0,
        'stat': 1,
        'modu': 'LORA',
        'datr': '',
        'codr': '4/5',
        'rssi': 0,
        'lsnr': 0,
        'size': 0,
        'data': ''
    }]
}

TX_ACK_PK = {
    'txpk_ack': {
        'error': ''
    }
}


class NanoGateway:
    """
    Nano gateway class, set up by default for use with TTN, but can be configured
    for any other network supporting the Semtech Packet Forwarder.
    Only required configuration is wifi_ssid and wifi_password which are used for
    connecting to the Internet.
    """

    def __init__(self, id, frequency, datarate, ssid, password, server, port, ntp_server='pool.ntp.org', ntp_period=3600):
        self.id = id
        self.server = server
        self.port = port

        self.frequency = frequency
        self.datarate = datarate

        self.ssid = ssid
        self.password = password

        self.ntp_server = ntp_server
        self.ntp_period = ntp_period

        self.server_ip = None

        self.rxnb = 0
        self.rxok = 0
        self.rxfw = 0
        self.dwnb = 0
        self.txnb = 0

        self.sf = self._dr_to_sf(self.datarate)
        self.bw = self._dr_to_bw(self.datarate)

        self.stat_alarm = None
        self.pull_alarm = None
        self.uplink_alarm = None

        self.wlan = None
        self.sock = None
        self.udp_stop = False
        self.udp_lock = _thread.allocate_lock()

        self.lora = None
        self.lora_sock = None

        self.rtc = machine.RTC()

        self.watchdog = WDT(timeout=10000)

    def start(self):
        """
        Starts the LoRaWAN nano gateway.
        """

        self._log('Starting LoRaWAN nano gateway with id: {}', self.id)

        # setup WiFi as a station and connect
        self.wlan = WLAN(mode=WLAN.STA)
        self._connect_to_wifi()
        self.watchdog.feed()
        # get a time sync
        self._log('Syncing time with {} ...', self.ntp_server)
        self.rtc.ntp_sync(self.ntp_server, update_period=self.ntp_period)
        while not self.rtc.synced():
            utime.sleep_ms(50)
            self.watchdog.feed()
        self._log("RTC NTP sync complete")
        self.watchdog.feed()
        # get the server IP and create an UDP socket
        self.server_ip = usocket.getaddrinfo(self.server, self.port)[0][-1]
        self._log('Opening UDP socket to {} ({}) port {}...', self.server, self.server_ip[0], self.server_ip[1])
        self.sock = usocket.socket(usocket.AF_INET, usocket.SOCK_DGRAM, usocket.IPPROTO_UDP)
        self.sock.setsockopt(usocket.SOL_SOCKET, usocket.SO_REUSEADDR, 1)
        self.sock.setblocking(False)

        # push the first time immediatelly
        self._push_data(self._make_stat_packet())

        # create the alarms
        self.stat_alarm = Timer.Alarm(handler=lambda t: self._push_data(self._make_stat_packet()), s=60, periodic=True)
        self.pull_alarm = Timer.Alarm(handler=lambda u: self._pull_data(), s=25, periodic=True)

        # start the watchdog
        self.watchdog.feed()
        utime.sleep(1)
        self._log("Watchdog started")

        # start the UDP receive thread
        self.udp_stop = False
        _thread.start_new_thread(self._udp_thread, ())
        self.watchdog.feed()
        # initialize the LoRa radio in LORA mode
        self._log('Setting up the LoRa radio at {} Mhz using {}', self._freq_to_float(self.frequency), self.datarate)
        self.lora = LoRa(
            mode=LoRa.LORA,
            region=LoRa.EU868,
            frequency=self.frequency,
            bandwidth=self.bw,
            sf=self.sf,
            preamble=8,
            coding_rate=LoRa.CODING_4_5,
            tx_iq=True
        )

        # create a raw LoRa socket
        self.lora_sock = usocket.socket(usocket.AF_LORA, usocket.SOCK_RAW)
        self.lora_sock.setblocking(False)
        self.lora_tx_done = False
        self.watchdog.feed()
        self.lora.callback(trigger=(LoRa.RX_PACKET_EVENT | LoRa.TX_PACKET_EVENT), handler=self._lora_cb)
        self.watchdog.feed()
        if uos.uname()[0] == "LoPy":
            self.window_compensation = -1000
        else:
            self.window_compensation = -6000
        self.watchdog.feed()
        self._log('LoRaWAN nano gateway online')

    def stop(self):
        """
        Stops the LoRaWAN nano gateway.
        """

        self._log('Stopping...')

