ESP8266 Community Forum

- Thu Mar 03, 2016 9:00 am #42310 Dear All,

my issue is the following:

I have used 14 of esp e-12 in the past, without any major issues. Now I was running out of devices, so purchased 10 of e-12 from ebay.
In some devices - I can not initial the flashing mode - gpio0- low, gpio2- high, gpio15 low, en high - the process does not start, reboot does not help.
if im lucky, I can flash the device, any time, many times, but after a successful flashing, i can not connect to esp using any softwares, like Esplorer.
Im using the same pin setting as before on my other, working esps, but I can not connect....

any idea to fix it? is there anybody, had the same issue?

thank you in advance!
R

- Thu Mar 03, 2016 1:46 pm #42346 GPIO^15 = GND
GPIO^2 = 3.3(PULLED UP)
GPIO^0 =3.3(PULLED UP)
CH_PD =3.3(PULLED UP)

MAKE SURE THAT WHEN YOU DONE YOUR FLASHING PROCESS GPIO^0 MUST BE PULL-UP(3.3V)

READ THIS LINK , http://www.esp8266.com/viewtopic.php?f=23&t=6571&start=8

IF AFTER APPLY ALL PROCESS AND STILL STUCK ONNNNNNNN >> CONTACT ME
kamalsonani11@gmail.com
THATS ALL

- Thu Mar 03, 2016 3:22 pm #42353 After successfully flashed 3 additional e-12 with nodemcu_float_0.9.6-dev_20150704.bin, I still can not connect to any devices using ESPlorer..
I can soft reset all of them, but after connection I have a screen like this:

PORT OPEN 9600

Communication with MCU...
Got answer! AutoDetect firmware...

Can't autodetect firmware, because proper answer not received.

in the last line i have some squares, unreadable, and gives me squares if I send a command like "heap"

any suggestion to fix it?
thank a lot in advance!
G

- Mon Mar 07, 2016 9:38 am #42615 It is strange, i could bring back one esp-12 to live, but only one for the time being:

100 ohm resistor serial to rx /on board, and a 10k resistor to pull down gpio15

after this mod, i could connect to esp-12 via esplorer, without any issues.
The problem is, --- its working just in one case, no more.... but maybe helps to someone else...