Greetings, I am using chirpstack LoRaWAN stack with the RAK2245 concentrator on a RPi 3B+ and LoPy4 as the end-devices. LoPy is set to function as a class C node. I am facing the current issue:
The LoPy is unable to receive valid LoRaWAN frames when the socket is set to listen on LoRaWAN mode. Raw LoRa reception works fine. The LoPy can send successfuly and the LoRaWAN frames are displayed correctly on the application server. However, the downlink packets are never received at the LoPy. I checked the concentrator and they are transmitted without issues. Downlink frames follow the protocol specifications for tx frequency and coding rate. Using the same values for frequency and coding rate and transmitting raw LoRa to the end device works without problems. The code at the LoPy for LoRaWAN reception is taken from Pycom’s website.
Concentrator: RAK2245 on Raspberry Pi 3 model B+
End Device: Pycom LoPy4 on Pycom Expansion Board v3.1
OS: Raspbian 10 Buster
Chirpstack gateway bridge, network server and application server all are running on the same RPi using localhost.
[Network Server config file]:
# PostgreSQL settings.
#
# Please note that PostgreSQL 9.5+ is required.
[postgresql]
#
#
# The following connection parameters are supported:
#
# * dbname - The name of the database to connect to
# * user - The user to sign in as
# * password - The user's password
# * host - The host to connect to. Values that start with / are for unix domain sockets. (default is localhost)
# * port - The port to bind to. (default is 5432)
# * sslmode - Whether or not to use SSL (default is require, this is not the default for libpq)
# * fallback_application_name - An application_name to fall back to if one isn't provided.
# * connect_timeout - Maximum wait for connection, in seconds. Zero or not specified means wait indefinitely.
# * sslcert - Cert file location. The file must contain PEM encoded data.
# * sslkey - Key file location. The file must contain PEM encoded data.
# * sslrootcert - The location of the root certificate file. The file must contain PEM encoded data.
#
# Valid values for sslmode are:
#
# * disable - No SSL
# * require - Always SSL (skip verification)
# * verify-ca - Always SSL (verify that the certificate presented by the server was signed by a trusted CA)
# * verify-full - Always SSL (verify that the certification presented by the server was signed by a trusted CA and the server host name matches the one in the certificate)
dsn="postgres://chirpstack_ns:dbpassword@localhost/chirpstack_ns?sslmode=disable"
# Redis settings
#
# Please note that Redis 2.6.0+ is required.
[redis]
#
url="redis://localhost:6379"
# Network-server settings.
[network_server]
# Network identifier (NetID, 3 bytes) encoded as HEX (e.g. 010203)
net_id="000000"
# LoRaWAN regional band configuration.
[network_server.band]
name="EU_863_870"
# LoRaWAN network related settings.
[network_server.network_settings]
# Extra channel configuration.
#
# Use this for LoRaWAN regions where it is possible to extend the by default
# available channels with additional channels (e.g. the EU band).
# The first 5 channels will be configured as part of the OTAA join-response
# (using the CFList field).
# The other channels (or channel / data-rate changes) will be (re)configured
# using the NewChannelReq mac-command.
#
[[network_server.network_settings.extra_channels]]
frequency=867100000
min_dr=0
max_dr=5
[[network_server.network_settings.extra_channels]]
frequency=867300000
min_dr=0
max_dr=5
[[network_server.network_settings.extra_channels]]
frequency=867500000
min_dr=0
max_dr=5
[[network_server.network_settings.extra_channels]]
frequency=867700000
min_dr=0
max_dr=5
[[network_server.network_settings.extra_channels]]
frequency=867900000
min_dr=0
max_dr=5
# Class B settings
[network_server.network_settings.class_b]
# Ping-slot data-rate.
ping_slot_dr=0
# Ping-slot frequency (Hz)
#
# Set this to 0 to use the default frequency plan for the configured region
# (which could be frequency hopping).
ping_slot_frequency=0
# Network-server API
#
# This is the network-server API that is used by ChirpStack Application Server or other
# custom components interacting with ChirpStack Network Server.
[network_server.api]
# ip:port to bind the api server
bind="0.0.0.0:8000"
# Backend defines the gateway backend settings.
#
# The gateway backend handles the communication with the gateway(s) part of
# the LoRaWAN network.
[network_server.gateway.backend]
# Backend
type="mqtt"
# MQTT gateway backend settings.
#
# This is the backend communicating with the LoRa gateways over a MQTT broker.
[network_server.gateway.backend.mqtt]
# MQTT topic templates for the different MQTT topics.
#
# The meaning of these topics are documented at:
#
# The default values match the default expected configuration of the
# ChirpStack Gateway Bridge MQTT backend. Therefore only change these values when
# absolutely needed.
# Event topic template.
event_topic="gateway/+/event/+"
# Command topic template.
#
# Use:
# * "{{ .GatewayID }}" as an substitution for the LoRa gateway ID
# * "{{ .CommandType }}" as an substitution for the command type
command_topic_template="gateway/{{ .GatewayID }}/command/{{ .CommandType }}"
server="tcp://localhost:1883"
# Connect with the given username (optional)
username=""
# Connect with the given password (optional)
password=""
# Metrics collection settings.
[metrics]
# Timezone
#
# The timezone is used for correctly aggregating the metrics (e.g. per hour,
# day or month).
# Example: "Europe/Amsterdam" or "Local" for the the system's local time zone.
timezone="Local"
# Join-server settings.
[join_server]
# Default join-server settings.
#
# This join-server will be used when resolving the JoinEUI is set to false
# or as a fallback when resolving the JoinEUI fails.
[join_server.default]
# hostname:port of the default join-server
#
# This API is provided by ChirpStack Application Server.
server="http://localhost:8003"