        # send the LoRa radio to sleep
        self.lora.callback(trigger=None, handler=None)
        self.lora.power_mode(LoRa.SLEEP)

        # stop the NTP sync
        self.rtc.ntp_sync(None)

        # cancel all the alarms
        self.stat_alarm.cancel()
        self.pull_alarm.cancel()

        # signal the UDP thread to stop
        self.udp_stop = True
        while self.udp_stop:
            utime.sleep_ms(50)

        # disable WLAN
        self.wlan.disconnect()
        self.wlan.deinit()

    def _connect_to_wifi(self):
        self.wlan.connect(self.ssid, auth=(None, self.password))
        while not self.wlan.isconnected():
            utime.sleep_ms(50)
            self.watchdog.feed()
        self._log('WiFi connected to: {}', self.ssid)

    def _dr_to_sf(self, dr):
        sf = dr[2:4]
        if sf[1] not in '0123456789':
            sf = sf[:1]
        return int(sf)

    def _dr_to_bw(self, dr):
        bw = dr[-5:]
        if bw == 'BW125':
            return LoRa.BW_125KHZ
        elif bw == 'BW250':
            return LoRa.BW_250KHZ
        else:
            return LoRa.BW_500KHZ

    def _sf_bw_to_dr(self, sf, bw):
        dr = 'SF' + str(sf)
        if bw == LoRa.BW_125KHZ:
            return dr + 'BW125'
        elif bw == LoRa.BW_250KHZ:
            return dr + 'BW250'
        else:
            return dr + 'BW500'

    def _lora_cb(self, lora):
        """
        LoRa radio events callback handler.
        """

        events = lora.events()
        if events & LoRa.RX_PACKET_EVENT:
            self.rxnb += 1
            self.rxok += 1
            rx_data = self.lora_sock.recv(256)
            stats = lora.stats()
            packet = self._make_node_packet(rx_data, self.rtc.now(), stats.rx_timestamp, stats.sfrx, self.bw, stats.rssi, stats.snr)
            self._push_data(packet)
            self._log('Received packet: {}', packet)
            self.rxfw += 1
        if events & LoRa.TX_PACKET_EVENT:
            self.txnb += 1
            lora.init(
                mode=LoRa.LORA,
                region=LoRa.EU868,
                frequency=self.frequency,
                bandwidth=self.bw,
                sf=self.sf,
                preamble=8,
                coding_rate=LoRa.CODING_4_5,
                tx_iq=True
                )

    def _freq_to_float(self, frequency):
        """
        MicroPython has some inprecision when doing large float division.
        To counter this, this method first does integer division until we
        reach the decimal breaking point. This doesn't completely elimate
        the issue in all cases, but it does help for a number of commonly
        used frequencies.
        """

        divider = 6
        while divider > 0 and frequency % 10 == 0:
            frequency = frequency // 10
            divider -= 1
        if divider > 0:
            frequency = frequency / (10 ** divider)
        return frequency

    def _make_stat_packet(self):
        now = self.rtc.now()
        STAT_PK["stat"]["time"] = "%d-%02d-%02d %02d:%02d:%02d GMT" % (now[0], now[1], now[2], now[3], now[4], now[5])
        STAT_PK["stat"]["rxnb"] = self.rxnb
        STAT_PK["stat"]["rxok"] = self.rxok
        STAT_PK["stat"]["rxfw"] = self.rxfw
        STAT_PK["stat"]["dwnb"] = self.dwnb
        STAT_PK["stat"]["txnb"] = self.txnb
        return ujson.dumps(STAT_PK)

