clock.c File Reference

Cortex-M4 (STM32F4) Clock HAL Implementation. More...

#include "core/cortex-m4/clock.h"
#include "core/cortex-m4/flash_reg.h"
#include "core/cortex-m4/rcc_reg.h"
#include <stdint.h>

Include dependency graph for clock.c:

Functions
void	hal_clock_init (hal_clock_config_t *cfg, hal_pll_config_t *pll_cfg)
	Initialize system clock and bus prescalers.
uint32_t	hal_clock_get_sysclk (void)
	Get current system clock (SYSCLK) frequency.
uint32_t	hal_clock_get_ahbclk (void)
	Get current AHB bus frequency.
uint32_t	hal_clock_get_apb1clk (void)
	Get current APB1 bus frequency.
uint32_t	hal_clock_get_apb2clk (void)
	Get current APB2 bus frequency.

Detailed Description

Cortex-M4 (STM32F4) Clock HAL Implementation.

This file provides a hardware abstraction layer for clock configuration on STM32F4 microcontrollers. It includes functions to:

• Initialize system clock sources (HSI, HSE, PLL)
• Configure PLL parameters (M, N, P, Q factors)
• Set AHB/APB bus prescalers
• Manage flash wait states
• Retrieve current clock frequencies for all system buses

Note

The implementation assumes an STM32F4xx microcontroller and uses direct register access for maximum performance and minimal overhead.

Copyright

© NAVROBOTEC PVT. LTD.

Function Documentation

hal_clock_get_ahbclk()

uint32_t hal_clock_get_ahbclk

(

void

)

Get current AHB bus frequency.

Get the AHB bus clock frequency.

Returns

AHB clock frequency in Hz

hal_clock_get_apb1clk()

uint32_t hal_clock_get_apb1clk

(

void

)

Get current APB1 bus frequency.

Get the APB1 bus clock frequency.

Returns

APB1 clock frequency in Hz

hal_clock_get_apb2clk()

uint32_t hal_clock_get_apb2clk

(

void

)

Get current APB2 bus frequency.

Get the APB2 bus clock frequency.

Returns

APB2 clock frequency in Hz

hal_clock_get_sysclk()

uint32_t hal_clock_get_sysclk

(

void

)

Get current system clock (SYSCLK) frequency.

Get the system clock frequency (SYSCLK).

Returns

SYSCLK frequency in Hz

Determines SYSCLK frequency based on current clock source:

• HSI: Fixed 16 MHz
• HSE: Fixed 8 MHz
• PLL: Calculated from PLL configuration registers

hal_clock_init()

void hal_clock_init	(	hal_clock_config_t *	cfg,
		hal_pll_config_t *	pll_cfg )

Initialize system clock and bus prescalers.

Initialize the system clock.

Parameters

[in]	cfg	Pointer to clock configuration structure
[in]	pll_cfg	Pointer to PLL configuration structure (required if using PLL)

Configures the complete clock tree including:

• Clock source selection (HSI/HSE/PLL)
• PLL configuration (when used)
• Flash latency settings
• AHB/APB prescalers

Note

This function will block until clock switches are complete

< Flash Interface base address

< Flash ACR Latency bit position

< Flash ACR Latency bit position