The R-IoT v3 is ESP32-S3 based and compiles witht the ESPRESSIF arduino toolchain, currently v3.1.1 To compile with the Arduino IDE, ensure the following toolchain repository is added to the Arduino IDE preferences : https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json

ESP32-S3 dev module - USB Mode : USB-OTG / CDC on boot : enabled / DFU on boot : disabled Upload Mode : USB-OTG(TinyUSB) - CPU frequency : 160 MHz (or 80 MHz) / Flash Mode : QIO 80 MHz Flash Size : 8 MB / Partition : 8MB with FAT (2MB app / 3.7MB FFAT) - PSRAM : disabled

The default 3.1.1 toolchain must be updated with an additional partition table to use the 8MB flash size along with a 3.7 MB FATFS exposed over USB and combined with OTA updates File /tools/partitions/default_8MB.csv must be modified with the provided partition file that extends the FAT partition to 3.7MB.

To be able to use the 8MB-FATFS partition in the IDE, a new item must be added in the boards.txt definition (until we make a pull request on ESPRESSIF repo) Search for : esp32s3.name=ESP32S3 Dev Module

then in the partition scheme menu definition, add: esp32s3.menu.PartitionScheme.8MB_ota_ffat=8M with OTA and FATFS (2MB APP/3.7MB FATFS) esp32s3.menu.PartitionScheme.8MB_ota_ffat.build.partitions=default_ffat_8MB esp32s3.menu.PartitionScheme.8MB_ota_ffat.upload.maximum_size=2097152

The firmware uses several libraries that have to be separately installed either manually or using the Arduino library manager. We tried to limit those by using either local versions of the libraries or custom code & implementation like the low-level drivers of the IMU sensors.

Connect the R-IoT module to computer by USB It should mount a USB flashdrive of 3.7 MB. Format (FAT) if necessary Copy all data from the src/data folder in the root dir of the flashdrive Edit config.txt to your liking. Mandatory settings are the WiFi SSID (network name) and password to connect to