ESP8266 Community Forum

Posted: **Sun Apr 26, 2015 12:24 pm**

Hi!

Some files (e.g. css / png) when trying to serve cause Fatal exception (28).

Con req, conn=0x3fff6040, pool slot 0
Fatal exception (28):
epc1=0x40106d24, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
rm match
del if0
bcn 0
del if1
usl
sul 0 0

 ets Jan  8 2013,rst cause:4, boot mode:(1,6)

wdt reset

File size is e.g. 4 - 10 kb so I assume that the memory is not a reason.
What can cause the problem?

Thanks,
Patriko

Posted: **Sun Apr 26, 2015 6:26 pm**

Could you upload one of the offending files and/or the resulting espfs file somewhere so I can take a look at this? Also, is this with the latest version of the code in the spritesserver git repository?

Posted: **Wed May 27, 2015 1:46 pm**

Just for reference:

28 means "LoadProhibitedCause"
"A load referenced a page mapped with an
attribute that does not permit loads [Region
Protection Option or MMU Option]"

Epc1 is the program counter where the exception occured and excvaddr is the address accessed.
Using the mapfile from the linker you typically can pinpoint the function of the problem and using objdump
you can locate the exact code position in c Code.

Hope that helps in the future,
Cal

Posted: **Mon Aug 29, 2016 4:37 pm**

I have recieved following error.

Code: Select all

MQTT Broker Unreachable!!
TCP connection closing
MQTT closed previous connection
MQTT start connection
Fatal exception 28(LoadProhibitedCause):
epc1=0x4022b5cf, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000010, depc=0x00000000

Following is the correesponding app0.map values

Code: Select all

                0x4022aca8                wpa_auth_uses_mfp
 *fill*         0x4022acb6        0x2 
 .irom0.text    0x4022acb8     0x14c0 c:/espressif/ESP8266_SDK/lib\libwpa.a(wpa.o)
                               0x16e8 (size before relaxing)
                0x4022bc44                wpa_sm_rx_eapol
                0x4022bdbc                wpa_register

I am attaching the objdump and .map files. Can please tell the steps to find out what causes error? This will really help everyone.

ESP8266 Community Forum

Fatal exception (28) when serving certain files.

Fatal exception (28) when serving certain files.

Re: Fatal exception (28) when serving certain files.

Re: Fatal exception (28) when serving certain files.

Re: Fatal exception (28) when serving certain files.