    def _make_node_packet(self, rx_data, rx_time, tmst, sf, bw, rssi, snr):
        RX_PK["rxpk"][0]["time"] = "%d-%02d-%02dT%02d:%02d:%02d.%dZ" % (rx_time[0], rx_time[1], rx_time[2], rx_time[3], rx_time[4], rx_time[5], rx_time[6])
        RX_PK["rxpk"][0]["tmst"] = tmst
        RX_PK["rxpk"][0]["freq"] = self._freq_to_float(self.frequency)
        RX_PK["rxpk"][0]["datr"] = self._sf_bw_to_dr(sf, bw)
        RX_PK["rxpk"][0]["rssi"] = rssi
        RX_PK["rxpk"][0]["lsnr"] = snr
        RX_PK["rxpk"][0]["data"] = ubinascii.b2a_base64(rx_data)[:-1]
        RX_PK["rxpk"][0]["size"] = len(rx_data)
        return ujson.dumps(RX_PK)

    def _push_data(self, data):
        token = uos.urandom(2)
        packet = bytes([PROTOCOL_VERSION]) + token + bytes([PUSH_DATA]) + ubinascii.unhexlify(self.id) + data
        with self.udp_lock:
            try:
                self.sock.sendto(packet, self.server_ip)
            except Exception as ex:
                self._log('Failed to push uplink packet to server: {}', ex)

    def _pull_data(self):
        token = uos.urandom(2)
        packet = bytes([PROTOCOL_VERSION]) + token + bytes([PULL_DATA]) + ubinascii.unhexlify(self.id)
        with self.udp_lock:
            try:
                self.sock.sendto(packet, self.server_ip)
            except Exception as ex:
                self._log('Failed to pull downlink packets from server: {}', ex)

    def _ack_pull_rsp(self, token, error):
        TX_ACK_PK["txpk_ack"]["error"] = error
        resp = ujson.dumps(TX_ACK_PK)
        packet = bytes([PROTOCOL_VERSION]) + token + bytes([PULL_ACK]) + ubinascii.unhexlify(self.id) + resp
        with self.udp_lock:
            try:
                self.sock.sendto(packet, self.server_ip)
            except Exception as ex:
                self._log('PULL RSP ACK exception: {}', ex)

    def _send_down_link(self, data, tmst, datarate, frequency):
        """
        Transmits a downlink message over LoRa.
        """

        self.lora.init(
            mode=LoRa.LORA,
            region=LoRa.EU868,
            frequency=frequency,
            bandwidth=self._dr_to_bw(datarate),
            sf=self._dr_to_sf(datarate),
            preamble=8,
            coding_rate=LoRa.CODING_4_5,
            tx_iq=True
            )
        while utime.ticks_diff(utime.ticks_cpu(), tmst) > 0:
            pass
        self.lora_sock.settimeout(1)
        self.lora_sock.send(data)
        self.lora_sock.setblocking(False)
        self._log(
            'Sent downlink packet scheduled on {:.3f}, at {:,d} Hz using {}: {}',
            tmst / 1000000,
            frequency,
            datarate,
            data
        )

    def _udp_thread(self):
        """
        UDP thread, reads data from the server and handles it.
        """

        while not self.udp_stop:
            gc.collect()
            try:
                data, src = self.sock.recvfrom(1024)
                _token = data[1:3]
                _type = data[3]
                if _type == PUSH_ACK:
                    self._log("Push ack")
                elif _type == PULL_ACK:
                    self._log("Pull ack")
                elif _type == PULL_RESP:
                    self.dwnb += 1
                    ack_error = TX_ERR_NONE
                    tx_pk = ujson.loads(data[4:])
                    payload = ubinascii.a2b_base64(tx_pk["txpk"]["data"])
                    # depending on the board, pull the downlink message 1 or 6 ms upfronnt
                    tmst = utime.ticks_add(tx_pk["txpk"]["tmst"], self.window_compensation)
                    t_us = utime.ticks_diff(utime.ticks_cpu(), utime.ticks_add(tmst, -15000))
                    #if 1000 < t_us < 10000000:
                    if -10000000 < t_us < 10000000000:    
                        self.uplink_alarm = Timer.Alarm(
                            handler=lambda x: self._send_down_link(
                                payload,
                                tmst, tx_pk["txpk"]["datr"],
                                int(tx_pk["txpk"]["freq"] * 1000 + 0.0005) * 1000
                            ),
                            us=t_us
                        )
                    else:
                        ack_error = TX_ERR_TOO_LATE
                        self._log('Downlink timestamp error!, t_us: {}', t_us)
                    self._ack_pull_rsp(_token, ack_error)
                    self._log("Pull rsp")
            except usocket.timeout:
                pass
            except OSError as ex:
                if ex.args[0] != errno.EAGAIN:
                    self._log('UDP recv OSError Exception: {}', ex)
            except Exception as ex:
                self._log('UDP recv Exception: {}', ex)

