Guru Meditation Error & Magnetic Interference (EMI/RFI)

[combaindeft]

Hi all,

I've run into the same "Guru Meditation Error" issue with our "PySense + FiPy" and "PyTrack + FiPy's" ...

Though the weirdest thing is, it wasn't running any code ... freshly firmware'd ... both boards to version 8 ... and the FiPy's to 1.18.r7 ...

We where doing some field tests ... and the devices just ran in an endless "Guru Meditation Error" & "Core dump" loop ... noticed we where close to a BIG Power Line(s) ... so we choose to just drive a bit further away ... and wham ... it stopped!

Drove back towards the same spot ... and wham ... the board just ran in an endless loop "Guru Meditation Error" ...

Drove away again ... and wham ... it stopped!

So my question is: how sensitive to magnetic interference (EMI/RFI) are all of PyCom's products?? @robert-hh @Paul-Thornton

And follow-up question: What type of shielding should one use? (like a case? or foil to place inside an exciting case?)

[Martinnn]

Interesting... would be nice to see your setup! I doubt magnetic interference could be an issue (but who knows, you write BIG power lines...). In EMC compliance testing, there isn't even a test for magnetic immunity. Of course there is electromagnetic immunity, but the biggest influence will come from the connecting cables (unless you run on battery), acting as antennas and picking up all kind of noise.
Now that you say it I also think that I get guru errors only from USB connected devices. I have a couple of wipys running standalone with wall plug supply which as far as I remember seem to do fine. Of course you would not see the guru message in an unconnected standalone setup.

[combaindeft]

@martinnn @Paul-Thornton

Scenarios we ran:

A) With USB-cable

• As soon as it started to happen, we unplugged it ... but the device wouldn't come back to life ... it just ran around in an endless "Guru Meditation Error" & "Core Dump" loop ...

• Tested different cables to ... since there are "good shielded usb cables" and then there are "GOOOD shielded usb cables" ... neither helped.

• Only driving a bit farther away helped ...

B) No-USB--Cable

• Since we programmed in different RGB Led Colours into the code sequence ... we could simply by looking at it know what it was doing / supposed to do...

• Not even the "Heartbeat" (blue flashing color) come to life ... and since we knew what colors to expect when it ran the code ... it was quite easy to come to the conclusion that it was running around in an endless "Guru Meditation Error" & "Core Dump" loop too ...

• We could confirm that it was, by swiftly hooking it up with a USB-Cable, that it was indeed in the Guru-Core-Dump-Loop

• and yes, we did unplug the battery too, reset it in every conceived possible way ... though only driving a bit farther away helped ...

NOTE: In booth Scenarios, we ran with our own code ... and freshly reset-and-firmwared (no code running, as we wanted to exclude that it wasn't our code that was bonkers) ...and as soon as we left the area ... they just booted back up and ran the code ... or was just idling with the "Heartrate" led flashing ...

PS: We will do some more field testing tomorrow .... and we shall document with logs and images / video this issue.

[Paul Thornton]

@combaindeft Thanks for the report and the investigation work. Ill raise this with the team as something to look into. clearly this shouldnt be an issue.

[Paul Thornton]

Hi @combaindeft

It would be usefull if at all possible to get the output of some of the core dumps when its in its issue state. You can post there here or email them to paul@pycom.io,

Thanks :)

[combaindeft]

@paul-thornton okidokeli-do :-)

After tomorrows field test I'll do that.

[Paul Thornton]

@combaindeft Thanks. much appreciated :)

[Martinnn]

@combaindeft It would be really interesting to know what type of environment you have. At 100 kW radio transmitter? Inside a nuclear reactor?
Generally I'd say the Wipy (or any other module) is not "CE compliant" in a product sense - obviously any ESD event will kill the device instantly. That's OK because it is a component. If you build a product with it, it is your responsability to make sure the relevant EMC regulation requirements are fullfilled (usually by getting a certificate from a test lab). Pycom provides RED certificates here: https://docs.pycom.io/documents/certificates.html - but this is RED only (the radio part). Anything else (ESD, conducted, magnetic...) is up to you. So if you choose to operate this component inside an MRI machine, it is your responsability to provide adequate shielding. Of course Pycom can make your job easier or more difficult by providing a design that is super sensitive and resets with the lightest disturbance or one that is extremely robust. But in the end you put the CE mark on your product!
However, even fullfilling the relevant CE immunity requirements will not make sure your product works everywhere. EMC limits are set so that most devices interoperate reasonbly. That means if you switch on a kitchen blender, the TV won't go black. You take that TV inside a HVDC plant and probably it won't survive that - which is OK, because nobody lives there and that requirement would make a TV ridiculously expensive.
So if you want your design to work at a specifically nasty environment, it seems you have to learn something about EMC/EMI...
BTW a friend once told me they built cameras for the Tchernobyl cleanup. They used a picture tube with discrete radiation hard components only, encased in a massive lead block. These lasted a few hours on site before they were destroyed by the radiation. So it all depends...

