ESP8266 Fatal exception

Ok, so you have this…

Fatal exception (28):

epc1=0x40245f15, epc2=0x00000000, epc3=0x401012b6, excvaddr=0x00000004, depc=0x00000000

 ets Jan  8 2013,rst cause:1, boot mode:(1,3)

 ets Jan  8 2013,rst cause:4, boot mode:(1,3)

wdt reset

  If you want to find the origin of your problem, you can disassemble the .out elf file that has been produced during compilation. To do it, just type:


C:\ESP8266\ESP8266windev\xtensa-lx106-elf\bin\xtensa-lx106-elf-objdump.exe -d esp8266_at.out >disassemble.txt


Now find 40245f15 and you will see where the error appears.

2 thoughts on “ESP8266 Fatal exception”

  1. I experienced this problem too.
    The solution for me (using Arduino 1.6.8 IDE) was to change the flash size from the default of 512k to 1M. The flash size can be found by issuing the ESP8266 AT commands in a serial terminal (before you try to flash it with custom firmware). Don’t remember the exact ones, but AT should return OK, AT+RST should reset the module, and AT+GMR prints the version. Each command must be followed by CR/LF pair. Lots of luck.

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