PA-II crashes continually with Exception 29

I need help troubleshooting why my PA-II-Flex is in a crash loop.

My PA-II has been working intermittently for several months now. I thought it was a poor wifi connection, but I’ve investigated it more thoroughly with the PurpleAir Utility and the logs show that it keeps crashing every few minutes with Exception (29):

  1 append 20240818.csv
  2 
  3 10:28:50.561 -> 2024/08/18t14:28:50z,c4:5b:be:ea:c2:a3,7.04,3.0+openlog+31954 mb+rv3028+bme68x+pmsx003-a+pmsx003-b,8    1,45,58,979.95,nan,23064,-54,132,2.91,4.86,7.56,2.91,4.86,7.56,20,20,832.81,230.67,39.14,5.51,4.23,2.16,2.89,4.27,5.    78,2.89,4.27,5.78,18,18,755.87,211.42,35.56,4.02,1.49,0.24,nan␚␚␚append 20240818.log
  4 10:28:51.591 -> exception (29):
  5 10:28:51.591 -> epc1=0x4022a6fc epc2=0x00000000 epc3=0x00000000 excvaddr=0x00000404 depc=0x00000000
  6 10:28:51.624 ->
  7 10:28:51.624 -> >>>stack>>>
  8 10:28:51.624 ->
  9 10:28:51.624 -> ctx: cont
 10 10:28:51.624 -> sp: 3ffff5d0 end: 3fffffc0 offset: 01a0
 11 10:28:51.624 -> 3ffff770:  3fffa20c 3fffac7c 00000101 4023db7e

snip

143 10:28:52.190 -> 3fffffb0:  feefeffe feefeffe 3ffe8704 40101ded
144 10:28:52.190 -> <<<stack<<<
145 10:28:52.190 ->
146 10:28:52.190 -> last failed alloc call: 4023ce8e(2056)
147 10:28:52.190 ->
148 10:28:52.190 ->  ets jan  8 2013,rst cause:1, boot mode:(3,7)
149 10:28:52.223 ->
150 10:28:52.223 -> load 0x4010f000, len 1384, room 16
151 10:28:52.223 -> tail 8
152 10:28:52.223 -> chksum 0x2d
153 10:28:52.223 -> csum 0x2d
154 10:28:52.223 -> v8b899c12
155 10:28:52.223 -> ~ld
156 10:28:52.488 ->
157 10:28:52.488 ->
158 10:28:52.488 -> 7.04
159 10:28:52.522 ->  0h00:00.289 1970/01/01t08:00:00z: spiffs active
160 10:28:56.176 ->  0h00:03.963 2024/08/18t14:28:56z: c4:5b:be:ea:c2:a3

A full log shown is at the end of this message.

Steps I’ve taken:

  • erased all the memory
  • re-flashed the firmware
  • moved PA closer to the wifi router
  • unplugged the BME680
  • unplugged the particle sensors
  • removed the SD card

and still the same result: crashing with Exception (29)

Can you help me diagnose this problem?

Thanks,

Charlie

Edit 2024-08-18: better logs (no screenshots), clarify diagnosis steps already taken.

10:28:50.561 -> 2024/08/18t14:28:50z,c4:5b:be:ea:c2:a3,7.04,3.0+openlog+31954 mb+rv3028+bme68x+pmsx003-a+pmsx003-b,81,45,58,979.95,nan,23064,-54,132,2.91,4.86,7.56,2.91,4.86,7.56,20,20,832.81,230.67,39.14,5.51,4.23,2.16,2.89,4.27,5.78,2.89,4.27,5.78,18,18,755.87,211.42,35.56,4.02,1.49,0.24,nan␚␚␚
append 20240818.log