[crumble]

@martinnn said in Guru Meditation Error & Magnetic Interference (EMI/RFI):

But if you shield the pytrack you have only an expansion board 3 with a reduced amount of pins ;)

[Martinnn]

@crumble that's the challenge. EMC gurus have to make a living too, not just meditating gurus!

[combaindeft]

@martinnn said in [Guru Meditation Error & Magnetic Interference (EMI/RFI)]

@combaindeft It would be really interesting to know what type of environment you have. At 100 kW radio transmitter? Inside a nuclear reactor?

Nothing that fancy, just a place in the middle of Nowhere.

It just happens that there is a High Voltage Power Line crossing it - Map to Field @ Nowhere

Generally I'd say the Wipy (or any other module) is not "CE compliant" in a product sense - obviously any ESD event will kill the device instantly. That's OK because it is a component. If you build a product with it, it is your responsability to make sure the relevant EMC regulation requirements are fullfilled (usually by getting a certificate from a test lab). Pycom provides RED certificates here: https://docs.pycom.io/documents/certificates.html - but this is RED only (the radio part). Anything else (ESD, conducted, magnetic...) is up to you. So if you choose to operate this component inside an MRI machine, it is your responsability to provide adequate shielding. Of course Pycom can make your job easier or more difficult by providing a design that is super sensitive and resets with the lightest disturbance or one that is extremely robust

Yeah, we're not complaining about who's responsible and such ... just as I highlighted in bold ... it would just make it easier if the devices where "more robust" ...

But in the end you put the CE mark on your product!

mmm, and for that step we're going to design something from the ground up ourselves with ...

but for "as close to street product level we can get with development boards" ... it would make it easier for us in our R&D in finding the right solution for the customer ...

Instead of spending more time on playing MacGyver :-)

So if you want your design to work at a specifically nasty environment, it seems you have to learn something about EMC/EMI...

Japp, looks like we're play MacGyver ... it's fun from time to time :-)

[Paul Thornton]

@combaindeft If you happen to see this before your field test. It may be handy if you could install one of the EMF detector style app's for mobiles you can get. they wont be super accurate but it should give us an idea if "something" is going on.

Just grab a couple of reading's at various ranges from the powerline.

[Paul Thornton]

@combaindeft said in [Guru Meditation Error & Magnetic Interference (EMI/RFI)]

Nothing that fancy, just a place in the middle of Nowhere.

It just happens that there is a High Voltage Power Line crossing it - Map to Field @ Nowhere

Yeah thats pretty isolated. Couldnt see anything myself other than the powerlines that could cause it at least with the minimal view streetview gives. presuming there's nothing buried below that field at least :P

[combaindeft]

@paul-thornton

ok, I downloaded these two apps:
EMF Radiation Detector
Electromagnetic Detector EMF

In Sweden, we have most of our power-lines underground ... just a few that go above ground ... like this one ...

As for other things underground ... a thing that hit me was that they might have some ore-deposits in the vicinity that magnifies the effects of the High-Power Line.

[Paul Thornton]

@combaindeft Look forward to seeing your results. this is one of the more unique problem's Ive encountered during my time at pycom and I'd like to see it resolved :)

[crumble]

@combaindeft

As for other things underground ... a thing that hit me was that they might have some ore-deposits in the vicinity that magnifies the effects of the High-Power Line.

Not all power lines behave in the same way. As a former owner of an analog polar system, I had not under all power lines problems. The bicycle computer had two levels of confusion. The higer one was next to tracks near a train station and below a certain power line. Sometimes next to those small transformation buildings.

I assumed that the high level of confusion was related to modulated communication over some of these power lines. The polar used a primitiv protocol without any buffering. So I asumed that the spikes of the communication was parsed as strange values from the reed sensors.

[Martinnn]

@combaindeft Very interesting. I lived once nearly below a 380 kV line.
What does your physical setup look like? Cables, connections...? I honestly doubt that any module alone could be affected by any kind of power line - power lines are 50 Hz mostly, field strength might be something but yours does not look like a 380 kV one. I would suspect that your setup contains some long wires as antenna or worse: loops that pick up some signal.
You write that you use the Pysense. I am also using a pysense/wipy combination and I suspect these are extremely sensitive with a USB cable connected. In my office, I had six of those running on 4.2V (battery connector powered from lab power supply), which are still running (MQTT send every 2s via wifi). Five units are connected via USB (one to my laptop, four to a powered hub), of which three died in the past two days. Same pattern in the days before. I have standalone units running for two weeks now.
So it seems you don't need a power line to make those things fail.
Can you try running the pysense boards without connections? Just add a battery and set them to communicate wirelessly?
@pycom: it seems you might have some work to do regarding the pysense (beyond the poor documentation and missing schematic).

