PlatformIO + ESP32 + Ethernet + OTA Demo

Prerequisites

Must have

• an ESP32 dev board
• a W5500 Ethernet shield or module
  
  Those must be connected via the SPI bus (see default SPI connections)
  for upoloading via this method, the system must have curl installed

for Windows, install via https://curl.haxx.se/windows/ and put it into your system's PATH variable so that you can call it from anywhere inside your cmd.exe. Reboot your system if necessary.

Initial Sketch Upload

Use the given esp32dev environment to first transport the initial OTA code to the ESP32 module.

This is already the default environment in the platformio.ini (default_envs = ...).

Make sure the W5500 module is recognized and prints its DHCP address. Expected output:

Initialize Ethernet with DHCP:
 DHCP assigned IP 192.168.1.237
Link status: ON

If an error occurs, make sure you have

sufficiently good 3.3V power
all connections are sturdy and not loose
RESET of the W5500 module is connected to 3V3
Ethernet cable is connected

Also note down the IP address of the module.

Note that in the sketch, we initialize the authorization parmaters

 ArduinoOTA.begin(Ethernet.localIP(), "Arduino", "password", InternalStorage);

With a username Arduino and password password.

OTA upload

To upload via OTA, review the upload parameters inside the platformio.ini. Inside the upload_flags parameter, make sure to adapt the username, password, IP address and port (if changed).

Then use the upload method of the esp32dev_ota environment. Either select the environment via the platformio.ini by changing the default_env, press the Upload button in the environment that VSCode shows or use the commandline to select the environment, e.g. via

pio run -e esp32dev_ota -t upload -v

This should invoke your system's CURL to push the sketch to the ESP

CURRENT: upload_protocol = custom
curl --request POST --data-binary @"C:\Users\Maxi\Desktop\esp32_eth_ota\.pio\build\esp32dev_ota\firmware.bin" http://arduino:password@192.168.1.237:65280/sketch
 % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                Dload  Upload   Total   Spent    Left  Speed

 0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
 0  302k    0     0    0     0      0      0 --:--:--  0:00:01 --:--:--     0
26  302k    0     0   26 81920      0  81920  0:00:03  0:00:01  0:00:02 57007
52  302k    0     0   52  160k      0  81920  0:00:03  0:00:02  0:00:01 62060
74  302k    0     0   74  224k      0  76458  0:00:04  0:00:03  0:00:01 67344
95  302k    0     0   95  288k      0  73728  0:00:04  0:00:04 --:--:-- 66707
100  302k    0     0  100  302k      0  61875  0:00:05  0:00:05 --:--:-- 62664
100  302k    0     0  100  302k      0  51562  0:00:06  0:00:06 --:--:-- 45067
100  302k    0     0  100  302k      0  51562  0:00:06  0:00:06 --:--:-- 37860
=============================== [SUCCESS] Took 15.30 seconds ===============

Environment    Status    Duration
-------------  --------  ------------
esp32dev       IGNORED
esp32dev_ota   SUCCESS   00:00:15.296
==== 1 succeeded in 00:00:15.296 ====================

And thus we have a successful OTA upload.

Upload SPIFFS?

Arduino OTA has the possibility of uploading the SPIFFS via the /spiffs URL. This is not implemented in the PlatformIO integration, it only does sketch data. Feel free to expand.