OTA fails with watchdog timer reset after serial upload

[jackjansen]

Basic Infos

Hardware

Hardware: ESP-12E
Core Version: 2.3.0

Description

OTA from the Arduino IDE often fails for me (some days 80% of the time). If I have the serial port connected (just for debug output, not for uploading) what I see is that the watchdog timer triggers, the 8266 resets, and then goes off to never-never land. Power cycling is required to get it working again.

I'm using ArduinoOTA, not the http server. I've added wdtFeed() calls to the start/progress/end callbacks, which has helped a bit, but I'm still getting the resets fairly often. It may happen more of the WiFi is busy.

Could it be that there's a wdtFeed() or similar call missing in the ArduinoOTA inner loop?

Settings in IDE

Module: NodeMCU 1.0 (ESP-12E)
Flash Size: 4MB
CPU Frequency: 80Mhz
Upload Using: OTA

[penfold42]

Have you been resetting the ESP after a serial upload ?

This is required before using OTA to update it or else it will crash.

[jackjansen]

Hmm, I don't know... Whether or not I did a reset may be the difference between sometimes failing, sometimes not. I will experiment and report back here.

[penfold42]

Yup - it was driving me nuts until I stumbled across it in another issue

[namirda]

Hi Jack - you never came back to say if you had solved your problem. I would very much like to know.

I have exactly the same issue - ArduinoOTA fails most of the time with a wdt reset.

I dug into the ArduinoOTA library a little and found that the reset was occurring in the call to WiFiUDP::stopAll() in method ArduinoOTAClass::_runUpdate().

Adding a yield() before the call to WiFiUDP::stopAll() did not help and so I simply removed the call - I do not have any instances of WiFiUDP in my sketch. All my problems are now gone and OTA appears to work perfectly!

Maybe this helps you.

[jackjansen]

Sorry for not reporting back! The comment by @penfold42 hit the nail on the head: if you have uploaded via serial you must issue a reset before attempting an OTA upload. So I just made that reset part of my workflow while debugging my OTA code. I've changed the title of this bug report to reflect the findings.

It would be nice if this was documented somewhere (if not fixed).

[penfold42]

IIRC it can't be fixed

Maybe a reminder from the ESP upload tool would be nice

[devyte]

After a serial upload, the ESP must be manually reset before an OTA can work (actually, I think before a software reset as well). And I also think it can't be fixed.
Closing.