            self.watchdog.feed()
            # self._log("Feeding the dog")

            # wait before trying to receive again
            utime.sleep_ms(UDP_THREAD_CYCLE_MS)

        # we are to close the socket
        self.sock.close()
        self.udp_stop = False
        self._log('UDP thread stopped')

    def _log(self, message, *args):
        """
        Outputs a log message to stdout.
        """

        print('[{:>10.3f}] {}'.format(
            utime.ticks_ms() / 1000,
            str(message).format(*args)
            ))

Instead for the final device the codes are these:

config

#configuration
from network import LoRa

#application-level device identifier
DEVICE_ID = 'eui-70b3d57ed0050435'

# authentication credentials (specific for each device, generated by LoRa backend)
# LORA_CRED_ABP = ('01e1a5f3', 'f71c36d3499d4962f8966b4d7abe271f', '7f9d74a6966264fbf6e7d13ec0e70509')
LORA_CRED_ABP = ('260B74BE', 'B6157C8F59EE1E7399ED47C5A9339587', 'C5DEE7DB15730B9606036B3F91A31B59')
# initialized (hard-coded) sampling/sending interval (will be modified and adapted by the synchronization mechanism)
INTERVAL_PRE = 120000 # (milliseconds)

# led activation (for testing only)
LED_ON = True

### It is suggested to not modify the following configurations

# authentication method
# ABP (Authentication By Personalization) suggested.
# ABP = False  enables OTA (Over The Air authentication)
ABP = True
# For OTA specific OTA-credentials must be used
#LORA_CRED_OTAA = ubinascii.unhexlify('fe22989049d5b370','0000000000000000', '4b8b613f97a82b602f98a03ef8b07c3b')


# LoRa payload format
# (2 Bytes for device ID, 8 float numbers: temp humid ph1 ph2 ph3 volt1 volt2 volt3)
LORA_PKG_FORMAT = "!Hffffffff"

# waiting time (for receive windows to expire)
WAITING_SLEEP = 8 #seconds

# LoRa PHY settings
LORA_FREQUENCY = 868100000
LORA_NODE_DR = 0 # LoRa datarate DR=0 sets SF = 12, DR=5 sets SF = 7 (DR=0 suggested for maximum range)
LORA_DEVICE_CLASS = LoRa.CLASS_C
LORA_REGION = LoRa.EU868 # LORAWAN region (Europe)
# alternatives:
# Asia = LoRa.AS923
# Australia = LoRa.AU915
# United States = LoRa.US915

loranet

#!/usr/bin/env python

import config
from network import LoRa
import socket
import binascii
import struct
import time
import _thread
import pycom
import time

class LoraNet:

    def __init__(self, sleep_time, check_rx, frequency, dr, region, activation, device_class=LoRa.CLASS_C, auth = None):
        self.sleep_time = sleep_time
        self.check_rx = check_rx
        self.frequency = frequency
        self.dr = dr
        self.region = region
        self.device_class = device_class
        self.activation = activation
        self.auth = auth
        self.sock = None
        self._exit = False
        self.s_lock = _thread.allocate_lock()
        self.lora = LoRa(mode=LoRa.LORAWAN, region = self.region, device_class = self.device_class)
        self._process_ota_msg = None

    def stop(self):
        self._exit = True

    def init(self, process_msg_callback):
        self._process_ota_msg = process_msg_callback

