choice RTC_CLK_SRC prompt "RTC clock source" # TODO: IDF-9197 default RTC_CLK_SRC_INT_RC if IDF_TARGET_ESP32C5_MP_VERSION default RTC_CLK_SRC_INT_RC32K if IDF_TARGET_ESP32C5_BETA3_VERSION help Choose which clock is used as RTC clock source. config RTC_CLK_SRC_INT_RC depends on IDF_TARGET_ESP32C5_MP_VERSION bool "Internal 136kHz RC oscillator" config RTC_CLK_SRC_EXT_CRYS bool "External 32kHz crystal" select ESP_SYSTEM_RTC_EXT_XTAL config RTC_CLK_SRC_EXT_OSC bool "External 32kHz oscillator at 32K_XP pin" select ESP_SYSTEM_RTC_EXT_OSC config RTC_CLK_SRC_INT_RC32K bool "Internal 32kHz RC oscillator" endchoice config RTC_CLK_CAL_CYCLES int "Number of cycles for RTC_SLOW_CLK calibration" default 3000 if RTC_CLK_SRC_EXT_CRYS || RTC_CLK_SRC_EXT_OSC || RTC_CLK_SRC_INT_RC32K default 1024 if RTC_CLK_SRC_INT_RC range 0 8190 if RTC_CLK_SRC_EXT_CRYS || RTC_CLK_SRC_EXT_OSC || RTC_CLK_SRC_INT_RC32K range 0 32766 if RTC_CLK_SRC_INT_RC help When the startup code initializes RTC_SLOW_CLK, it can perform calibration by comparing the RTC_SLOW_CLK frequency with main XTAL frequency. This option sets the number of RTC_SLOW_CLK cycles measured by the calibration routine. Higher numbers increase calibration precision, which may be important for applications which spend a lot of time in deep sleep. Lower numbers reduce startup time. When this option is set to 0, clock calibration will not be performed at startup, and approximate clock frequencies will be assumed: - 136000 Hz if internal RC oscillator is used as clock source. For this use value 1024. - 32768 Hz if the 32k crystal oscillator is used. For this use value 3000 or more. In case more value will help improve the definition of the launch of the crystal. If the crystal could not start, it will be switched to internal RC.