The following steps allow you to setup the Arduino IDE such that you can compile, modify and upload the code yourself.

Preparation

Arduino IDE

Get the latest Arduino IDE software from arduino.cc/en/Main/Software

ESP32 support

File -> Preferences (or Arduino -> Preferences on MacOS)

go to "Additional Board Manager URLs"

Add https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json and press OK

Tool -> Board -> Boards Manager

search for "esp32"

Install "esp32 by Espressif Systems"

You need version 1.0.6. Version 2.0.0 is not yet supported

ESP32 Flash Filesystem Upload support

Get the zip file of the latest release from https://github.com/me-no-dev/arduino-esp32fs-plugin/releases/

Unzip the content to the tools folder of your Arduino IDE (~/Documents/Arduino/tools on MacOS – if this folder does not exist, you have to create it, see the README on the plugin git main page; similar on other OS) and restart IDE

Install all required components

Additional libraries

Select Tools -> Library Manager

Install "U8g2"

Install "MicroNMEA"

Install "GFX Library for Arduino"

Additional libraries, part 2

From https://github.com/me-no-dev/ESPAsyncWebServer select "Download ZIP", extract to the libraries folder of your Arduino IDE (~/Documents/Arduino/libraries on MacOS), rename main folder to ESPAsyncWebServer (remove the "-master")

From https://github.com/me-no-dev/AsyncTCP select "Download ZIP", extract to the libraries folder of your Arduino IDE, and rename main folder to AsyncTCP

Download https://github.com/lewisxhe/AXP202X_Library/archive/refs/tags/V1.1.3.zip and extract to the libraries folder of your Arduino IDE

NEW:

• Download https://github.com/dx168b/async-mqtt-client/archive/master.zip
• Load the .zip file with Sketch → Include Library → Add .ZIP Library

NO LONGER NEEDED: Additional libraries, part 3

For versions older than devel20210912 only:

Copy the libraries/SondeLib folder of this project to your Arduino IDE's libraries folders, or, alternatively, create symbolic links (MacOS/Linux):

cd ~/Documents/Arduino/libraries
ln -s <whereyouclonedthegit>/rdz_ttgo_sonde/libraries/SondeLib/ .

Restart the Arduino IDE

(symbolic links are the preferred way, otherwise you have to copy the the libraries again after each update)

Final steps

In the IDE Tools -> Board: -> Select "TTGO LoRa32-OLED v1" (or T-Beam, or something that fits your needs)

Compile and Upload code

Upload data to SPIFFS with Tools -> ESP32 Sketch Data Upload