I disassembled the device only after it stopped working. Serial connection is ok.
Messages go cyclically(i delete just MAC):
ShowCritical:1
ets Jan 8 2013,rst cause:4, boot mode:(3,7)
wdt reset
load 0x40100000, len 2408, room 16
tail 8
chksum 0xe5
load 0x3ffe8000, len 776, room 0
tail 8
chksum 0x84
load 0x3ffe8310, len 632, room 0
tail 8
chksum 0xd8
csum 0xd8
2nd boot version : 1.6
SPI Speed : 80MHz
SPI Mode : QIO
SPI Flash Size & Map: 32Mbit(1024KB+1024KB)
jump to run user2 @ 101000
r#βββc
ββ#$cββc|βdΔdcββgββ
βββ
dβ
β
d
dlββββ$βnβββββc llβ{βcββββc dβbβlsdββββoβ;ββg|β lld$
β
ets Jan 8 2013,rst cause:4, boot mode:(3,7)
wdt reset
load 0x40100000, len 2408, room 16
tail 8
chksum 0xe5
load 0x3ffe8000, len 776, room 0
tail 8
chksum 0x84
load 0x3ffe8310, len 632, room 0
tail 8
chksum 0xd8
csum 0xd8
2nd boot version : 1.6
SPI Speed : 80MHz
SPI Mode : QIO
SPI Flash Size & Map: 32Mbit(1024KB+1024KB)
jump to run user2 @ 101000
?{ββcβββcββcdcββ#|rβlββlbββoβββββββlββlldβΔβdβ'ββββcllβ{βc βββc lβ#β$sdβββnβ{ββo|βl$ld
βmode : sta(MAC)
add if0
ShowCritical:1
ets Jan 8 2013,rst cause:4, boot mode:(3,7)
wdt reset
load 0x40100000, len 2408, room 16
tail 8
chksum 0xe5
load 0x3ffe8000, len 776, room 0
tail 8
chksum 0x84
load 0x3ffe8310, len 632, room 0
tail 8
chksum 0xd8
csum 0xd8
2nd boot version : 1.6
SPI Speed : 80MHz
SPI Mode : QIO
SPI Flash Size & Map: 32Mbit(1024KB+1024KB)
jump to run user2 @ 101000
sβcβββbββbl#βββc|;β$ββlcββββogβ
βββ$ββ
$
llβ
ββββl βgββββb$
dβsβ
ββbl
βcβd;lβββgβsββn|β$
dll`βShowCritical:1
ets Jan 8 2013,rst cause:4, boot mode:(3,7)
wdt reset
load 0x40100000, len 2408, room 16
tail 8
chksum 0xe5
load 0x3ffe8000, len 776, room 0
tail 8
chksum 0x84
load 0x3ffe8310, len 632, room 0
tail 8
chksum 0xd8
csum 0xd8
2nd boot version : 1.6
SPI Speed : 80MHz
SPI Mode : QIO
SPI Flash Size & Map: 32Mbit(1024KB+1024KB)
jump to run user2 @ 101000
~;βcβββc
ββcdcββ#<βlββlcββoβββββββlβ
βl
l$ββββd`βoβΔβ#
d
dβrβ
βββ#$
βcβl{lβββgββsβββ|β
d
l$l β
ets Jan 8 2013,rst cause:4, boot mode:(3,7)
wdt reset
load 0x40100000, len 2408, room 16
tail 8
chksum 0xe5
load 0x3ffe8000, len 776, room 0
tail 8
chksum 0x84
load 0x3ffe8310, len 632, room 0
tail 8
chksum 0xd8
csum 0xd8
2nd boot version : 1.6
SPI Speed : 80MHz
SPI Mode : QIO
SPI Flash Size & Map: 32Mbit(1024KB+1024KB)
jump to run user2 @ 101000
{ββcβββbββclbββc|;β$ββl#ββnβogββββ$ββ$
ldβ
ββββlβ'ββββcllβ{βc βββc lβ#β$sdβββnβ{ββo|βllld
βmode : sta(MAC)
add if0
ShowCritical:2
ets Jan 8 2013,rst cause:4, boot mode:(3,7)
wdt reset
load 0x40100000, len 2408, room 16
tail 8
chksum 0xe5
load 0x3ffe8000, len 776, room 0
tail 8
chksum 0x84
load 0x3ffe8310, len 632, room 0
tail 8
chksum 0xd8
csum 0xd8
2nd boot version : 1.6
SPI Speed : 80MHz
SPI Mode : QIO
SPI Flash Size & Map: 32Mbit(1024KB+1024KB)
jump to run user2 @ 101000
sβcβββ#Δbl#βββc|{βdββ$cββββngβ
βββdββ
d
$lβ
ββββl βgββββbl
dβsβ
βββclβcβd;lβββββ{ββn<β$
dld`βShowCritical:1