[combaindeft]

@paul-thornton said in Guru Meditation Error & Magnetic Interference (EMI/RFI):

@combaindeft Look forward to seeing your results. this is one of the more unique problem's Ive encountered during my time at pycom and I'd like to see it resolved :)

LOG:

---------- 2019-02-06 20:44:40 +0100: Connected ----------

-----------------------------------------------------------------------------
LOG   :: Loading XYZ
-----------------------------------------------------------------------------
DEBUG :: START-UP                                 :: @ 3  :: FREE MEM 2507104
-----------------------------------------------------------------------------
DEBUG :: ENABLE GC                                :: @ 3  :: FREE MEM 2506768
DEBUG :: IMPORT MACHINE                           :: @ 3  :: FREE MEM 2506432
-----------------------------------------------------------------------------
DEBUG :: IMPORT PyTrack                           :: @ 5  :: FREE MEM 2494080
DEBUG :: IMPORT WDT                               :: @ 5  :: FREE MEM 2493632
DEBUG :: @Getting a Watch Dog
DEBUG :: @Resting Watch Dog for 20 Sec
LOG   :: Define py()
Guru Meditation Error: Core  0 panic'ed (InstrFetchProhibited)
. Exception was unhandled.
Register dump:
PC      : 0x00000000  PS      : 0x00060e30  A0      : 0x8011a4c9  A1      : 0x3ffbd650  
A2      : 0x00000000  A3      : 0x00000037  A4      : 0xffffffa4  A5      : 0x3fbc1e24  
A6      : 0x00000008  A7      : 0x00000000  A8      : 0x801257a4  A9      : 0x3ffbd640  
A10     : 0x3fbc1e40  A11     : 0x00000037  A12     : 0xffffffa4  A13     : 0x3ffbd6e4  
A14     : 0x7777715b  A15     : 0x7777715b  SAR     : 0x00000010  EXCCAUSE: 0x00000014  
EXCVADDR: 0x00000000  LBEG    : 0x4009b2dd  LEND    : 0x4009b311  LCOUNT  : 0xffffffff  

Backtrace: 0x00000000:0x3ffbd650 0x4011a4c6:0x3ffbd670 0x4011b4d3:0x3ffbd740 0x40131a71:0x3ffbd760 0x401335d3:0x3ffbd7b0

================= CORE DUMP START =================
cD0AABAAAABsAQAA
WNj7P5DV+z9Q2Ps/
YNb7P/DX+z8p152hlFL8P5RS/D9Y2Ps/jFL8PwIAAADowfs/6MH7P1jY+z8AAAAA
FwAAAFTI+z93aWZpAPLMRVVZwuIcsYcAAAAAAFDY+z8AAAAAIA4GABcAAAABAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAACEe/0/7Hv9P1R8/T8AAAAAAAAAAAEAAAAAAAAA
81pAPwAAAAAYuglAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAH4hyA==

[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
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================= CORE DUMP END =================
Rebooting...
ets Jun  8 2016 00:22:57

rst:0xc (SW_CPU_RESET),boot:0x17 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:1
load:0x3fff8028,len:8
load:0x3fff8030,len:1728
load:0x4009fa00,len:0
load:0x4009fa00,len:14592
entry 0x400a059c
-----------------------------------------------------------------------------
LOG   :: Loading XYZ
Guru Meditation Error: Core  0 panic'ed (InstrFetchProhibited)
. Exception was unhandled.
Register dump:
PC      : 0x00000000  PS      : 0x00060030  A0      : 0x8011a4c9  A1      : 0x3ffbd650  
A2      : 0x00000000  A3      : 0x00000037  A4      : 0xffffffa5  A5      : 0x3fbc1e28  
A6      : 0x00000008  A7      : 0x00000000  A8      : 0x801257a4  A9      : 0x3ffbd640  
A10     : 0x3fbc1e44  A11     : 0x00000037  A12     : 0xffffffa5  A13     : 0x3ffbd6e4  
A14     : 0x7777715b  A15     : 0x7777715b  SAR     : 0x00000010  EXCCAUSE: 0x00000014  
EXCVADDR: 0x00000000  LBEG    : 0x4009b2dd  LEND    : 0x4009b311  LCOUNT  : 0xffffffff  

Backtrace: 0x00000000:0x3ffbd650 0x4011a4c6:0x3ffbd670 0x4011b4d3:0x3ffbd740 0x40131a71:0x3ffbd760 0x401335d3:0x3ffbd7b0

