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/******************** (C) COPYRIGHT 2008 STMicroelectronics ********************
* File Name : main.c
* Author : MCD Application Team
* Version : V2.0.1
* Date : 06/13/2008
* Description : Main program body.
********************************************************************************
* THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
* WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE TIME.
* AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY DIRECT,
* INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING FROM THE
* CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE CODING
* INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
*******************************************************************************/
/* Includes ------------------------------------------------------------------*/
#include "stm32f10x_lib.h"
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define SP_PROCESS_SIZE 0x200 /* Process stack size */
#define SP_PROCESS 0x02 /* Process stack */
#define SP_MAIN 0x00 /* Main stack */
#define THREAD_MODE_PRIVILEGED 0x00 /* Thread mode has privileged access */
#define THREAD_MODE_UNPRIVILEGED 0x01 /* Thread mode has unprivileged access */
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
ErrorStatus HSEStartUpStatus;
vu8 PSPMemAlloc[SP_PROCESS_SIZE];
vu32 Index = 0, PSPValue = 0, CurrentStack = 0, ThreadMode = 0;
/* Private function prototypes -----------------------------------------------*/
void RCC_Configuration(void);
void NVIC_Configuration(void);
/* Private functions ---------------------------------------------------------*/
/*******************************************************************************
* Function Name : main
* Description : Main program.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
int main(void)
{
#ifdef DEBUG
debug();
#endif
/* Clock configuration */
RCC_Configuration();
/* NVIC configuration */
NVIC_Configuration();
/* Switch Thread mode Stack from Main to Process -----------------------------*/
/* Initialize memory reserved for Process Stack */
for(Index = 0; Index < SP_PROCESS_SIZE; Index++)
{
PSPMemAlloc[Index] = 0x00;
}
/* Set Process stack value */
__MSR_PSP((u32)PSPMemAlloc + SP_PROCESS_SIZE);
/* Select Process Stack as Thread mode Stack */
__MSR_CONTROL(SP_PROCESS);
/* Get the Thread mode stack used */
if((__MRS_CONTROL() & 0x02) == SP_MAIN)
{
/* Main stack is used as the current stack */
CurrentStack = SP_MAIN;
}
else
{
/* Process stack is used as the current stack */
CurrentStack = SP_PROCESS;
/* Get process stack pointer value */
PSPValue = __MRS_PSP();
}
/* Switch Thread mode from privileged to unprivileged ------------------------*/
/* Thread mode has unprivileged access */
__MSR_CONTROL(THREAD_MODE_UNPRIVILEGED | SP_PROCESS);
/* Unprivileged access mainly affect ability to:
- Use or not use certain instructions such as MSR fields
- Access System Control Space (SCS) registers such as NVIC and SysTick */
/* Check Thread mode privilege status */
if((__MRS_CONTROL() & 0x01) == THREAD_MODE_PRIVILEGED)
{
/* Thread mode has privileged access */
ThreadMode = THREAD_MODE_PRIVILEGED;
}
else
{
/* Thread mode has unprivileged access*/
ThreadMode = THREAD_MODE_UNPRIVILEGED;
}
/* Switch back Thread mode from unprivileged to privileged -------------------*/
/* Try to switch back Thread mode to privileged (Not possible, this can be
done only in Handler mode) */
__MSR_CONTROL(THREAD_MODE_PRIVILEGED | SP_PROCESS);
/* Generate a system call exception, and in the ISR switch back Thread mode
to privileged */
__SVC();
/* Check Thread mode privilege status */
if((__MRS_CONTROL() & 0x01) == THREAD_MODE_PRIVILEGED)
{
/* Thread mode has privileged access */
ThreadMode = THREAD_MODE_PRIVILEGED;
}
else
{
/* Thread mode has unprivileged access*/
ThreadMode = THREAD_MODE_UNPRIVILEGED;
}
while (1)
{
}
}
/*******************************************************************************
* Function Name : RCC_Configuration
* Description : Configures the different system clocks.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void RCC_Configuration(void)
{
/* RCC system reset(for debug purpose) */
RCC_DeInit();
/* Enable HSE */
RCC_HSEConfig(RCC_HSE_ON);
/* Wait till HSE is ready */
HSEStartUpStatus = RCC_WaitForHSEStartUp();
if(HSEStartUpStatus == SUCCESS)
{
/* Enable Prefetch Buffer */
FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);
/* Flash 0 wait state */
FLASH_SetLatency(FLASH_Latency_0);
/* HCLK = SYSCLK */
RCC_HCLKConfig(RCC_SYSCLK_Div1);
/* PCLK2 = HCLK */
RCC_PCLK2Config(RCC_HCLK_Div1);
/* PCLK1 = HCLK */
RCC_PCLK1Config(RCC_HCLK_Div1);
/* Select HSE as system clock source */
RCC_SYSCLKConfig(RCC_SYSCLKSource_HSE);
/* Wait till HSE is used as system clock source */
while(RCC_GetSYSCLKSource() != 0x04)
{
}
}
}
/*******************************************************************************
* Function Name : NVIC_Configuration
* Description : Configures NVIC and Vector Table base location.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void NVIC_Configuration(void)
{
#ifdef VECT_TAB_RAM
/* Set the Vector Table base location at 0x20000000 */
NVIC_SetVectorTable(NVIC_VectTab_RAM, 0x0);
#else /* VECT_TAB_FLASH */
/* Set the Vector Table base location at 0x08000000 */
NVIC_SetVectorTable(NVIC_VectTab_FLASH, 0x0);
#endif
}
#ifdef DEBUG
/*******************************************************************************
* Function Name : assert_failed
* Description : Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* Input : - file: pointer to the source file name
* - line: assert_param error line source number
* Output : None
* Return : None
*******************************************************************************/
void assert_failed(u8* file, u32 line)
{
/* User can add his own implementation to report the file name and line number,
ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* Infinite loop */
while (1)
{
}
}
#endif
/******************* (C) COPYRIGHT 2008 STMicroelectronics *****END OF FILE****/
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