10:28:51.591 -> exception (29):
10:28:51.591 -> epc1=0x4022a6fc epc2=0x00000000 epc3=0x00000000 excvaddr=0x00000404 depc=0x00000000
10:28:51.624 -> 
10:28:51.624 -> >>>stack>>>
10:28:51.624 -> 
10:28:51.624 -> ctx: cont
10:28:51.624 -> sp: 3ffff5d0 end: 3fffffc0 offset: 01a0
10:28:51.624 -> 3ffff770:  3fffa20c 3fffac7c 00000101 4023db7e  
10:28:51.624 -> 3ffff780:  3fff2478 00000ecf 00000ecf 4021acd4  
10:28:51.624 -> 3ffff790:  3fffacac 3fffac94 00000080 00000000  
10:28:51.624 -> 3ffff7a0:  0000000c 3fffa19c 00000081 00000081  
10:28:51.624 -> 3ffff7b0:  00000000 00000001 00000001 4023d114  
10:28:51.657 -> 3ffff7c0:  3fffac64 3fffa19c 00000000 000000ff  
10:28:51.657 -> 3ffff7d0:  3fffac7c 00000101 3fffac7c 000000ff  
10:28:51.657 -> 3ffff7e0:  3fffac7c 3fffa19c 3fffa19c 4023de41  
10:28:51.657 -> 3ffff7f0:  00000002 00000001 3ffffc7c 4023cf34  
10:28:51.657 -> 3ffff800:  00000200 00000200 3fffb164 3fffac34  
10:28:51.657 -> 3ffff810:  3fff94ec 00000200 3fffa19c 4023efed  
10:28:51.657 -> 3ffff820:  3fffb164 3fff71b4 00000003 40242cfe  
10:28:51.657 -> 3ffff830:  00000000 00000080 00000005 00000000  
10:28:51.691 -> 3ffff840:  00000200 3fff7d20 3ffffc7c 4024318f  
10:28:51.691 -> 3ffff850:  3fff71b4 3fffb164 3ffe9636 40243021  
10:28:51.691 -> 3ffff860:  3fff94ac 0000000b 00000003 40242ec6  
10:28:51.691 -> 3ffff870:  4023afb1 3fff94ac 3fff7d20 00000000  
10:28:51.691 -> 3ffff880:  00000004 3fff94ac 3fff7d20 4023b099  
10:28:51.691 -> 3ffff890:  00000300 00000000 56d43e00 deb3d18b  
10:28:51.691 -> 3ffff8a0:  c41acc61 a766af7c 4bc6c46f 46720e31  
10:28:51.691 -> 3ffff8b0:  5d8ea544 b523dcdc 1ea02030 1a861ca0  
10:28:51.821 -> 3ffff8c0:  70747468 632f2f3a 696b702e 6f6f672e  
10:28:51.821 -> 3ffff8d0:  2f722f67 632e3172 13306c72 1d550306  
10:28:51.821 -> 3ffff8e0:  300c0420 0608300a 0c816706 80010201  
10:28:51.821 -> 3ffff8f0:  00000000 b8170000 00000000 00000d01  
10:28:51.821 -> 3ffff900:  688a2180 0000001b 41daf648 00000e01  
10:28:51.821 -> 3ffff910:  688a2180 0000001b 4236bf0b 00000f01  
10:28:51.821 -> 3ffff920:  00000000 00000000 00000000 00000000  
10:28:51.821 -> 3ffff930:  00000000 00000000 00000000 00000000  
10:28:51.821 -> 3ffff940:  00000000 00000000 00000000 00000000  
10:28:51.821 -> 3ffff950:  00000000 00000000 00000000 00000000  
10:28:51.821 -> 3ffff960:  00000002 00000000 00000020 4010267a  
10:28:51.821 -> 3ffff970:  3ffe9e92 40105a64 3ffed600 00000000  
10:28:51.821 -> 3ffff980:  00000001 40104c87 3ffee058 00000000  
10:28:51.821 -> 3ffff990:  401050ea 00000000 00000000 00000000  
10:28:51.821 -> 3ffff9a0:  00000000 00000000 00000000 00000000  
10:28:51.821 -> 3ffff9b0:  40104bce 0000002c 7fffffff 00000002  
10:28:51.821 -> 3ffff9c0:  0000012c 00000061 3fff4ec8 00000001  
10:28:51.821 -> 3ffff9d0:  40103a43 00080000 03eb032b 78142d00  
10:28:51.821 -> 3ffff9e0:  00000000 66c60012 00002200 4000050c  
10:28:51.821 -> 3ffff9f0:  3fffc278 40103740 3fffc200 00000022  
10:28:51.821 -> 3ffffa00:  3ffffa10 00000000 3ffe9fe1 00000008  
10:28:51.821 -> 3ffffa10:  00000002 00000000 00000020 4010267a  
10:28:51.821 -> 3ffffa20:  3ffe9e92 40105a64 3ffed600 00000001  
10:28:51.821 -> 3ffffa30:  00000001 40104c87 3ffee058 3ffffbc9  