================= CORE DUMP START =================
sDUAABAAAABsAQAA
WNj7P5DV+z9Q2Ps/
sNb7P/DX+z8p152hlFL8P5RS/D9Y2Ps/jFL8PwIAAADowfs/6MH7P1jY+z8AAAAA
FwAAAFTI+z93aWZpAPLMRVVZwuIcsYcAAAAAAFDY+z8AAAAAIAAGABcAAAABAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAACEe/0/7Hv9P1R8/T8AAAAAAAAAAAEAAAAAAAAA
81pAPwAAAAAYuglAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAH4hyA==

[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
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================= CORE DUMP END =================
Rebooting...
ets Jun  8 2016 00:22:57

rst:0xc (SW_CPU_RESET),boot:0x17 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:1
load:0x3fff8028,len:8
load:0x3fff8030,len:1728
load:0x4009fa00,len:0
load:0x4009fa00,len:14592
entry 0x400a059c
-----------------------------------------------------------------------------
LOG   :: Loading XYZ
Guru Meditation Error: Core  0 panic'ed (InstrFetchProhibited)
. Exception was unhandled.
Register dump:
PC      : 0x00000000  PS      : 0x00060430  A0      : 0x8011a4c9  A1      : 0x3ffbd650  
A2      : 0x00000000  A3      : 0x00000037  A4      : 0xffffffa3  A5      : 0x3fbc1e28  
A6      : 0x00000008  A7      : 0x00000000  A8      : 0x801257a4  A9      : 0x3ffbd640  
A10     : 0x3fbc1e44  A11     : 0x00000037  A12     : 0xffffffa3  A13     : 0x3ffbd6e4  
A14     : 0x7777715b  A15     : 0x7777715b  SAR     : 0x00000010  EXCCAUSE: 0x00000014  
EXCVADDR: 0x00000000  LBEG    : 0x4009b2dd  LEND    : 0x4009b311  LCOUNT  : 0xffffffff  

Backtrace: 0x00000000:0x3ffbd650 0x4011a4c6:0x3ffbd670 0x4011b4d3:0x3ffbd740 0x40131a71:0x3ffbd760 0x401335d3:0x3ffbd7b0

================= CORE DUMP START =================
oDUAABAAAABsAQAA
WNj7P5DV+z9Q2Ps/
sNb7P/DX+z8p152hlFL8P5RS/D9Y2Ps/jFL8PwIAAADowfs/6MH7P1jY+z8AAAAA
FwAAAFTI+z93aWZpAPLMRVVZwuIcsYcAAAAAAFDY+z8AAAAAIAQGABcAAAABAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAACEe/0/7Hv9P1R8/T8AAAAAAAAAAAEAAAAAAAAA
81pAPwAAAAAYuglAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAH4hyA==

[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
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================= CORE DUMP END =================
Rebooting...
ets Jun  8 2016 00:22:57

rst:0xc (SW_CPU_RESET),boot:0x17 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:1
load:0x3fff8028,len:8
load:0x3fff8030,len:1728
load:0x4009fa00,len:0
load:0x4009fa00,len:14592
entry 0x400a059c
-----------------------------------------------------------------------------
LOG   :: Loading XYZ
Guru Meditation Error: Core  0 panic'ed (InstrFetchProhibited)
. Exception was unhandled.
Register dump:
PC      : 0x00000000  PS      : 0x00060030  A0      : 0x8011a4c9  A1      : 0x3ffbd650  
A2      : 0x00000000  A3      : 0x00000037  A4      : 0xffffffa2  A5      : 0x3fbc1e28  
A6      : 0x00000008  A7      : 0x00000000  A8      : 0x801257a4  A9      : 0x3ffbd640  
A10     : 0x3fbc1e44  A11     : 0x00000037  A12     : 0xffffffa2  A13     : 0x3ffbd6e4  
A14     : 0x7777715b  A15     : 0x7777715b  SAR     : 0x00000010  EXCCAUSE: 0x00000014  
EXCVADDR: 0x00000000  LBEG    : 0x4009b2dd  LEND    : 0x4009b311  LCOUNT  : 0xffffffff  

Backtrace: 0x00000000:0x3ffbd650 0x4011a4c6:0x3ffbd670 0x4011b4d3:0x3ffbd740 0x40131a71:0x3ffbd760 0x401335d3:0x3ffbd7b0

================= CORE DUMP START =================
sDUAABAAAABsAQAA
WNj7P5DV+z9Q2Ps/
oNX7P/DX+z8p152hlFL8P5RS/D9Y2Ps/jFL8PwIAAADowfs/6MH7P1jY+z8AAAAA
FwAAAFTI+z93aWZpAPLMRVVZwuIcsYcAAAAAAFDY+z8AAAAAIAAGABcAAAABAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAACEe/0/7Hv9P1R8/T8AAAAAAAAAAAEAAAAAAAAA
81pAPwAAAAAYuglAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAH4hyA==

