[Feature Request]: Dual bluetooth and wifi mode

[vranki]

Platform

ESP32

Description

It would be useful to be able to connect to a node via wifi at home, and otherwise use bluetooth. My request is an "dual mode" which does the following:

1. Check if wifi is available - if it is, connect to it.
2. If no wifi or wifi is disconnected, turn on bluetooth. If someone connects via bluetooth, keep it on.
3. If Bluetooth is disconnected or nobody connects to it for N seconds, goto 1

This should be doable with existing hardware limitations.

[dl9sau]

In my lora-aprs firmware I had a similar approach.

Devices like the simple lilygo lora32 have a harddware design limitation that makes both, bluetooth and wifi, unstable when startet concurrently.

Other devices like the t-beam have no problems of using both at the same time (separate threads).
But even then, wifi consumes more power on a portable tracker. That's why I have a general config option:
start bt
or
start wifi
or
wait for bt client, after wait timeout (i.e. 30s), shutdown bt and start wifi.

Even more, I have a button/lcd-menu option to start wifi (and on a lora32 device it stops bluetooth again).

So I always have access to the web frontend for configuration when needed.

I comment this here because I have currently a usecase (a bit vice versa):
My heltec wireless tracker is configured as mqtt gateway with wifi connection to the internet. I forgot to install the optional webserver.
I administered it via remote admin commands via lora. I added the public key of my t1000e.
My t1000e has changed his key without asking (well known entropy bug that lead to multible persons had the same key.. firmware detected that and regenerated). So far so good - but now the device cannot remote administer the heltec wireless tracker.
And the heltec wireless tracker still uses wifi, has no webserver, and I cannot turn bluetooth on for directly connecting the smartphone app for reconfiguration.
A button 'start bluetooth', or a boot-and-wait-for-bt-client option, as proposed, would have been convenient and would save me much time for regaining access to that device.

[TwentySixer]

I'd also like a button to easily switch between Bluetooth and Wi-Fi.
This way, you can easily connect the node to your Wi-Fi when you're at home, and then simply switch to Bluetooth and the mobile app when you're out.