Platformio XIAO ESP32S3 Modbus Slave Exploration

This exploration project is to test the integration of esp-modbus in server(slave) configuration on the XIAO ESP32S3 connected on WIFI using the ESP-IDF example connection configuration. It forwards the data of a BME688 ambient sensor to three input registers starting at address 1. It also has a writable holding register at address 1 that sets the ambient sense measurement period (default 1000ms). Run ESP-IDF menuconfig to set WIFI SSID and password for the ESP32 to connect to your LAN before compiling and running.

You can see the sense data read with a modbus master software, as QModMaster.

You can see the sense period write:

Seeed Xiao ESP32-S3 references:

https://docs.platformio.org/en/latest//boards/espressif32/seeed_xiao_esp32s3.html https://wiki.seeedstudio.com/xiao_esp32s3_getting_started/

Debug on Windows:

References https://community.platformio.org/t/how-to-use-jtag-built-in-debugger-of-the-esp32-s3-in-platformio/36042 and https://mydicedevice.com/?p=514.

1. Install latest version of "Espressif - WinUSB support for JTAG (ESP32-C3/S3)" driver https://docs.espressif.com/projects/esp-idf/en/latest/esp32s3/api-guides/jtag-debugging/configure-builtin-jtag.html.
2. Download Zadig https://zadig.akeo.ie/.
3. In Zadig, list all devices under options.
4. Install USB CDC driver for USB JTAG/serial debug unit (interface 0).
5. Install libusbK driver for USB JTAG/serial debug unit (interface 2).
6. Use platformio.ini from this project and update COM ports.
7. Upload and debug should now work through esp-builtin interface!

Espressif Modbus TCP Example:

https://github.com/espressif/esp-idf/tree/master/examples/protocols/modbus/tcp