[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]

ODQIQDS7CEAwBwYAs4sOgGD3/T9M2f0/APj9P5jZ/T8AAAAAoNn9PwAAAAA0uwiA
QPf9PwEAAAD/////uFL8PwEAAAAEGfw/AAAAAAAAAAAogfk/AAAAAAAAAAAAAAAA
AAAAADE2CEABAAAANNgIQCiB+T8AAAAAAAAAAAAAAAD//z+zAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAtAAAApaWlpaWlpaXk2A2AoPf9P7he/D8A+P0/
AAAAADYAAAClpaWlpaWlpf////+g9/0/lGH8PwD4/T8AAAAAAQAAAKxe/D88NPw/
AAAAADD4/T+sXvw/AAAAAFD4/T8AAAAAAAAAAAAAAAAAAAAArF78PwAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAwYPw/
MGD8PwAAAAAA+P0/ABQAACiB+T8AAAAAAAAAAAAAAAAwYPw/AAAAAAoAAAD///9/
AAAAAFD4/T8AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAABc+P0/AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAA==
================= CORE DUMP END =================
Rebooting...
ets Jun  8 2016 00:22:57

rst:0xc (SW_CPU_RESET),boot:0x17 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:1
load:0x3fff8028,len:8
load:0x3fff8030,len:1728
load:0x4009fa00,len:0
load:0x4009fa00,len:14592
entry 0x400a059c
-----------------------------------------------------------------------------
LOG   :: Loading XYZ
Guru Meditation Error: Core  0 panic'ed (InstrFetchProhibited)
. Exception was unhandled.
Register dump:
PC      : 0x00000000  PS      : 0x00060030  A0      : 0x8011a4c9  A1      : 0x3ffbd650  
A2      : 0x00000000  A3      : 0x00000037  A4      : 0xffffffa4  A5      : 0x3fbc1e28  
A6      : 0x00000008  A7      : 0x00000000  A8      : 0x801257a4  A9      : 0x3ffbd640  
A10     : 0x3fbc1e44  A11     : 0x00000037  A12     : 0xffffffa4  A13     : 0x3ffbd6e4  
A14     : 0x7777715b  A15     : 0x7777715b  SAR     : 0x00000010  EXCCAUSE: 0x00000014  
EXCVADDR: 0x00000000  LBEG    : 0x4009b2dd  LEND    : 0x4009b311  LCOUNT  : 0xffffffff  

Backtrace: 0x00000000:0x3ffbd650 0x4011a4c6:0x3ffbd670 0x4011b4d3:0x3ffbd740 0x40131a71:0x3ffbd760 0x401335d3:0x3ffbd7b0

================= CORE DUMP START =================
8DUAABAAAABsAQAA
WNj7P5DV+z9Q2Ps/
sNb7P/DX+z8p152hlFL8P5RS/D9Y2Ps/jFL8PwIAAADowfs/6MH7P1jY+z8AAAAA
FwAAAFTI+z93aWZpAPLMRVVZwuIcsYcAAAAAAFDY+z8AAAAAIAAGABcAAAABAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAACEe/0/7Hv9P1R8/T8AAAAAAAAAAAEAAAAAAAAA
81pAPwAAAAAYuglAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAH4hyA==

[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
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================= CORE DUMP END =================
Rebooting...
ets Jun  8 2016 00:22:57

rst:0xc (SW_CPU_RESET),boot:0x17 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:1
load:0x3fff8028,len:8
load:0x3fff8030,len:1728
load:0x4009fa00,len:0
load:0x4009fa00,len:14592
entry 0x400a059c
-----------------------------------------------------------------------------
LOG   :: Loading XYZ
Guru Meditation Error: Core  0 panic'ed (InstrFetchProhibited)
. Exception was unhandled.
Register dump:
PC      : 0x00000000  PS      : 0x00060430  A0      : 0x8011a4c9  A1      : 0x3ffbd6d0  
A2      : 0x00000000  A3      : 0x00000037  A4      : 0xffffffa4  A5      : 0x3fbc1e24  
A6      : 0x00000008  A7      : 0x00000000  A8      : 0x801257a4  A9      : 0x3ffbd6c0  
A10     : 0x3fbc1e40  A11     : 0x00000037  A12     : 0xffffffa4  A13     : 0x3ffbd764  
A14     : 0x7777715b  A15     : 0x7777715b  SAR     : 0x00000010  EXCCAUSE: 0x00000014  
EXCVADDR: 0x00000000  LBEG    : 0x4009b2dd  LEND    : 0x4009b311  LCOUNT  : 0xffffffff  

