Cannot join using OTAA.

[hakan kayan]

Hi,

I am trying to establish a LoRa communication. I am a beginner.

First of all, the GitHub code is different than the webpage tutorial. I am not sure which one to follow. I tried both.

The problem was mentioned in another topic around 4 years ago. But sadly, it seems like the issue still persists.

I have 1 LoPy and 1 LoPy4. I am using LoPy as end node, and LoPy4 as a gateway. I registered both to TTN. The gateway receives uplink messages but my device can never join.

How can I debug this further?

[hakan kayan]

Hi @robert-hh,

I tried, sadly still no success. Here is what I see in my TTN gateway activity. It does not allow me to put a picture so I am adding as a code:

Receive uplink message        JoinEUI: something       DevEUI: something        Data rate: SF7BW125

The output of node LoPy as follows:

Not yet joined...

Here is my code on node:

""" OTAA Node example compatible with the LoPy Nano Gateway """

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 OTA authentication params
dev_eui = binascii.unhexlify('something')
app_eui = binascii.unhexlify('something')
app_key = binascii.unhexlify('something')

# set the 3 default channels to the same frequency (must be before sending the OTAA join request)
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 OTAA
lora.join(activation=LoRa.OTAA, auth=(dev_eui, app_eui, app_key), timeout=0, dr=config.LORA_NODE_DR)

# wait until the module has joined the network
while not lora.has_joined():
    time.sleep(2.5)
    print('Not joined yet...')

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

# 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)

time.sleep(5.0)

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)

[robert-hh]

@hakan-kayan You could switch the devices. The Lopy works better as gateway. Since it has no SPIRAM, timing is more reliable.