Activation Lopy with TTN network using OTAA method

[oorrab]

@jmarcelino - similar issue, but in AUS

Failing to connect LoPy1 node to TTN in Australia (Adelaide) with OTAA. New to LoRa and LoPy so have plenty of unknowns :)

Haven't managed to find a definite LoPy/TTN setup description for AU915 that works, but am attempting to set frequencies/channel-plan as per;
https://www.thethingsnetwork.org/forum/t/ttn-australian-communities/4068

os.uname()
(sysname='LoPy', nodename='LoPy', release='1.17.3.b1', version='v1.8.6-849-83e2f7f on 2018-03-19', machine='LoPy with ESP32', lorawan='1.0.2')

If I delete all channels and re-add, lora.join with timeout=0 does not return (appears to hang). Deleting extra channels and updating those needed appears to be OK.

Is there a way of confirming all channel settings?

Trying to spec a dr_max > 6 (for AU) gives a value error - is this expected, and does it matter for a basic join?

main.py as follows;

from network import LoRa
import socket
import time
import binascii
import pycom

lora = LoRa(mode=LoRa.LORAWAN, region=LoRa.AU915, adr=False, tx_retries=0, device_class=LoRa.CLASS_A)

for i in range(16, 65):
    print("Removing channel:", i)
    lora.remove_channel(i)
for i in range(66, 72):
    print("Removing channel:", i)
    lora.remove_channel(i)

print("Adding channels...")
for i in range(8, 16):
    print("Adding channel:", i)
    f = 915200000 + i * 200000
    print("Frequency:", f)
    lora.add_channel(i, frequency=f, dr_min=0, dr_max=3)

print("Adding channel 65")
f = 917500000
print("Frequency:", f)
lora.add_channel(65, frequency=f, dr_min=4, dr_max=4)

for i in range(0, 8):
    print("Adding channel ", i)
    f = 923300000 + i * 600000
    print("Frequency:", f)
    lora.add_channel(i, frequency=f, dr_min=0, dr_max=6)

app_eui = binascii.unhexlify('70B3DAAAAAA0BBA1')
app_key = binascii.unhexlify('BC1186924E6EAAAAAAAAE995921392C7')

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

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

Also tried the above with the channel removes only (no adds to try the defaults) with no avail.

Any advice on troubleshooting this further? Have tested on several gateways and driven pretty close so shouldn't have a range issue. Node running with PyCom antenna.

As an aside - it would be awesome to add a LoRa.AU915.TTN to handle this - looks like the Aus TTN community is fairly well coordinated on this sub-band2 setup. Perhaps a non-issue if there is a solid LoPy-Aus-TTN setup guide somewhere. I'll create one if I can get to the bottom of it!

[asavvin]

Hi,

search over the forum. Still unclear if this is possible to use OTAA activation for US915 Lopy with TTN gateway. Does anybody have success?

[jimpower]

@oorrab said in Activation Lopy with TTN network using OTAA method:

for i in range(16, 65):
print("Removing channel:", i)
lora.remove_channel(i)
for i in range(66, 72):
print("Removing channel:", i)
lora.remove_channel(i)

print("Adding channels...")
for i in range(8, 16):
print("Adding channel:", i)
f = 915200000 + i * 200000
print("Frequency:", f)
lora.add_channel(i, frequency=f, dr_min=0, dr_max=3)

print("Adding channel 65")
f = 917500000
print("Frequency:", f)
lora.add_channel(65, frequency=f, dr_min=4, dr_max=4)

for i in range(0, 8):
print("Adding channel ", i)
f = 923300000 + i * 600000
print("Frequency:", f)
lora.add_channel(i, frequency=f, dr_min=0, dr_max=6)

I could be wrong but looking at your code adding the channels back in your sub band 2 should be ch 8-15 and they start at 916.8 - 918.2, yours looks like you are starting from 915.2 try adjusting these and let us know your results.

[asavvin]

I am in US915

[oorrab]

Thanks for the reply @jimpower

I put in the print statements (output below) to check the maths/python, but can easily be missing something radio-esque! Indeed, these are spec'd for gateways at;
https://www.thethingsnetwork.org/forum/t/ttn-australian-communities/4068/9

The node config should replicate right? Nothing to switch as a node vs gateway?