Backtrace: 0x00000000:0x3ffbd6d0 0x4011a4c6:0x3ffbd6f0 0x4011b4d3:0x3ffbd7c0 0x40131a71:0x3ffbd7e0 0x401335d3:0x3ffbd830

================= CORE DUMP START =================
6DUAABAAAABsAQAA
3Nj7PxDW+z/U2Ps/
MNf7P3DY+z8AAAAAlFL8P5RS/D/c2Ps/jFL8PwIAAABwUPw/cFD8P9zY+z8AAAAA
FwAAANjI+z93aWZpAAAAAAAAAAAAAAAAAAAAANTY+z8AAAAAIAQGABcAAAABAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAACEe/0/7Hv9P1R8/T8AAAAAAAAAAAEAAAAAAAAA
81pAPwAAAAAYuglAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAPcSQA==

[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
[CANNOT POST TO LONG MSGS HERE, SEE LOG_FILE FOR FULL LOG]
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================= CORE DUMP END =================
Rebooting...
ets Jun  8 2016 00:22:57

rst:0xc (SW_CPU_RESET),boot:0x17 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:1
load:0x3fff8028,len:8
load:0x3fff8030,len:1728
load:0x4009fa00,len:0
load:0x4009fa00,len:14592
entry 0x400a059c
-----------------------------------------------------------------------------
LOG   :: Loading XYZ
-----------------------------------------------------------------------------
DEBUG :: START-UP                                 :: @ 3  :: FREE MEM 2507104
-----------------------------------------------------------------------------
DEBUG :: ENABLE GC                                :: @ 3  :: FREE MEM 2506768
DEBUG :: IMPORT MACHINE                           :: @ 3  :: FREE MEM 2506432
-----------------------------------------------------------------------------
DEBUG :: IMPORT PyTrack                           :: @ 5  :: FREE MEM 2494080
DEBUG :: IMPORT WDT                               :: @ 5  :: FREE MEM 2493632
DEBUG :: @Getting a Watch Dog
DEBUG :: @Resting Watch Dog for 20 Sec
LOG   :: Define py()
-----------------------------------------------------------------------------
DEBUG :: @Resting Watch Dog for 30 Sec
DEBUG :: @Feeding Watch Dog
DEBUG :: IMPORT PyCom                             :: @ 5 :: FREE MEM 2491840
LOG   :: @pycom.heartbeat(False)
LOG   :: @pycom.rgbled(dBrown)
-----------------------------------------------------------------------------
LOG   :: Machine Reset Cause: 0 : POWERON_RESET
LOG   :: Machine Wake-Up Reason: 0 : PWRON_WAKE
LOG   :: Machine Wake-Up GPIO List: None
LOG   :: PyTrack/PySense Get Wake-up Reason: 2 : WAKE_REASON_PUSH_BUTTON
-----------------------------------------------------------------------------
CANNAT SHOW YOU MORE OF OUR LOGS FROM OUR CODE ... NDA ... BUT IT'S WORKING!
CANNAT SHOW YOU MORE OF OUR LOGS FROM OUR CODE ... NDA ... BUT IT'S WORKING!
CANNAT SHOW YOU MORE OF OUR LOGS FROM OUR CODE ... NDA ... BUT IT'S WORKING!
CANNAT SHOW YOU MORE OF OUR LOGS FROM OUR CODE ... NDA ... BUT IT'S WORKING!
CANNAT SHOW YOU MORE OF OUR LOGS FROM OUR CODE ... NDA ... BUT IT'S WORKING!
CANNAT SHOW YOU MORE OF OUR LOGS FROM OUR CODE ... NDA ... BUT IT'S WORKING!
CANNAT SHOW YOU MORE OF OUR LOGS FROM OUR CODE ... NDA ... BUT IT'S WORKING!
-----------------------------------------------------------------------------
LOG   :: Waiting for 5 seconds  OK
DEBUG :: @Feeding Watch Dog
DEBUG :: @RUN_GPS_LOC_COUNT: 5

---------- 2019-02-06 20:45:57 +0100: Disconnected ----------

COMMENT: IT'S ENDING AS IT SHOULD!

LOG_File:
2019-02-06 20-44-13 Pytrack_BAK.log

COMMENTS:

• @ 1st time boot ... it only panic's with "Guru Meditation Error" when we try to define

py = Pytrack()

• then in loops through a couple of "Guru Meditation Error" Panic's @ every reboot when we start loading our main.py from boot.py

machine.main('main_XYZ.py')

• Lastly, after a couple of Panic reboots ... it's does run the code ... flawlessly ... and enters Deep Sleep Mode ... (as it's programmed to do...)

• Then @ 1st boot after Deep Sleep Mode ... it does the same thing again ... Panic's @ define Py .... repeats it Panic's @ loading XYZ .... and then runs the code again ... and on and on it goes like this ...

