Enabling additional features¶

The SCK has certain features that are disabled by default in order to save flash memory. However these features can be enabled with simple flags at compilation time.

The available features range from enabling additional supported sensors to other features like enabling the oled display.

Firmware version

This page refers to firmware V0.9.12 onwards. In previous versions, the flags were named WITH_* instead of SCK_WITH_*.

Process¶

To enable these features, you need to compile the firmware with the relevant compile flags. You can do this in two ways:

Add the flags to the environment you are compiling in the platformio.ini file, in the sam directory. For instance, to add the SPS30 to the sck23_air environment:

[env:sck23_air]
extends = env_air_common
build_flags =
    ${env_common.build_flags}
    !sh ../tools/git-rev.sh -e sck23_air
    -D SCK23_AIR
    -D SCK_WITH_SPS30

Alternatively, you can add a #define line inside the block of your configuration at the top of the Sensors.h file. For instance, for the SCK23_AIR configuration:
```
#ifdef SCK23_AIR
#define SCK_WITH_SEN5X
...
#define SCK_WITH_SPS30
#endif
```

Libraries

Each environment in platformio.ini only includes the libraries needed by the sensors it enables by default (under lib_deps). If you enable a sensor that is not enabled by default in your environment, make sure that its library is also available. For instance, the libraries for the SCD4X and the AS7341 are only listed in the sck23_air environment. If you want to use them with another configuration, copy them to the lib_deps of that environment.

Flash memory

The flash memory of the SCK is limited. Enabling many additional features at the same time might make the firmware too big to fit. If that happens, disable the features you don't need.

List of features¶

Different versions of the SCK have different features enabled by default. Additionally, the field of measurement (air or water) has different sensors enabled. These configurations are defined with the SCK21_AIR, SCK22_AIR, SCK23_AIR and SCK_WATER flags, each of them with its own environment in platformio.ini (sck21_air, sck22_air, sck23_air and sck_water). Since the _WATER sensors can be used with any data board (SCK2.1 onwards), they are independent of the hardware version.

The Sensors.h file defines which features are enabled for each configuration:

Flag	SCK21_AIR	SCK22_AIR	SCK23_AIR	SCK_WATER
`SCK_WITH_URBAN`	✓	✓	✓
`SCK_WITH_NOISE`	✓	✓	✓
`SCK_WITH_PMS`	✓
`SCK_WITH_CCS811`	✓
`SCK_WITH_SEN5X`		✓	✓
`SCK_WITH_MPL`	✓		✓
`SCK_WITH_LPS33`		✓
`SCK_WITH_AS7331`		✓	✓
`SCK_WITH_ADS1X15`	✓	✓	✓
`SCK_WITH_SCD30`	✓	✓	✓
`SCK_WITH_SFA30`	✓	✓	✓
`SCK_WITH_EXT_TEMP`	✓	✓	✓
`SCK_WITH_SCD4X`			✓
`SCK_WITH_AS7341`			✓
`SCK_WITH_GPS`	✓	✓	✓	✓
`SCK_WITH_ATLAS`				✓

Sensor flags¶

Features starting with SCK_WITH_ involve sensors or additional boards. Besides the ones in the table above, the following flags are available, but not enabled in any of the default configurations:

#define SCK_WITH_SPS30          // Sensirion SPS30 PM sensor
#define SCK_WITH_BME68X         // Bosch BME680 environmental sensor
#define SCK_WITH_GASES_BOARD    // SCK Gases Board for Alphasense sensors
#define SCK_WITH_GROVE_I2C_ADC  // Seeed Grove I2C ADC
#define SCK_WITH_INA219         // TI INA219 current sensor
#define SCK_WITH_DS18B20        // DS18B20 temperature sensor (via DS2482 I2C bridge)
#define SCK_WITH_DALLAS_TEMP    // Dallas temperature sensor directly on the AUX connector
#define SCK_WITH_CHIRP          // Catnip Chirp soil moisture sensor
#define SCK_WITH_RANGE          // VL6180x range sensor

A complete list is available in Sensors.h.

Oled display¶

The oled display is enabled with the SCK_WITH_SENSOR_GROVE_OLED flag. Since it is a common option, platformio.ini already includes an environment with it for each configuration: sck21_air_oled, sck22_air_oled, sck23_air_oled and sck_water_oled.

Additional features¶

Default temperature calibration parameters (in the form of an offset) are defined for each configuration with the following:

#define URBAN_T_OFFSET -1.0
#define URBAN_RH_OFFSET 3.5

Better use the shell

The calibration parameters can be changed directly using the shell, without recompiling the firmware.