Arduino IDE vs PlatformIO

Hello Everyone,

I’ve a problem with a sketch/program that i code for esp8266.

With the absolutly same source code, the result is not the same, under each dev environnement :

Compilation platformIO ( * Core 5.0.1·* Home 3.3.0 and uptodate libraries) :

RAM: [==== ] 44.5% (used 36488 bytes from 81920 bytes)
Flash: [==== ] 35.4% (used 369528 bytes from 1044464 bytes)

with long upload and the webServer on the esp dont work correctly (failed to send all files from Little FS).

Compilation Arduino IDE 1.8.3 and uptodate libraries:

The sktch use 383196 bytes (36%) of Flash space. Max is 1044464 bytes.
Globales variables use 35792 bytes (43%) of RAM, max is 81920 bytes.

Speedy upload and full functionnal.

Got you the same symptomes ?


Are you using the same upload speed as you’ve set in the Arduino IDE via the upload_speed directive, probably 921600?

Meaning what exactly? Any error message? You did upload the filesystem to the ESP8266 using the “Upload filesystem” project task?

To do a fair comparison you have to show what version of the ESP8266 board package you have installed in your Arduino IDE, not the Arduino IDE version.

Hi Maxgerherdt,
Thanks for your answer.
My english is not very good… :wink: But :slight_smile:
For the speed its the same on both environement 115200 for all communication.
For the file form LittleFS : i use the littleFS for my webserver’s files (html, js, css…).with the version compiled under PIO each file is served with 1 second (or more) delay and the browser (chrome or other) dont received all files and invoque timeout. But under arduino ide they are served immediatly. This is my real “bug”.
For the version of esp8266 core under arduino IDE it’s the 2.7.4. and under PIO this is framework-arduinoespressif8266 3.20704.0 (2.7.4) so 2.7.4 also ?

Thanks for your help



Do you have the project files for reproduction? What exact board settings are you using in the Arduino IDE?

Yes, those are equal.

Unfortunately, I can’t give to you my project. It’s a professionnal I don’t have the right. I only can say that i use for this project :

  • Wemos D1 mini R2 aka now lolinD1 mini v3.1.0
    with LittleFS for webser files and data (micro databases)
    IR receiver
    I2C componants


AP or STA wifi mode
UDP uni and multicast

But i’ll try to make a code that i can share for you.



It doesn’t have to be the exact code. The most minimal code which reproduces the problem is enough. E.g., do you observe differences in the example sketch Arduino/libraries/ESP8266WebServer/examples/FSBrowser at master · esp8266/Arduino · GitHub for Arduino IDE and PIO?

Yes i’ try that tomorrow.
Good night.

hi Maxgerhardt,
I’ve try the fsbrowser code this morning, And I’ve no symptome, no bug. I don’t have the time at this moment to do others tests, but i’ll make them in next days.
I’ll informe you about results.