10:28:51.821 -> 3ffffa40:  401050ea 4026e744 3ffffbf3 3fff092b  
10:28:51.821 -> 3ffffa50:  00000002 00000000 00000020 4010267a  
10:28:51.821 -> 3ffffa60:  3ffe9e92 40105a64 3ffed600 00000002  
10:28:51.821 -> 3ffffa70:  00000001 40104c87 3ffee058 3fff48b4  
10:28:51.821 -> 3ffffa80:  401050ea 00080000 00000000 0000001b  
10:28:51.821 -> 3ffffa90:  00000000 4022f001 00002200 4000050c  
10:28:51.848 -> 3ffffaa0:  40104bce 0000002b 4025bd57 00000001  
10:28:51.848 -> 3ffffab0:  ffffffff 00000000 3ffe9fe1 00000008  
10:28:51.848 -> 3ffffac0:  4025bda6 3ffed628 3fff3724 00000001  
10:28:51.848 -> 3ffffad0:  4025beb2 3ffed628 3fff3724 3ffed628  
10:28:51.848 -> 3ffffae0:  00000005 00000005 00000008 3fff94c8  
10:28:51.848 -> 3ffffaf0:  3ffe9e92 4025ae4f 3ffed628 3fff4824  
10:28:51.848 -> 3ffffb00:  00000000 402479bf 3ffeeab8 ffffffff  
10:28:51.859 -> 3ffffb10:  00000000 00000002 00000000 3ffed628  
10:28:51.859 -> 3ffffb20:  3fff94e2 40106107 3fff4824 3fff48b4  
10:28:51.891 -> 3ffffb30:  3fff94ac 00000080 00000001 3fff350c  
10:28:51.891 -> 3ffffb40:  3fff70b0 4022f001 3fff24b0 3fff48b4  
10:28:51.891 -> 3ffffb50:  3fff94e2 00000036 401039a6 00000100  
10:28:51.891 -> 3ffffb60:  00000140 00000000 39d4a599 00fd3562  
10:28:51.891 -> 3ffffb70:  61e046dc 38707192 1ca03f03 52c00f50  
10:28:51.891 -> 3ffffb80:  f757a8ba 77db7281 966b25b5 45811d72  
10:28:51.891 -> 3ffffb90:  c469866f 4c78e6e4 7fa1e631 0a7301a7  
10:28:51.891 -> 3ffffba0:  8987ef87 c5d3cc72 0103028d 00800100  
10:28:51.924 -> 3ffffbb0:  00000000 00000000 00000000 00000000  
10:28:51.924 -> 3ffffbc0:  00000000 30090000 e251cb7d af593104  
10:28:51.924 -> 3ffffbd0:  5a804545 a0f45bc2 26a0bd76 00000000  
10:28:51.924 -> 3ffffbe0:  00000000 00000000 00000000 00000000  
10:28:51.924 -> 3ffffbf0:  00000000 00000000 00000000 00000000  
10:28:51.924 -> 3ffffc00:  00000000 00000000 00000000 00000000  
10:28:51.924 -> 3ffffc10:  00000000 00000000 00000000 00000000  
10:28:51.957 -> 3ffffc20:  00000000 00000000 003ed456 8bd1b3de  
10:28:51.957 -> 3ffffc30:  61cc1ac4 7caf66a7 6fc4c64b 310e7246  
10:28:51.957 -> 3ffffc40:  44a58e5d dcdc23b5 00000000 40236c74  
10:28:51.957 -> 3ffffc50:  b77c3ffc dea68f9a 5dd88da2 3fff70ac  
10:28:51.957 -> 3ffffc60:  3fff70b0 3fff94ac 00000210 00000243  
10:28:51.957 -> 3ffffc70:  00000000 00000002 00000566 00000316  
10:28:51.957 -> 3ffffc80:  00000452 00000002 40217bb4 3fffefa0  
10:28:51.957 -> 3ffffc90:  000000f0 3fff3fb4 00002710 40217c96  
10:28:51.991 -> 3ffffca0:  00000000 000001fa 00000000 40217cd9  
10:28:51.991 -> 3ffffcb0:  40238cc4 0000000c 00000a4f 00000002  
10:28:51.991 -> 3ffffcc0:  3fff3fb4 3fff72d1 00000a4f 40238b91  
10:28:51.991 -> 3ffffcd0:  00000fae 3fff71f4 00000fb5 3fff3fac  
10:28:51.991 -> 3ffffce0:  3fff5d0c 00000007 00860011 3fff7248  
10:28:51.991 -> 3ffffcf0:  00000566 12202e45 2d53179d b9569dde  
10:28:51.991 -> 3ffffd00:  a8a92f8b 3fff8e5c 5dd88c0c 00000fb5  
10:28:51.991 -> 3ffffd10:  3fff72d1 00000fb5 3fff71f4 4023a2b3  
10:28:52.024 -> 3ffffd20:  1f093dc9 2d1d3155 5c52cf96 0a56b333  
10:28:52.024 -> 3ffffd30:  2856f8fe 00000584 3fff70ac 4022fa89  
10:28:52.024 -> 3ffffd40:  0000003d 3fff826a 3fff826a 3fff8e5c  
10:28:52.024 -> 3ffffd50:  00000000 00000f5c 00000064 40217c96  
