Examples

Complete ESP32-S3 applications that read an SFM4300 with the driver, from a one-frame-per-second minimum to a 500 Hz loop with statistics.

They run on an ESP32-S3 with the sensor on I2C0 (SDA GPIO 8, SCL GPIO 9, 400 kHz, address 0x2A); the port is hf_sfm_esp_i2c.hpp. CI builds every app below on each pull request.

The apps

App	What it shows	Source	CI
sfm_minimal_example	Soft reset, product identifier, air table, one flow / temperature / status frame per second	sfm_minimal_example.cpp	yes
sfm_flow_demo	500 Hz poll with fixed-N averaging, CO2 table when the variant has it, else air; 1 s statistics	sfm_flow_demo.cpp	yes

Build and flash one (from examples/esp32, ESP-IDF environment loaded):

./scripts/build_app.sh sfm_minimal_example Release
./scripts/flash_app.sh flash_monitor sfm_minimal_example Release

Source of this table: examples/esp32/app_config.yml.

Set up once

git submodule update --init examples/esp32/scripts   # the HardFOC ESP-IDF build scripts
cd examples/esp32
. $IDF_PATH/export.sh                                 # ESP-IDF v5.5
./scripts/build_app.sh list                           # every app and build type

The scripts read app_config.yml (the same file this page's table comes from) and build each app as its own firmware image.

What to read in an example

You want to	Read
See the smallest complete program: install the bus, reset, identify, start, read	sfm_minimal_example.cpp
Pick a gas from the variant and fall back to air	sfm_flow_demo.cpp, gas selection
Run a fixed-rate loop and count NoData and Crc results	sfm_flow_demo.cpp, the 500 Hz loop
Write an ESP-IDF port	include/hf_sfm_esp_i2c.hpp

The example folder's README has the wiring and the build commands.