• Yes, USB-Cable was attached ... funny thing is ... if I put the device (PyTrack+FiPy) on the palm rest of my Mac (left side) ... it started running the code without any Panic's ... But it back on the dashboard ... it started panicing again

• USB-Cable still attached ... put it inside an ESD-bag ... placed it on the dashboard ... and it was running as it should ... took it out ... all Panic's happened again ...

• We ran 3pcs of (PyTrack+FiPy) devices ... 2pcs "Freelance" ... 1 pcs Hitched with USB-cable ... we could see from the Color's blinking that the two "Freelance" where running ... though since we now know that the code is running perfectly after a few Panic reboots ... it's hard to say if they didn't just Panic reboot until it just ran the code (very quickly ...)

• But we did notice that at the moment we left the place ... all three devices (Freelance & Hitched) at the same instance just booted-up and began running.

• Futher more, we did have a Joker with us ... a PySense+FiPy device ... and guess what?!?!? :-) ... it ran perfectly all of the time ... with USB-Cable Attached & Detached ... and we could do everything it was programmed to do with it ...

• So we started thinking what's the difference ... and one of our thoughts was the GPS-module on the PyTrack ... and the following caught our eyes in one of the logs:

Traceback (most recent call last):
  File "main_XYZ.py", line 971, in <module>
  File "/flash/lib/L76GNSS_BAK.py", line 146, in coordinates
  File "/flash/lib/L76GNSS_BAK.py", line 90, in _read
OSError: I2C bus error
Pycom MicroPython 1.18.1.r7 [v1.8.6-849-d1c5ea9] on 2018-12-17; FiPy with ESP32
Type "help()" for more information.
>>>

• We have slightly modified our L76GNSS ... but it's only DEBUG-ing lines we added when we looked into improving GPS location ... ergo Line 90 equals Line 27 in the original L76GNSS ... and it states:

self.reg = self.i2c.readfrom(GPS_I2CADDR, 64)

• If you look at our tweaked pycoproc.py ... you'll see that we added some "WAIT_4_IT"-while-loops to read ... as one shouldn't take for grand that the device on the bus is always available ... it might sometimes be off ... so a "WAIT_4_IT"-while-loop add flexibility into the code ... especially when you want to run production code In-Real-Life :-) ... [It's a quick fix we'll implement ourselves until you add it to the official library]

• Further more, looking at the docs for Guru Meditation Errors from ESPRESIFF ... we find InstrFetchProhibited

InstrFetchProhibited
This CPU exception indicates that CPU could not load an instruction because the the address of the instruction did not belong to a valid region in instruction RAM or ROM.

Usually this means an attempt to call a function pointer, which does not point to valid code. PC (Program Counter) register can be used as an indicator: it will be zero or will contain garbage value (not 0x4xxxxxxx).

• So this Instruction is being loaded into RAM when using a PyTrack-board ... but never when using a PySense-board .... *hmm*

• and it is still there in the RAM ... until several reboots ... but then it disappears from RAM (or being replaced with something else?...) ... and somehow it then all works .... defining Py = PyTrack() ... and after a clean run of the code ... it goes through the same Panic-loop again ... *hmm*

• In regards to the EMF Detector we where running on the iPhone ... it workes ... but it only detects things best at close range ... the highest reading in that field (in the air) was ~ 90-110 uT ... we drove under the Power Line to and didn't get a higher reading ... but reading in close range .... like on certain places on my Mac I can max it out to above 2800 uT ... and 1 cm above it it drops ~1000-1500 uT .... 5 cm ~ 100-200 uT ... 10cm ~30 uT ... so a bit of mixed feelings if it's it a good enough EMF detector to use ... but it did read a higher then normal value at the place of ~90-110 uT ... compared to at home ~30 uT ...

NOTE: We have improved our code for: pycoproc.py
Since we noticed that we had a lot of issues with I2C Bus Error's

[combaindeft]

@martinnn said in Guru Meditation Error & Magnetic Interference (EMI/RFI):

@combaindeft
What does your physical setup look like? Cables, connections...?

• 3 pcs of PyTrack+FiPys .... 2pcs ran Freelance (on battery power) ... 1pcs ran on battery+usb-cable ...

• 1pcs of PySense+FiPys ... we running on battery power ... and we attached & detached the usb-cable from it .. on matter what we did to it ... it just ran ... ergo dubed The Joker

• USB-Cable(s)? .... we choose to use the best ones ... rated for Power & Data connection ... as some only do Power and never Data (or say, do Power, and extremely poorly Data over it ... guessing the ones that do both have better shielding inside of them)

I honestly doubt that any module alone could be affected by any kind of power line - power lines are 50 Hz mostly, field strength might be something but yours does not look like a 380 kV one. I would suspect that your setup contains some long wires as antenna or worse: loops that pick up some signal.

