MQTT/JSON and Network

So I am seeing something that I don’t understand. This was not present in V2.2.11 firmware release.

I have two nodes (so far) that I am parsing the MQTT/JSON data. With the firmware update to V2.2.16 I am seeing some data coming across for channel 239 (I only have one channel (Channel 0) active).

It appears to be showing RSSI and SNR in the packet. The “Type” data field is empty as well.

Here is what is coming across the JSON/MQTT network:
Client (null) sending SUBSCRIBE (Mid: 1, Topic: msh/2/json/#, QoS: 0, Options: 0x00)

which JSON then outputs as:
Client (null) received PUBLISH (d0, q0, r0, m0, ‘msh/2/json/LongFast/!55c6dc90’, … (139 bytes))
{“channel”:239,“from”:2931144524,“id”:1663124531,“rssi”:-58,“sender”:“!55c6dc90”,“snr”:10,“timestamp”:1703869806,“to”:4294967295,“type”:“”}

What is that channel data that I am seeing coming across from the network? Note as stated previously the “type” value is always empty.

It is not possible to have channel 239, 8 max

Yes I agree. Hence my confusion. Could the JSON or MQTT firmware have a bug in it? Like I said it was working fine in 2.11 (just recently updated the firmware)

Something changed in firmware-2.2.13.f570204 and subsequent releases in terms of the value “type” being populated. JSON/MQTT works just as expected in firmware-2.2.11 but is broken in later releases…

Some new packet types were added.

If the type isn’t populated, the specific message does not have JSON output (yet).

You can see the changes related to MQTT/JSON between 2.2.11 and 2.2.13 here: Comparing v2.2.11.10265aa...v2.2.13.f570204 · meshtastic/firmware · GitHub (look in the file src/mqtt/MQTT.cpp).

As you can see, the channel number is updated based on its name. Furthermore, some new telemetry type (power metrics) as well as RSSI and SNR have been added.