Hi folks,
I am working with FSK modulation and it looks like my device is successfully using FSK modulation on the 868.8MHz channel on EU868. Uplinks on all LoRa datarates arrive nicely on the gateway, sent through MQTT, to the gateway console and in the device console. However, as soon as an FSK uplink is sent by my device, while it is being picked up by the gateway and forwarded through MQTT, it does not arrive on the gateway console nor on the device console.
An excerpt of system/gateway log:
Sat Aug 17 11:57:27 2024 user.info chirpstack-mqtt-forwarder[8792]: Received gateway stats
Sat Aug 17 11:57:27 2024 user.info chirpstack-mqtt-forwarder[8792]: Sending gateway stats event, topic: eu868/gateway/ce77157009a7eba4/event/stats
Sat Aug 17 11:57:31 2024 user.info chirpstack-concentratord-sx1301[9056]: Frame received, uplink_id: 2610325176, count_us: 1806749370, freq: 868300000, bw: 250000, mod: LoRa, dr: SF7
Sat Aug 17 11:57:31 2024 user.info chirpstack-mqtt-forwarder[8792]: Received uplink frame, uplink_id: 2610325176
Sat Aug 17 11:57:31 2024 user.info chirpstack-mqtt-forwarder[8792]: Sending uplink event, uplink_id: 2610325176, topic: eu868/gateway/ce77157009a7eba4/event/up
Sat Aug 17 11:57:37 2024 user.info chirpstack-concentratord-sx1301[9056]: Frame received, uplink_id: 206270531, count_us: 1812774306, freq: 868800000, bw: 125000, mod: FSK, dr: FSK(50000)
Sat Aug 17 11:57:37 2024 user.info chirpstack-mqtt-forwarder[8792]: Received uplink frame, uplink_id: 206270531
Sat Aug 17 11:57:37 2024 user.info chirpstack-mqtt-forwarder[8792]: Sending uplink event, uplink_id: 206270531, topic: eu868/gateway/ce77157009a7eba4/event/up
Sat Aug 17 11:57:55 2024 daemon.err postmaster[2022]: 2024-08-17 09:57:55.616 UTC [2] LOG: checkpoint starting: time
Screenshot of gateway console:
I know that these two uplinks are only 6 seconds apart, I have it on a push-button, I’ve just retried with half an hour in between uplinks but that doesn’t make a difference.
Is there any form of debugging I can do to find out why these uplinks are dropped? Or any ideas for a solution?
Hardware: Raspberry Pi 3B v1.2 with Pi Supply hat running fresh Chirpstack OS install from this morning (ChirpStack Gateway OS 4.4.0 Full / LuCI openwrt-23.05 branch git-24.135.44542-f1ec9c2).
Note: I am testing the FSK modulation so cannot guarantee it is implemented 100% correctly, but given that the gateway picks it up and forwards it, it appears to me this is not the issue.