10:28:52.024 -> 3ffffd60:  00000000 00000020 00000027 00000fb5  
10:28:52.024 -> 3ffffd70:  3fff72d1 00000fb5 3fff71f4 00000fb5  
10:28:52.024 -> 3ffffd80:  3fff72d1 00000fb5 3fff71f4 40239c9c  
10:28:52.024 -> 3ffffd90:  572765aa 00000000 00000000 00000028  
10:28:52.057 -> 3ffffda0:  0000005d 3fff72d1 3fff71f4 4023a06c  
10:28:52.057 -> 3ffffdb0:  00000011 3fff7304 000001f4 4021af18  
10:28:52.057 -> 3ffffdc0:  3ffffe18 0000000b 00000010 3fff5de4  
10:28:52.057 -> 3ffffdd0:  00000000 00000000 4bc6a7f0 01000000  
10:28:52.057 -> 3ffffde0:  3ffffe18 00020a33 3fff71f4 40239e04  
10:28:52.057 -> 3ffffdf0:  00000000 402712e2 3ffffe10 3fff5de4  
10:28:52.057 -> 3ffffe00:  3fff5c84 00020a33 3fff6ef4 40211655  
10:28:52.057 -> 3ffffe10:  3fff71f4 3fff5f14 00000014 4022eed2  
10:28:52.090 -> 3ffffe20:  00008ca0 3ffffe50 3fff0e58 40211694  
10:28:52.090 -> 3ffffe30:  00000000 00000000 3fff0e40 000001bb  
10:28:52.090 -> 3ffffe40:  000001bb 402712e2 3fff0e40 402118a3  
10:28:52.090 -> 3ffffe50:  00000000 00000000 4bc6a7f0 000001bb  
10:28:52.090 -> 3ffffe60:  000001bb 402712e2 3fff0e40 4021195a  
10:28:52.090 -> 3ffffe70:  402213a8 d3bdfa8e 402213a8 d3bdfa8e  
10:28:52.090 -> 3ffffe80:  3fff0cc8 3fff0e40 3fff0509 4020c83a  
10:28:52.090 -> 3ffffe90:  3fff0509 00000000 3ffe8de2 40229904  
10:28:52.124 -> 3ffffea0:  4026397a 3fff0921 3fff10c4 00000003  
10:28:52.124 -> 3ffffeb0:  4020f9e0 3ffffee8 3fff10c4 4022651d  
10:28:52.124 -> 3ffffec0:  40271390 0000000a 3fffff68 3fffff6c  
10:28:52.124 -> 3ffffed0:  3fffff70 3fff42fc 00000001 40203fbf  
10:28:52.124 -> 3ffffee0:  402213a8 00000000 402213a8 00000000  
10:28:52.124 -> 3ffffef0:  402712e2 000001bb 3fff0921 40206605  
10:28:52.124 -> 3fffff00:  3fffff74 402712e2 000001bb 00000001  
10:28:52.157 -> 3fffff10:  3ffe8e05 3fff0509 00000200 00000000  
10:28:52.157 -> 3fffff20:  3ffe8e05 00000001 3ffefd51 00000002  
10:28:52.157 -> 3fffff30:  00000001 00000001 3ffe8e05 0000000a  
10:28:52.157 -> 3fffff40:  7fffffff 3ffefd30 3ffefdb8 3fff226c  
10:28:52.157 -> 3fffff50:  3fffdad0 3fff0c4b 3ffefd30 40208ec8  
10:28:52.157 -> 3fffff60:  3ffe8e05 0000000a 00000000 4020983c  
10:28:52.157 -> 3fffff70:  40205458 4020904c 40217bb4 3fffefa0  
10:28:52.157 -> 3fffff80:  00000000 00000000 3fff0c82 40217c96  
10:28:52.190 -> 3fffff90:  3fffdad0 00000000 3fff0c82 4020b8f8  
10:28:52.190 -> 3fffffa0:  3fffdad0 00000000 3fff223c 40217c64  
10:28:52.190 -> 3fffffb0:  feefeffe feefeffe 3ffe8704 40101ded  
10:28:52.190 -> <<<stack<<<
10:28:52.190 -> 
10:28:52.190 -> last failed alloc call: 4023ce8e(2056)
10:28:52.190 -> 
10:28:52.190 ->  ets jan  8 2013,rst cause:1, boot mode:(3,7)
10:28:52.223 -> 
10:28:52.223 -> load 0x4010f000, len 1384, room 16 
12:28:52.223 -> tail 8
10:28:52.223 -> chksum 0x2d
10:28:52.223 -> csum 0x2d
10:28:52.223 -> v8b899c12
10:28:52.223 -> ~ld
10:28:52.488 -> 
10:28:52.488 -> 
10:28:52.488 -> 7.04
10:28:52.522 ->  0h00:00.289 1970/01/01t08:00:00z: spiffs active
10:28:56.176 ->  0h00:03.963 2024/08/18t14:28:56z: c4:5b:be:ea:c2:a3
10:28:56.176 ->  0h00:03.965 2024/08/18t14:28:56z: ssid: ssidxxx␚␚␚␚␚␚disk
ls
append 20240818.csv
␚␚␚append 20240818.log
␚␚␚disk
ls
append 20240818.csv

