Module clock

CPU Clock Control

Overview

Clocks are mainly sourced from oscillator (OSC), RC, and PLL circuits, and then processed by the dividers or selectors, which allows most functional modules to select their working clock according to their power consumption and performance requirements.

The clock subsystem is used to source and distribute system/module clocks from a range of root clocks. The clock tree driver maintains the basic functionality of the system clock and the intricate relationship among module clocks.

Configuration

During HAL initialization, specify a CPU clock speed to configure the desired clock frequencies.

The CPU clock is responsible for defining the speed at which the central processing unit (CPU) operates. This driver provides predefined options for different CPU clock speeds, such as

• 80MHz
• 160MHz

Frozen Clock Frequencies

Once the clock configuration is applied, the clock frequencies become frozen and cannot be changed.

Examples

Initialize With Different Clock Frequencies

use esp_hal::clock::CpuClock;

// Initialize with the highest possible frequency for this chip
let config = esp_hal::Config::default().with_cpu_clock(CpuClock::max());
let peripherals = esp_hal::init(config);

Structs

PhyClockGuardunstable

Prevents the PHY clock from being disabled.

Enums

CpuClock

CPU clock speed

XtalClockunstable

XTAL clock speed

Traits

ModemClockControllerunstable

This trait provides common functionality for all

Functions

init_radio_clocksunstable

Do any common initial initialization needed for the radio clocks