ESP8266 Community Forum

I have ESP rev 12E and the basic Interpreter flashed just fine.
All worked perfectly fine until I entered my own network settings in to the device...
After re-boot the serial monitor only shows garbage characters on reset (at any speed setting) and the 12E will not connect to my router. (I checked the routing table so I know that it is not connecting)

So... I figured that re-flash will re-set everything but even though re-flash forks fine... the default AP is not available.
The 12E is not bricked as I can flash code in to it just fine, it is just that it looks like the network settings do not clear even after re-flashing the interpreter.

If you have a phone or android based device download FING from google play.

With your phone connected to the router you are connected to via wifi open the app and do a scan.

See if anything ESP comes up... Give it a minute or so after you plug it in to show up if it does not.

Note if gpio's 0, 15, or 16 are being held low at boot for any reason your wifi will not connect you will not be able to access your device.

When this happens you can also sometimes reflash the device. Sometimes I flash from basic to LUA and then do a format in LUA then flash back to basic to get my settings.

Other times my settings don't hold so what I will do is save my settings several times until it reboots and then reflash basic on my esp and viola your settings are there ...

Anyhow yes the interface can be quirky at times but it does work once you get the hang of things its awesome.

Keep at it show it who is boss so to speak I can verify it works fine for the 12E so unless you have a faulty esp which I somehow doubt while still a small possible ...

Do it and do it some more you will figure out.

Take Care and good luck don't give up easy this is the best advice I can give most often it works without issue but initial settings can be somewhat uncooperative do not let this stump you though !

Things to note here. Serial terminal should be at 9600.

Must not have gpio 0 grounded.


Setting are persistent between flashes of new firmware. This is both good and bad in some respects.


Connect to the device quickly after booting up. If you put it in to a infinite loop you have 30 seconds to get in and save a blank program.

Maybe it would be good to add a button to the settings page to clear the persistent settings.