Make ESP8266 not restart on crash?

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1

Hello all, is there any way to make an ESP8266 (specifically a NodeMCU) not restart in the case of a crash? I mean this kind of crash:

--------------- CUT HERE FOR EXCEPTION DECODER ---------------

Exception (28):
epc1=0x4000bdc8 epc2=0x00000000 epc3=0x00000000 excvaddr=0x00000000 depc=0x00000000

>>>stack>>>

ctx: cont
sp: 3ffffd60 end: 3fffffd0 offset: 0150
3ffffeb0:  3fff9fec 3fff9fec 3fff3560 3ffe88c9  
...

I've of course done everything I could've to prevent them in my program, but even just the obscure reasons I've had them happen to me for are enough to convince me I won't be able to 100% crashproof my program. Maybe a random null in a JSON response when the server used to send a string in that place for a whole year before that, and my ESP is crashing and restarting and crashing...
Now that crashing and restarting wouldn't be a problem if I wasn't sending http requests on every startup. But I am, and if the ESP keeps crashing and sending new ones that could be enough to get me banned from the API I am reading from.
Is there any way to make the ESP maybe just not restart on crash and wait until the RST button is pressed? Or some other way to tackle this problem? Thanks in advance.

2

I suggest trying to identfy what causes the "crash". The word "crash" doesn't tell much.
Personally schematics are interesting as powering mistakes can't be excluded at this point. Code might also tell more.

3

Well you haven't done everything since you are still getting exceptions. Exception 28 is an invalid pointer, and since excvaddr=0x00000000 it is probably a NULL pointer.

Use the ESP exception decoder to figure out where the exception is happening and fix the code. If you are doing operations where there may be a NULL pointer check it before using. If you are dynamically allocating storage check that the pointer is valid before you use it. If you are passed a pointer that may be NULL (like null elements in a structure) check it before use.

4

There's no crash right now, I want to leave my thing esp for months at a time, this is in case it crashes during the time it's running due to some variable I haven't accounted for. I want it to not restart if it were to crash. I don't want it to send a million requests before I get to see something went wrong.

5

Sorry, I guess I wasn't clear enough in my post, that was just an illustrative example of the kind of crash I am talking about, to make clear it's the kind of crash that restarts the esp. There's no crash right now, I just wanna make sure it won't restart in case there would be a crash in the future.

6

You got a really good tip in #3.
Still, posting the code might bring up more ideas among other helpers. As already told, bad pointers will create just any kind of trouble.
Plugging possible bug holes is defenatly worth going for.

7

My memory is that the ESP processors have a code that tells you why it rebooted.

8

It is 28.

9

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