system_stm32l5xx_ns.c File Reference

CMSIS Cortex-M33 Device Peripheral Access Layer System Source File to be used in non-secure application when the system implements the TrustZone-M security. More...

#include "stm32l5xx.h"

Macros
#define	VECT_TAB_OFFSET   0x00000000U
#define	VECT_TAB_BASE_ADDRESS   FLASH_BASE_NS

Functions
void	SystemInit (void)
	Setup the microcontroller system.
void	SystemCoreClockUpdate (void)
	Update SystemCoreClock variable according to Clock Register Values.

Variables
uint32_t	SystemCoreClock = 4000000U
const uint8_t	AHBPrescTable [16] = {0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 1U, 2U, 3U, 4U, 6U, 7U, 8U, 9U}
const uint8_t	APBPrescTable [8] = {0U, 0U, 0U, 0U, 1U, 2U, 3U, 4U}
const uint32_t	MSIRangeTable [16]

Detailed Description

CMSIS Cortex-M33 Device Peripheral Access Layer System Source File to be used in non-secure application when the system implements the TrustZone-M security.

Author

MCD Application Team

This file provides two functions and one global variable to be called from user application:

• SystemInit(): This function is called at non-secure startup before branch to non-secure main program. This call is made inside the "startup_stm32l5xx.s" file.
• SystemCoreClock variable: Contains the core clock (HCLK), it can be used by the user application to setup the SysTick timer or configure other parameters.
• SystemCoreClockUpdate(): Updates the variable SystemCoreClock and must be called whenever the core clock is changed during program execution.

After each device reset the MSI (4 MHz) is used as system clock source. Then SystemInit() function is called, in "startup_stm32l5xx.s" file, to configure the system clock before to branch to main secure program. Later, when non-secure SystemInit() function is called, in "startup_stm32l5xx.s" file, the system clock may have been updated from reset value by the main secure program.

Attention

© Copyright (c) 2019 STMicroelectronics. All rights reserved.

This software component is licensed by ST under Apache License, Version 2.0, the "License"; You may not use this file except in compliance with the License. You may obtain a copy of the License at: opensource.org/licenses/Apache-2.0