AU ISM 915
Ch# | direc | f/MHz | BW/kHz | data rate
8 | up | 916.8 | 125 | DR0 - DR3
9 | up | 917.0 | 125 | DR0 - DR3
10 | up | 917.2 | 125 | DR0 - DR3
11 | up | 917.4 | 125 | DR0 - DR3
12 | up | 917.6 | 125 | DR0 - DR3
13 | up | 917.8 | 125 | DR0 - DR3
14 | up | 918.0 | 125 | DR0 - DR3
15 | up | 918.2 | 125 | DR0 - DR3
65 | up | 917.5 | 500 | DR4
0 | down | 923.3 | 500 | DR8 - DR13
1 | down | 923.9 | 500 | DR8 - DR13
2 | down | 924.5 | 500 | DR8 - DR13
3 | down | 925.1 | 500 | DR8 - DR13
4 | down | 925.7 | 500 | DR8 - DR13
5 | down | 926.3 | 500 | DR8 - DR13
6 | down | 926.9 | 500 | DR8 - DR13
7 | down | 927.5 | 500 | DR8 - DR13

Adding channels...
Adding channel: 8
Frequency: 916800000
Adding channel: 9
Frequency: 917000000
Adding channel: 10
Frequency: 917200000
Adding channel: 11
Frequency: 917400000
Adding channel: 12
Frequency: 917600000
Adding channel: 13
Frequency: 917800000
Adding channel: 14
Frequency: 918000000
Adding channel: 15
Frequency: 918200000
Adding channel 65
Frequency: 917500000
Adding channel 0
Frequency: 923300000
Adding channel 1
Frequency: 923900000
Adding channel 2
Frequency: 924500000
Adding channel 3
Frequency: 925100000
Adding channel 4
Frequency: 925700000
Adding channel 5
Frequency: 926300000
Adding channel 6
Frequency: 926900000
Adding channel 7
Frequency: 927500000

[jimpower]

@oorrab I don't use TTN, I deploy my own gateways which operate of frequencies outside of TTN for obvious reasons.

My node setup "up" channels replicate my Gateway 'RX" channels, if the mote or node is broadcasting on any channels outside of what the gateway is set to listen on then it will fall on deaf ears so to speak.

[asavvin]

@asavvin said in Activation Lopy with TTN network using OTAA method:

Hello!

Still unclear for me how I can connect Lopy to TTN network using OTAA method.
I was able to get connection only using ABP method w/o problem but OTAA have never worked for me.

Please advice.
Thank you

Finally I was able to get connection Lopy using OTAA with TTN gateway in US915.

[oorrab]

Hi @asavvin - could you share your code and firmware version?

Might have some differences here in AUS but would be good to know a working baseline and rule out some unknowns.

[asavvin]

@oorrab
Hi

I used Pycom Lopy with latest firmware. TTN gateway with original firmware.

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

lora = LoRa(mode=LoRa.LORAWAN, region=LoRa.US915)

dev_eui = binascii.unhexlify('xxxx')
app_eui = binascii.unhexlify('xxxx')
app_key = binascii.unhexlify('xxxx')

for channel in range(0, 72):
lora.add_channel(channel, frequency=903900000, dr_min=0, dr_max=3)

join a network using OTAA

lora.join(activation=LoRa.OTAA, auth=(dev_eui, app_eui, app_key), timeout=0, dr=4)

wait until the module has joined the network

join_wait = 0
while True:
time.sleep(2.5)
if not lora.has_joined():
print('Not joined yet...')
join_wait += 1
if join_wait == 5:
lora.join(activation=LoRa.OTAA, auth=(dev_eui, app_eui, app_key), timeout=0, dr=0)
join_wait = 0
else:
break

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, 0)

make the socket 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)

[oorrab]

@asavvin interesting you set all the channels to the same frequency. Something for me to try to help narrow this down. Frequencies different in AUS but his may take LoPy complexity out of the equation to make progress....

[asavvin]

@oorrab
in application log I can see channels actually keep changing starting from 9039...