ESP8266 Community Forum

- Mon Apr 27, 2015 11:38 am #15812 Moin,

I managed to get some more info in case of a boot failure (fatal exception 29) aka zombie mode.

For the impatient:
That means the code in memory is not as expected!

Details:

Code: Select allcal_dex 0.2a, dump 0.2a
Fatal Exception: 001d (29), sp 3ffffad0
SDK Version: 0.9.5
Fingerprint: 1/xh=4023fb8c,t=0000-7da4,d=8000-8b48,b=ca70-5350,ro=8b50-ca70
 epc1: 402228c8  exccause: 0000001d  excvaddr: 00000044  depc: 00000000
 ps  : 00000030  sar     : 00000019  unk1    : 80899bc3
 a0 :  4021f72f  a1 :  3ffffbd0  a2 :  60000600  a3 :  00000001
 a4 :  00000002  a5 :  3ffecf94  a6 :  03910267  a7 :  01910267
 a8 :  00000010  a9 :  01910267  a10:  00000004  a11:  00000000
 a12:  60000600  a13:  00000001  a14:  60000e00  a15:  3ffecdd8
Stack (3ffffbb0)
3ffffb90  40100860 3ffffbd0 f854dadd e13d1b52 3ffffbd0 3ffffbd0 00000004 9cc74050
3ffffbb0  000000d0 00000043 3ffffbd0 00000018 3fff54f0 4021fab9 3ffecf8a 9c02b254
3ffffbd0  00100000 0019c06a 4021f794 00000000 4021fb4b 60000e78 402199f9 0000007d
3ffffbf0  00000000 0000000e 4021009f 3ffeca96 3ffeca96 00000000 00000000 00000000
3ffffc10  00000000 3fff5450 40210473 3ffeca9c 402104ba 3fff5460 40210495 3fff5460
3ffffc30  00000000 400042db 73bcc810 2cef3292 40004b31 0007c000 00000002 40100340
3ffffc50  0007c000 00000002 d6d3c977 bf981f0b ffffffff ffffffff ffff0001 00000004
3ffffc70  6b6e7570 00000000 00000000 00000000 00000000 00000000 00000000 00000000
3ffffc90  00030503 21000001 63696572 33317368 72616d36 0000216b 00000000 00000000
3ffffcb0  00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
3ffffcd0  00000000 00000000 a6251cf8 a65db399 e38fc234 f9cd095d 4b8c072d d3520bcc
3ffffcf0  b5074eb3 77daaea2 ffffff01 ffffffff ffffffff ffffffff ffff00ff ffffffff
3ffffd10  00000011 542d4941 4b4e4948 395f5245 38393844 00000035 00000000 00000000
3ffffd30  00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
3ffffd50  00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
3ffffd70  00000000 ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff
3ffffb90 40100860
3ffffbc4 4021fab9
3ffffbd8 4021f794
3ffffbe0 4021fb4b
3ffffbe8 402199f9
3ffffbf8 4021009f
3ffffc18 40210473
3ffffc20 402104ba
3ffffc28 40210495
3ffffc34 400042db
3ffffc40 40004b31
3ffffc4c 40100340
3fffffd4 4010000c
3fffffd8 40001878
3fffffe0 40001100
3ffffff0 4000044c
epc1:
40222888  520020c0 5580d026 20557010 520020c0 020cd066 00ffe446 66021226 18512f22
402228a8  010522ff 632162ec 0020c0b6 304a2232 a3cc1430 420020c0 40404a22 40404a22
402228c8  40404a22 40404a22 40404a22 40404a22 40404a22 40404a22 0020c0b6 0c446682
402228e8  0020c007 51516672 20c0c234 40665200 c0e8d441 23220020 102240f2 220020c0


The most interesting part is the dump of the epc1 block.
epc1 is the programm counter (pc) where the exception occurred. (Note that the integer values are little endian,
so some mental byte swapping needed when looking at the code.

The content of the address 402228c8 is 40404a22.

But it should be (as dumped on startup)

Code: Select all402228c8  20c0270c 4a226200 62106670 f00d0345 31e65b81 5761e1b8 0020c0b6 0c446682

For code

Code: Select all402228c8:       270c            movi.n  a7, 2
402228ca:       0020c0          memw
402228cd:       4a2262          l32i    a6, a2, 0x128


That means the code in memory is not as expected!

Cal

Get your modules here:

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

- Mon Apr 27, 2015 12:01 pm #15814 Please read !!!!

The reason for Zombie Mode, is because that the RTC checksum is not completely written, before deepsleep !
http://bbs.espressif.com/viewtopic.php?f=7&t=205&start=10#p875

Thanks and best regards.

- Mon Apr 27, 2015 12:18 pm #15817 Moin,

as I understand the link:

"MEM CHECK FAIL" actually means "the Sleep parameters stored in RTC memory are broken and then the firmware will restore the parameters as the default values".
So it is actually a warning, and is useful only when waking up from deep-sleep.

[quote2) If you push the reset button when CPU is running, this warning text will be printed.
because the checksum may have been not updated.
And the firmware will not apply the parameters for safe.][/quote]

The RTC data is just not appllied if CRC is not written mut I don't find anything on the link
that talks about the chip not booting.

Nevertheless it may be useful to check with correct rtc set/get functions of a newer SDK.
The 0.9.5 version of those a broken.

Cal

Get your modules here:

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

- Mon Apr 27, 2015 12:59 pm #15823 I did a really brute force short test using parts of the libmain.a of esp-opensdk:

esp-open-sdk/esp_iot_sdk_v1.0.0/lib/libmain.a (105626 bytes)

In short I extracted user_interface.o from that lib,
removed user_interface.o from nodemcu libmain.a and added the extraction above.
Added fake symbols for the 2 link errors and nodemcu started OK and runs for 20 minutes now
without a crash. Can't test any longer now.

Maybe we should concentrate on making nodemcu usable with latest SDK to avoid fighting ghosts?
From what I understood from comments I read the main reason for not using it is less free memory?
But at some time that problem has to be solved anyway.

Cal

Get your modules here:

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