Esp8266 crashes, anyway to trace cause without serial

[dr pepper]

A project I put together keeps crashing, its attached to a machine that has some large water pumps, if the pumps are off the esp works Ok, if the pumps are on after an hour or so it crashes and does not reboot, the board has a pullup on pin 0, or its sposed to have, might meter it.
Looks like noise is causing this, I'd like to find out what the error message is from esp, but I cannot leave my laptop connected to it, is there another way to log the messages.

 

[Pommie]

I had a similar problem a while ago. Added a 4G SD card and logged everything until I found where the problem was. Kinda started xxxx, finished xxx etc. The lack of debug facilities on the Arduino IDE is really backward.

Mike.

 

[Nigel Goodwin]

You can get tiny 'Arduino' based serial loggers, intended for use on Drones, basically a Drone version of an aircraft Black Box. They are absolutely tiny, just big enough for a micro-SD card, and log everything from a serial port to the card.

Easily available from China, however, be aware that they sometimes come unprogrammed, and there's no connections to program them, and their small size makes it VERY difficult to stick some connections on to program it. I ordered a couple to play with, and they came unprogrammed - I gave up

 

[dr pepper]

Yep just found them on the 'bay, 6 quid.
But I'll not bother if they are no good.
I have a esp32 cam module, it has an Sd might use that, in fact I could remotely check that online easily enough.

 

[Nigel Goodwin]

Yep just found them on the 'bay, 6 quid.
But I'll not bother if they are no good.

They are fine as long as they are programmed, so worth a try, and you can claim your money back if they aren't programmed.

 

[dr pepper]

I found something interesting, and got the thing to work much better.
Power to the Esp module comes from a 240vac to 5v smps module in a screened case, then that goes through about 6" of stout 24/0.2mm cable.
But its obviously not good enough, I soldered a 2200u cap directly across the 5v in on the Esp module.
The module now connects much better, data download is a lot quicker, and the readings when the page loads are either spot on or slightly high, about 10%.
So these things are very power supply sensitive, and it appears that they dont so much crash or not work with bad power, rather performance is degraded, I wasnt expecting that, thinking it would just work or not work.

 

[gophert]

I found something interesting, and got the thing to work much better.
Power to the Esp module comes from a 240vac to 5v smps module in a screened case, then that goes through about 6" of stout 24/0.2mm cable.
But its obviously not good enough, I soldered a 2200u cap directly across the 5v in on the Esp module.
The module now connects much better, data download is a lot quicker, and the readings when the page loads are either spot on or slightly high, about 10%.
So these things are very power supply sensitive, and it appears that they dont so much crash or not work with bad power, rather performance is degraded, I wasnt expecting that, thinking it would just work or not work.

The ESP modules are very power sensitive. Some big caps stabilize the onboard ADC that tend to jump around like crazy. Without, you end up with 8-bit resolution with the 12-bit ADC. I don't know who designed these modules but, more hours have been wasted by the DIY community trying to get them to work as advertised than the hours that went into designing the modules.

 

[dr pepper]

Yep your probably right.
The adc works well actually on this project, even before the big cap.
I've had issues with pic's before & found out on the 'F88 they only guarantee bit 0 accuracy when a a to d conversion is done with the chip in sleep.

I guess whats happening is the chip is sending packets to the router, and due to noisy power a lot of those are being corrupted, and the chips faffing about resending them, and that in turn might well be causing it to crash & lock up.

I just checked the system again from home & its fine, if no new pages are open for a while the first json's dont get corrupted because the system is able to process the request without missing interrupt ticks.