    def read_sleep_time(self):
        return self.sleep_time

    def read_check_rx(self):
        return self.check_rx

    def receive_callback(self, lora):
        #callback on reception ack-sync
        events = lora.events()
        if events & LoRa.RX_PACKET_EVENT:
            rx, port = self.sock.recvfrom(256)
            #decode received meassage and extract sleep time
            rx_data = rx.decode()
            rx_sleep_time = int(rx_data.split(',')[1].split('.')[0])
            print('Ack/sync received. Decoded received sleep time', rx_sleep_time)
            self.sleep_time = rx_sleep_time
            self.check_rx = True
            if config.LED_ON:
                #toggle blue led, message received
                pycom.rgbled(0x0000FF) #blue
                print('Received, blue led on')

    def connect(self):
        if self.activation != LoRa.OTAA and self.activation != LoRa.ABP:
            raise ValueError("Invalid Lora activation method")
        if len(self.auth) < 3:
            raise ValueError("Invalid authentication parameters")

        self.lora.callback(trigger=LoRa.RX_PACKET_EVENT, handler=self.receive_callback)

        if self.activation == LoRa.OTAA:
            # set the 3 default channels to the same frequency
            self.lora.add_channel(0, frequency=self.frequency, dr_min=0, dr_max=5)
            self.lora.add_channel(1, frequency=self.frequency, dr_min=0, dr_max=5)
            self.lora.add_channel(2, frequency=self.frequency, dr_min=0, dr_max=5)
        else:
            # set the 3 default channels as per LoRaWAN specification
            self.lora.add_channel(0, frequency=868100000, dr_min=0, dr_max=5)
            self.lora.add_channel(1, frequency=868300000, dr_min=0, dr_max=5)
            self.lora.add_channel(2, frequency=868500000, dr_min=0, dr_max=5)

        # remove all the non-default channels
        for i in range(3, 16):
            self.lora.remove_channel(i)

        # authenticate with abp or ota
        if self.activation == LoRa.OTAA:
            self._authenticate_otaa(self.auth)
        else:
            self._authenticate_abp(self.auth)

        # create socket to server
        self._create_socket()

    def _authenticate_otaa(self, auth_params):
        # create an OTAA authentication params
        self.dev_eui = binascii.unhexlify(auth_params[0])
        self.app_eui = binascii.unhexlify(auth_params[1])
        self.app_key = binascii.unhexlify(auth_params[2])

        self.lora.join(activation=LoRa.OTAA, auth=(self.dev_eui, self.app_eui, self.app_key), timeout=0, dr=self.dr)

        while not self.lora.has_joined():
            time.sleep(2.5)
            print('Not joined yet...')

    def has_joined(self):
        return self.lora.has_joined()

    def _authenticate_abp(self, auth_params):
        # create an ABP authentication params
        self.dev_addr = struct.unpack(">l", binascii.unhexlify(auth_params[0]))[0]
        self.nwk_swkey = binascii.unhexlify(auth_params[1])
        self.app_swkey = binascii.unhexlify(auth_params[2])

        self.lora.join(activation=LoRa.ABP, auth=(self.dev_addr, self.nwk_swkey, self.app_swkey))

    def _create_socket(self):
        # create a LoRa socket
        self.sock = socket.socket(socket.AF_LORA, socket.SOCK_RAW)
        # set the LoRaWAN data rate
        self.sock.setsockopt(socket.SOL_LORA, socket.SO_DR, self.dr)
        # make the socket non blocking
        self.sock.setblocking(False)

    def send(self, packet):
        with self.s_lock:
            #self.lora.nvram_restore()
            self.sock.send(packet)
            #self.lora.nvram_save()
            print('Sent data', packet)
            if config.LED_ON:
                # green led toggle on message sent
                pycom.rgbled(0x00FF00) #green
                print('Sent data, green led on')

main

#!/usr/bin/env python
#
# Copyright (c) 2019, Pycom Limited.
#
# This software is licensed under the GNU GPL version 3 or any
# later version, with permitted additional terms. For more information
# see the Pycom Licence v1.0 document supplied with this file, or
# available at https://www.pycom.io/opensource/licensing
#

from network import LoRa
import socket
import binascii
import struct
import time
import config

# initialize LoRa in LORAWAN mode.
# Please pick the region that matches where you are using the device:
# Asia = LoRa.AS923
# Australia = LoRa.AU915
# Europe = LoRa.EU868
# United States = LoRa.US915
lora = LoRa(mode=LoRa.LORAWAN, region=LoRa.EU868)