10:31:04.980 -> 2024/08/18T14:31:04z,c4:5b:be:ea:c2:a3,7.04,3.0+OPENLOG+31954 MB+RV3028+BME68X+PMSX003-A+PMSX003-B,81,44,57,979.96,nan,18552,-51,132,2.98,4.17,4.71,2.98,4.17,4.71,17,17,733.71,208.90,27.71,1.62,0.71,0.62,3.20,4.84,5.71,3.20,4.84,5.71,20,20,756.27,219.96,35.04,3.71,1.33,0.38,nan␚␚␚append 20240818.log
10:31:06.010 -> Exception (29):
10:31:06.010 -> epc1=0x4022a6e2 epc2=0x00000000 epc3=0x00000000 excvaddr=0x00000008 depc=0x00000000
10:31:06.010 -> 
10:31:06.010 -> >>>stack>>>
10:31:06.010 -> 
10:31:06.010 -> ctx: cont
10:31:06.010 -> sp: 3ffff640 end: 3fffffc0 offset: 01a0
10:31:06.043 -> 3ffff7e0:  3fffb504 3fffb47c 3fffb47c 4023de10  
10:31:06.043 -> 3ffff7f0:  00000002 00000001 3ffffc7c 4023cf34  
10:31:06.043 -> 3ffff800:  00000200 00000200 3fffb9ac 3fffb4d4  
10:31:06.043 -> 3ffff810:  3fff5c44 00000200 3fffb47c 4023efed