Bricked two SqueezeAMPs - how to recover?

[benh]

Yep, that was it. I booted to recovery mode, went into the NVS editor, fixed the argument, and it's working now. Thanks for all of the help...definitely would have been a lot less of a slog if I'd gotten a different serial adapter much earlier!

For reference, the problem was here:
...

[benh]

I was correct that something is amiss with my trusty serial adapter. I got one of the FTDI adapters and I have a non-garbage console now, which makes all of this much easier to diagnose.

As far as I can tell, the problematic unit is in a reboot loop, I *suspect* that the reason is that...

[benh]

That I have not done. Is there a way to do that from the web UI? If not, I'll have to solve the console issue first.

[benh]

I have connected via serial console, which caused the SA to boot into recovery mode and be available via wifi. I used the web UI to upload a squeezelite binary package, such as squeezelite-esp32-master-v4.3-SqueezeAmp-16-21254. That's successful, but it never comes back from that reboot.
...

[benh]

Yes, twice quickly.

[benh]

It powers up without anything attached to the serial connections. The status led illuminates green and it will blink green twice quickly about every 3 seconds. The red led behind the barrel jack also lights up.

[benh]

It is interesting. I can't help but think that I have a serial adapter issue of some kind. I think I'll try a different USB-Serial dongle and make up a different adapter.

[benh]

(Made some edits to be below after double checking things.)

Connecting only TX, RX and GND does not cause the system to come up.

Connecting only TX, RX, GND, and RST DOES cause the system to come up.

Connecting only TX, RX, GND, and DWL DOES cause the system to...

[benh]

In fact, just screwing around, I have this one SA that is misbehaving that I can consistently make come online in recovery mode by plugging into serial console. Once online, I can hit the web UI and upload a local copy of a recent firmware. It will go through the upload/upgrade process, proclaim success,...

[benh]

It's difficult to believe that it's a coincidence. I can have an SA sitting here borked and offline, plug in serial console and suddenly there it is, network visible.

[benh]

(I have tested every single baud rate from 300 to 230400, and they all are garbled.)

[benh]

So, success.

I bodged together an adapter to connect my USB to serial adapter to the 6 pin header and I managed to recover both of the SqueezeAmps, but I do not understand how or why it worked.

As I would connect the serial adapter to a SqueezeAmp, with TX, RX, GND, DWL and...

[benh]

Yeah, I tried all of that but the title was not editable. Either advanced user malfunction or there’s a timeout in the ability to edit a title....

[benh]

Thanks. I'll cobble something up and report back. Don't think I can change the thread title, or at least can't find where that is done.

[benh]

I do have a USB to serial adapter. One that's USB-C to rolled/router console. Another that's USB-A to DB9. If neither of those is the right type, happy to go get the right one.

I assume I need some kind of adapter to connect between the 6 pin header and the serial adapter?

[benh]

I bought a couple of SqueezeAMPs some time ago and finally had a use for them. Hooked one up, went through the setup process, and all was well. Got it connected to my media network and went to upgrade the firmware, and had some issues. I ended up downloading a recent firmware (squeezelite-esp32-master-v4.3-SqueezeAmp-16-21234.bin)...