# create an ABP authentication params
dev_addr = struct.unpack(">l", binascii.unhexlify('260B74BE'))[0]
nwk_swkey = binascii.unhexlify('B6157C8F59EE1E7399ED47C5A9339587')
app_swkey = binascii.unhexlify('C5DEE7DB15730B9606036B3F91A31B59')

# remove all the non-default channels
for i in range(3, 16):
    lora.remove_channel(i)

# set the 3 default channels to the same frequency
lora.add_channel(0, frequency=config.LORA_FREQUENCY, dr_min=0, dr_max=5)
lora.add_channel(1, frequency=config.LORA_FREQUENCY, dr_min=0, dr_max=5)
lora.add_channel(2, frequency=config.LORA_FREQUENCY, dr_min=0, dr_max=5)

# join a network using ABP (Activation By Personalization)
lora.join(activation=LoRa.ABP, auth=(dev_addr, nwk_swkey, app_swkey))

# create a LoRa socket
s = socket.socket(socket.AF_LORA, socket.SOCK_RAW)

# set the LoRaWAN data rate
s.setsockopt(socket.SOL_LORA, socket.SO_DR, config.LORA_NODE_DR)

# make the socket non-blocking
s.setblocking(False)

for i in range (200):
    pkt = b'PKT #' + bytes([i])
    print('Sending:', pkt)
    s.send(pkt)
    time.sleep(4)
    rx, port = s.recvfrom(256)
    if rx:
        print('Received: {}, on port: {}'.format(rx, port))
    time.sleep(6)

Can you help me understand if the problem is the code on the boards or the configuration of the nanogateway and end device on the TTN server ?

Your nano gateway is not a LoRaWAN compatible gateway and won’t work with LoRaWAN. The hardware is not capable of performing required data acquisition at 8 frequencies in parallel.

You need to disconnect the ‘gateway’ from TTN as it will cause issues for other users and get a LoRaWAN compatible gateway if you want to use TTN.

2 Likes

Hi,
thanks for your reply. I am surprised that you say lopy4 is not compatible with LORAWAN, I configured the boards following this tutorial:
https://core-electronics.com.au/videos/pycom-lopy4-nano-gateway-for-lorawan.
I tried registering the two boards also on a chirpstack server and using OTAA authentication for the end device. With this authentication I see the logs of the packets received on the nano gateway, instead on the chirpsatck server I see join requests that are never accepted.
Could the problem be on the chirpstack server configuration ?

It is not a LoRaWAN Gateway, even though it handles LoRaWAN messages, it is an example of what we describe as a Single Channel Packet Forwarder (SCPF). These were occassionally used as a low cost option to explore the technology in the early days of LoRaWAN ( inc. TTN) when full gws cost>$1000-1500 before it was realised how limited and disruptive their capabilities were, low cost gws are now <$80-120…… unfortunately we cannot sensor the internet to remove bad advice :wink: use forum search to see that this is regularly discussed.

As Jac advised, not supported, please disconnect it from TTN.

Note Pycom also offer a low cost self build gw if you wish to experiment whilst staying with the brand…. Otherwise look at e.g. TTIG or various Dragino, RAK, other brands…. Be careful to ensure you pick a full 8 channel gw not a single or dual channel device……use these for Lora proprietary or p2p only :wink:

2 Likes

Hi,
thank you very much for the detailed answer. I have disconnected the gateway from the TTN server.
I would like to ask you a suggestion, I have implemented a chirpstack LoRaWAN network stack on a dedicated server, is it possible to use a lopy4 as a gateway with some special configuration with single channel transmission (SCPF) ?

Its ‘possible’, but limited functionality and ultimately not very rewarding - recommend you get a LoRaWAN Gateway then use your 2nd lopy4 as basis of another node to get value out of it! :slight_smile: For the ‘how’ we would refer you to Chirpstack’s forum - as this forum is dedicated to TTN :wink:

2 Likes

Thank you so much for your support, could you suggest me any GW for Europe frequency not really expensive and good to start with?

As above!

1 Like