ESP8266 Community Forum

- Tue Jun 02, 2015 12:06 pm #19228 Hello everyone
Some days ago I received my ESP-03. After some work I got it to work.
I have been able to update the firmware to the last version of the 'AT' one.
Today I changed the firmware to NodeMCU's latest version. It worked without problems until I connected to a GPIO pin a led through a resistor.

After that, I started to get Fatal Exception (0) errors. I managed to recover the ESP by rewriting its standard firmware.
Unfortunately I needed the NodeMCU FW, so I have written it back in the ESP.

This time, I can't get it to recover back.

It keeps writing to the console garbage data that can't be analysed at any baud rate (even 74880):

Code: Select allåýÅOÂÿ0òðy,&*pòýx00ðð000<àÙ�3ÿÂÿ000þ‚þ~g�ß…ñ|®‚Âððð0‚‚ùdy�ÿ0xð󆂂‚þj
Æatal excåpúzËB‚JÒn
epc1=0x402ð188<, �É}0x00000000< epc3=0x00000p00, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x40201884, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
Fatal exception (0):
epc1=0x4020188b, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000


How can I fix the module?
Thank you!

- Wed Jun 03, 2015 8:27 am #19334 Moin,

I would check if flashing really words reliably for you.
To do that I would use esptool.py to burn the original AT firmware and then read the data back from flash and
compare them.
If there is some flashing problem due to flashing itself or communication you should see it.

My € 0,02

Cal

Get your modules here:

https://www.banggood.com/custlink/KvGGhGF4wG

- Wed Jul 15, 2015 1:13 am #23301 To anyone having the same issue, make sure that your device is powered by a 3.3V power source capable of sourcing at least 200 mA of current. Also, remember to add a 10uF or so capacitor on the rails, and position the ESP8266 as close to the capacitor as possible. I was having the above issue too until I added the capacitor; now everything is rock solid.

If that still doesn't work, then reflashing might be a good idea.

- Mon Sep 28, 2015 7:56 am #30045 Hi there, i'm facing issue just like you. until now the wifi doesn't work. It worked about a weeks ago, but now just stop working suddenly. I try reflashed but there is no hope. Seems flash successful but after reboot, at booting i got those message (fatal exception). Now i look new ESP-1 but i face same issue. what's wrong with this wifi??