• And yeah, we're running a MacBook Pro ... Aluminium Case ... and one thought we have is that it might be the Aluminum Casing of the Mac that Act's as an Antenna or sorts ... and creates EMI in the USB-Cable that is attached to one of the devices ... But this doesn't quite answer the entire picture ... since we noticed when we drove away from the Power Line(s) that all 3pcs (two Freelance & one Hitched) ... all booted up at the same time ... *hummMmm*

• According to Wikipedia, SLF (Super low frequency),
  30 Hz to 300 Hz have been used by:

Radio amateurs have received signals in this range using simple receivers built around personal computers, with coil or loop antennas connected to the PCs sound card. Signals are analysed by a software fast Fourier transform algorithm and converted into audible sound.[3]

• Using the EMF Detector on my MacBook, it is at the speakers that I get the highest reading of ~2800-3000 uT

You write that you use the Pysense. I am also using a pysense/wipy combination

• Yes we are.(though with FiPy's...)

and I suspect these are extremely sensitive with a USB cable connected. In my office, I had six of those running on 4.2V (battery connector powered from lab power supply), which are still running (MQTT send every 2s via wifi). Five units are connected via USB (one to my laptop, four to a powered hub), of which three died in the past two days. Same pattern in the days before. I have standalone units running for two weeks now.

• Once in an office we had so much Electrostatic charged air air ... you couldn't touch any electronic boards without having a ground wire attached to yourself ... or you'd get a nice shock ...

• And yes, the usb-cable does make sense to look at .... but it doesn't explain why all PyTrack+FiPy devices (Freelance & Hitched) came back online at the exakt moment ... and began running their code ... if it was the usb-cable then the device hooked to it shouldn't have come back online (and the logs should have kept loging the Panic Core dump ... until x-reboots ... before it ran the code once well...)

So it seems you don't need a power line to make those things fail.

• Just some EMI to interfere with something on the board ... According to our Hardware guy ... it should be a software issue and not a Hardware-component issue.

• In our case we did get an explicit pointer that it must be some software/firmware issue ... as it states "Guru Meditation Error: Core 0 panic'ed (InstrFetchProhibited). Exception was unhandled." ... and that our code was running after x-reboots ... and then failed ... and ran again .... if it where a HW issue ... we shouldn't have been able to run any code ... also ... it does look that since we We have improved our code for: pycoproc.py the PySence+FiPy is working without any issue(s) ...

Guru Meditation Error: Core  0 panic'ed (InstrFetchProhibited)
. Exception was unhandled.
Register dump:
PC      : 0x00000000  PS      : 0x00060e30  A0      : 0x8011a4c9  A1      : 0x3ffbd650  
A2      : 0x00000000  A3      : 0x00000037  A4      : 0xffffffa4  A5      : 0x3fbc1e24  
A6      : 0x00000008  A7      : 0x00000000  A8      : 0x801257a4  A9      : 0x3ffbd640  
A10     : 0x3fbc1e40  A11     : 0x00000037  A12     : 0xffffffa4  A13     : 0x3ffbd6e4  
A14     : 0x7777715b  A15     : 0x7777715b  SAR     : 0x00000010  EXCCAUSE: 0x00000014  
EXCVADDR: 0x00000000  LBEG    : 0x4009b2dd  LEND    : 0x4009b311  LCOUNT  : 0xffffffff  

Backtrace: 0x00000000:0x3ffbd650 0x4011a4c6:0x3ffbd670 0x4011b4d3:0x3ffbd740 0x40131a71:0x3ffbd760 0x401335d3:0x3ffbd7b0

Can you try running the pysense boards without connections? Just add a battery and set them to communicate wirelessly?
@pycom: it seems you might have some work to do regarding the pysense

• From our test yesterday, The Joker (PySense+FiPy) devices worked without any issues ... and it was only with the PyTrack+FiPy that we all the issues with.

• Although, do note: We have improved our code for: pycoproc.py
  Since we noticed that we had a lot of issues with I2C Bus Error's

• @Martinnn - Maybe try it out yourself? and see if it solve your issue with the PySense+WiPy?

• Loosely & Planing of running more tests ... and in one of them I'll use the standard lib from PyCom GitHub ... vs our own improved one ... and seee.

• Also thinking of writing a specific test script ... where I'll cycle through all colours (Rolling-Rainbow...) ... and systematically one by one run one pice of our code-line ... and see how far it'll run through the code ... before it stats panicing.

[Paul Thornton]

@combaindeft Thanks for this. (and your email). I've shared the info with the team to see what they can come up with.

will update this thread with whatever they come back with asap.