ESP8266 Community Forum

- Sat Oct 10, 2015 2:03 am #31002 My device is a ESP-12E board purchased from Alibaba.

Item: I was using this board without issue for a couple of weeks. It has been programmed, reprogrammed multiple times, both via Serial and via OTA.

Item: I have another ESP-12E board from the same order, which is still working fine.

I was programming it via Serial a few days ago, and there seemed to be an error during upload.
Okay, no issue, reset and try again. But now, the upload process starts - but is stuck at 0%. It never moves.

I pulled GPIO 0 HIGH, and reset the device, but it doesn't resume any of its old programming. On each reset, it repeats this string of gibberish (115200 baud):

rl��r��#�n����p�<����8��ǒ��p�nn��;�nĒ���b�$ rr

which is perfectly normal for programming mode. But it's entering programming mode even while GPIO0 is HIGH!
So I measured the pin voltage and it seems that it is permanently stuck at 1.5V, even with the pullup resistor. I even connected it directly to the 3v3 supply and the pin remained at 1.5V. I'm guessing the chip is likely dead, but I would like verification of that fact, and perhaps any guesses as to why / how it happened.

- Sat Oct 10, 2015 2:10 am #31003 I sh*t you not:
Literally 20 seconds after I posted this topic, I pressed the ESP-12 into the breadboard really hard out of frustration.
It is now working again.
WTF. I had unplugged and replugged the device into the breadboard multiple times before. The other ESP-12 works fine, so it's definitely not simply a matter of "check your wiring".

Welp. Hope it doesn't fail again

EDIT:
NOPE, it's gone again.

- Fri Nov 06, 2015 10:24 am #33265 1) GPIO15 -> GNG, GPIO 0 & 2 to HIGH. Check your connection's first.
2) Try other baud rates.

I feel there is nothing wrong with your board.

-Venkatesh

-Venkatesh