System Calls


System.enableFeature, enableFeature

int enableFeature(HAL_Feature feature)


Enables a system feature. System feature that are read/write or write only are persistent and saved to configuration flash.

Feature Read/Write Description
FEATURE_RETAINED_MEMORY Write Only Preserve retained memory on backup power
FEATURE_WARM_START Read Only True if previous retained memory contents were available
FEATURE_CLOUD_UDP Read Only True if cloud connection is UDP and the alt keys in the DCT are used
FEATURE_RESET_INFO Read/Write Store last reset reason in retained memory
FEATURE_WIFI_POWERSAVE_CLOCK Write Only Enable Wi-Fi Powersave clock on TESTMODE/P1S6 pin on P1. Disabling it allows P1S6 to be used as GPIO.
FEATURE_ETHERNET_DETECTION Read/Write Enable detection of Ethernet FeatherWing at boot
FEATURE_LED_OVERRIDDEN Read/Write Override RGB LED signaling at boot
FEATURE_DISABLE_EXTERNAL_LOW_SPEED_CLOCK Read/Write If true, use internal low-speed clock instead of the external crystal clock
FEATURE_DISABLE_LISTENING_MODE Read/Write Disable listening mode
  • Use System.disableFeature() to disable a feature flag after enabling it (for read/write or write only flags)
  • Use System.featureEnabled() to get the current value of the feature flag (for read/write or read only flags)
  • Beware of features such as FEATURE_DISABLE_LISTENING_MODE. Enabling the feature disables listening mode, and disabling the feature enables listening mode