Slow serial baudrates cause exceptions / WDT

Basic Infos

  • This issue complies with the issue POLICY doc.
  • I have read the documentation at readthedocs and the issue is not addressed there.
  • I have tested that the issue is present in current master branch (aka latest git).
  • I have searched the issue tracker for a similar issue.
  • If there is a stack dump, I have decoded it.
  • I have filled out all fields below.

Platform

  • Hardware: [ESP-12]
  • Core Version: [framework-arduinoespressif8266 2.7.4]
  • Development Env: [Platformio]
  • Operating System: [Windows]

Settings in IDE

  • Module: [WeMos D1 R2 and mini]
  • Flash Mode: [dio]
  • Flash Size: [4MB]
  • lwip Variant: [v1.4|v2 Lower Memory|Higher Bandwidth]
  • Reset Method: [clk]
  • Flash Frequency: [40Mhz]
  • CPU Frequency: [80Mhz]
  • Upload Using: [SERIAL]
  • Upload Speed: [115200] (serial upload only)
  • PlatformIO - ini file:
[env:d1_mini]
platform = espressif8266
board = d1_mini
framework = arduino
board_build.filesystem = littlefs

; COM1 or COM3
upload_port = COM[4]
upload_speed = 115200

monitor_port = COM[4]
monitor_speed = 115200
monitor_flags=
    --parity
    N

Problem Description

I want to use LittleFS to save some data coming from serial port at baudrate 110, N81
I tested the provided example in:
https://github.com/esp8266/Arduino/tree/master/libraries/LittleFS/examples/LittleFS_Timestamp
and it works fine at baudrate 115200
but when changing baudrate to 110, the code seems to retart (exception)

I need to have a running FS at baudrate of 110, because I can not change the baudrate of the device I am connected to.

Sketch

https://github.com/esp8266/Arduino/blob/master/libraries/LittleFS/examples/LittleFS_Timestamp/LittleFS_Timestamp.ino

Debug Messages

@ Baudrate 110
FS with 110 baudrate

@baudrate 115200
FS with 115200 baudrate