2 ******************************************************************************
3 * @file system_stm32g4xx.h
4 * @author MCD Application Team
5 * @brief CMSIS Cortex-M4 Device System Source File for STM32G4xx devices.
6 ******************************************************************************
9 * <h2><center>© Copyright (c) 2017 STMicroelectronics.
10 * All rights reserved.</center></h2>
12 * This software component is licensed by ST under BSD 3-Clause license,
13 * the "License"; You may not use this file except in compliance with the
14 * License. You may obtain a copy of the License at:
15 * opensource.org/licenses/BSD-3-Clause
17 ******************************************************************************
25 /** @addtogroup stm32g4xx_system
33 /** @addtogroup STM32G4xx_System_Includes
42 /** @addtogroup STM32G4xx_System_Exported_Variables
45 /* The SystemCoreClock variable is updated in three ways:
46 1) by calling CMSIS function SystemCoreClockUpdate()
47 2) by calling HAL API function HAL_RCC_GetSysClockFreq()
48 3) each time HAL_RCC_ClockConfig() is called to configure the system clock frequency
49 Note: If you use this function to configure the system clock; then there
50 is no need to call the 2 first functions listed above, since SystemCoreClock
51 variable is updated automatically.
53 extern uint32_t SystemCoreClock
; /*!< System Clock Frequency (Core Clock) */
55 extern const uint8_t AHBPrescTable
[16]; /*!< AHB prescalers table values */
56 extern const uint8_t APBPrescTable
[8]; /*!< APB prescalers table values */
62 /** @addtogroup STM32G4xx_System_Exported_Constants
70 /** @addtogroup STM32G4xx_System_Exported_Macros
78 /** @addtogroup STM32G4xx_System_Exported_Functions
82 extern void SystemInit(void);
83 extern void SystemCoreClockUpdate(void);
85 extern void systemClockSetHSEValue(uint32_t frequency
);
86 extern void OverclockRebootIfNecessary(unsigned requestedOverclockLevel
);
87 extern int SystemSYSCLKSource(void);
88 extern int SystemPLLSource(void);
105 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/