General • Re: Progress - basically works but eventually loses MQTT connection

Using MQTT, the Picos eventually lose the connection to the broker, and that's more likely the higher the frame rate is. At 5fps, it remains stable, at 20fps it usually fails within 10 seconds.

But maybe it's not the MQTT code that causes the disconnection but the lower level lwIP code. This will be difficult to figure out.

That's my gut feeling, that it's something within LwIP, but I can't prove it. It could be the CYW43 passing the driver something incorrect, the Driver passing LwIP something incorrect, something incorrect passed to MQTT which leads to a disconnection, or maybe something harder to fathom at work. There could be multiple issues at play, specific edge cases causing a problem.

As you say; difficult to figure out.

I wonder if mosquitto is the problem.

I would doubt that as it would likely have been widely noted and documented if that were the case. And it worked absolutely fine for me with large payloads though only sent a pedestrian speeds.

It seems to me that the issue is with the Pico W side of things.

What we really need are five test cases -

• Pi to itself using internal networking
• Pi to Pi over a wired Ethernet network
• Pi to Pi over a Wi-Fi connection
• Pi to Pico or Pico W using a wired Ethernet network
• Pi to Pico W over a Wi-Fi connection

A table of what does and doesn't work may help identify commonalities in not working, even if not identifying the specific cause.

Statistics: Posted by hippy — Tue Jul 30, 2024 11:42 am

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