Always On AP Mode/Manager Mode

[pkkrusty]

Separating out the discussion from #13362 so it's a little more visible for people searching for a hacky solution:

With an edited tasmota/tasmota_xdrv_driver/xdrv_01_9_webserver.ino (attached for 13.0.0.1)
xdrv_01_9_webserver.ino.zip, Tasmota can function in AP mode full-time, to allow management of a device with no access to wifi. This is useful for certain remote devices, like sensors, vehicle trackers, irrigation switches, AC IR controllers inside metal shipping containers or battery chargers in the middle of nowhere (my use-case is rural Africa where wifi is mostly non-existent except for people's phone hotspots).

There are certain considerations, of course. Time-keeping is usually important (but not always). $2 DS3231 modules work well for that, and are very accurate over long periods. Cheap $4 GPS modules also work well, but are kind of overkill.

Need to have

#define USE_ALWAYS_AP
#define WIFI_CONFIG_TOOL       WIFI_MANAGER
#define WIFI_SCAN_AT_RESTART   false
#define WIFI_SCAN_REGULARLY    false

Should have

#define WIFI_AP_PASSPHRASE     ""

in user_config_override.h

Tested on both ESP8266 and ESP32. With #define USE_ALWAYS_AP commented out, the webserver driver functions normally.

A nice feature is that you can enter a wifi network in the wifi section, and the unit will search for it on startup for 20 seconds, then activate AP mode if not found. Thus, you can restart the unit from the AP mode, then activate your phone's hotspot, and the unit will join it, giving it network access to update the RTC, send MQTT messages, and any other connected features. (I, for example, activate MQTT in AP mode, which triggers a restart, then the unit joins the phone hotspot, allowing remote control for troubleshooting).

Simply turning off the phone hotspot will cause the unit to search for 20 more seconds then re-activate AP mode. Thus both modes can be entered without physical access to the unit.

Here's a generic build with a number of sensor drivers and rules. I usually build with scripting/SD card, since data logging without wifi requires that.
tasmota.bin.gz

[kub3let]

I rebased against 13.4.0 and built images for more targets (ESP8266/ESP32/ESP32c3/ESP32s2)

• Flash correct image onto esp
  • factory binary via usb/uart using https://tasmota.github.io/install
  • normal binary as ota upgrade via web gui on existing tasmota devices
• Connect to Tasmota AP
• Visit http://tasmota.local

Firmware download:
tasmota-ap-13.4.0.zip

[martin072]

Nice! wouldn't it be an option for a feature request? or has that already been done?

[pkkrusty]

Has been discussed multiple times in the past. Main devs aren't interested in making it a feature. Introduces a fair amount of limitations that need to be worked around (need a RTC module to keep good time). But this hack serves my purposes quite well. I use it for remote watering stations run off solar.