Module rp2040_hal::clocks

Expand description

Clocks (CLOCKS)

Usage simple

use rp2040_hal::{clocks::init_clocks_and_plls, watchdog::Watchdog, pac};

let mut peripherals = pac::Peripherals::take().unwrap();
let mut watchdog = Watchdog::new(peripherals.WATCHDOG);
const XOSC_CRYSTAL_FREQ: u32 = 12_000_000; // Typically found in BSP crates
let mut clocks = init_clocks_and_plls(XOSC_CRYSTAL_FREQ, peripherals.XOSC, peripherals.CLOCKS, peripherals.PLL_SYS, peripherals.PLL_USB, &mut peripherals.RESETS, &mut watchdog).ok().unwrap();

Usage extended

use fugit::RateExtU32;
use rp2040_hal::{clocks::{Clock, ClocksManager, ClockSource, InitError}, gpio::Pins, pac, pll::{common_configs::{PLL_SYS_125MHZ, PLL_USB_48MHZ}, setup_pll_blocking}, Sio, watchdog::Watchdog, xosc::setup_xosc_blocking};

let mut peripherals = pac::Peripherals::take().unwrap();
let mut watchdog = Watchdog::new(peripherals.WATCHDOG);
const XOSC_CRYSTAL_FREQ: u32 = 12_000_000; // Typically found in BSP crates

// Enable the xosc
let xosc = setup_xosc_blocking(peripherals.XOSC, XOSC_CRYSTAL_FREQ.Hz()).map_err(InitError::XoscErr)?;

// Start tick in watchdog
watchdog.enable_tick_generation((XOSC_CRYSTAL_FREQ / 1_000_000) as u8);

let mut clocks = ClocksManager::new(peripherals.CLOCKS);

// Configure PLLs
//                   REF     FBDIV VCO            POSTDIV
// PLL SYS: 12 / 1 = 12MHz * 125 = 1500MHZ / 6 / 2 = 125MHz
// PLL USB: 12 / 1 = 12MHz * 40  = 480 MHz / 5 / 2 =  48MHz
let pll_sys = setup_pll_blocking(peripherals.PLL_SYS, xosc.operating_frequency().into(), PLL_SYS_125MHZ, &mut clocks, &mut peripherals.RESETS).map_err(InitError::PllError)?;
let pll_usb = setup_pll_blocking(peripherals.PLL_USB, xosc.operating_frequency().into(), PLL_USB_48MHZ, &mut clocks, &mut peripherals.RESETS).map_err(InitError::PllError)?;

// Configure clocks
// CLK_REF = XOSC (12MHz) / 1 = 12MHz
clocks.reference_clock.configure_clock(&xosc, xosc.get_freq()).map_err(InitError::ClockError)?;

// CLK SYS = PLL SYS (125MHz) / 1 = 125MHz
clocks.system_clock.configure_clock(&pll_sys, pll_sys.get_freq()).map_err(InitError::ClockError)?;

// CLK USB = PLL USB (48MHz) / 1 = 48MHz
clocks.usb_clock.configure_clock(&pll_usb, pll_usb.get_freq()).map_err(InitError::ClockError)?;

// CLK ADC = PLL USB (48MHZ) / 1 = 48MHz
clocks.adc_clock.configure_clock(&pll_usb, pll_usb.get_freq()).map_err(InitError::ClockError)?;

// CLK RTC = PLL USB (48MHz) / 1024 = 46875Hz
clocks.rtc_clock.configure_clock(&pll_usb, 46875u32.Hz()).map_err(InitError::ClockError)?;

// CLK PERI = clk_sys. Used as reference clock for Peripherals. No dividers so just select and enable
// Normally choose clk_sys or clk_usb
clocks.peripheral_clock.configure_clock(&clocks.system_clock, clocks.system_clock.freq()).map_err(InitError::ClockError)?;