This is a project for a DIN rail Modbus Data Logger. The idea was to record the energy production of a photo voltaic installation using a data logger that also works offline. The data logger will read values off the energy counter at regular intervals. The values are then stored with a time stamp on the SD card. The log files can later be retrieved via a WiFi access point. The status of this project is currently: prototype/proof of concept.
This software is build using PlatformIO Core. Once you have installed the PIO binaries you can execute pio run to build the firmware and pio run -t upload to flash the firmware onto the ESP32 S3. To upload the web interface to SPIFFS execute pio run -t uploadfs. Please also take a look at platformio.ini for the additional libraries this project depends upon. On Linux/macOS feel free to use the Makefile wrapper to start the build.