Changeset - f7aa98ec64f4
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Ethan Zonca - 10 years ago 2014-07-10 17:23:37
ez@ethanzonca.com
Added system configuration from ST configuration excel file
4 files changed with 404 insertions and 934 deletions:
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libraries/CMSIS/Device/ST/STM32L1xx/Source/Templates/system_stm32l1xx.c
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deleted file
main.c
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#include "main.h"
 
#include "stm32l100c_discovery.h"
 
#include "ssd1306.h"
 
 
static __IO uint32_t TimingDelay;
 
uint8_t BlinkSpeed = 0;
 
 
 
/* Main */
 
int main(void)
 
{
 
   SystemInit();
 
   RCC_ClocksTypeDef RCC_Clocks;
 
  
 
  /* Configure LED3 and LED4 on STM32L100C-Discovery */
 
  STM_EVAL_LEDInit(LED3);
 
  STM_EVAL_LEDInit(LED4);
 
  
 
 
  /* Initialize User_Button on STM32L100C-Discovery */
 
  //STM_EVAL_PBInit(BUTTON_USER, BUTTON_MODE_GPIO);
 
  
 
  /* SysTick end of count event each 1ms */
 
  RCC_GetClocksFreq(&RCC_Clocks);
 
  SysTick_Config(RCC_Clocks.HCLK_Frequency / 1000);
 
 
 /* Initiate Blink Speed variable */ 
 
  BlinkSpeed = 1;
 
 
 /* Init lcd driver */
 
  SSD1303_Init();
 
  SSD1303_DrawPoint(3,3,1);
 
  SSD1303_DrawPoint(5,5,0);
 
//  SSD1303_Init();
 
//  SSD1303_DrawPoint(3,3,1);
 
//  SSD1303_DrawPoint(5,5,0);
 
  
 
  STM_EVAL_LEDOn(LED4);
 
  Delay(1000);
 
  STM_EVAL_LEDOff(LED4);
 
  Delay(1000);
 
 
  while(1)
 
  {  
 
      /* Turn on LD4 Blue LED during 1s each time User button is pressed */
 
      STM_EVAL_LEDOn(LED4);
 
      //STM_EVAL_LEDOn(LED3);
 
      
 
      /* wait for 1s */
 
      Delay(300);
 
      
 
      /* Turn off LD4 Blue LED after 1s each time User button is pressed */
 
      STM_EVAL_LEDOff(LED4);
 
      Delay(300);
 
  }
 
}
 
 
/**
 
  * @brief  Inserts a delay time.
 
  * @param  nTime: specifies the delay time length, in 1 ms.
 
  * @retval None
 
  */
 
void Delay(__IO uint32_t nTime)
 
{
 
  TimingDelay = nTime;
 
 
  while(TimingDelay != 0);
 
}
 
 
/**
 
  * @brief  Decrements the TimingDelay variable.
 
  * @param  None
 
  * @retval None
 
  */
 
void TimingDelay_Decrement(void)
 
{
 
  if (TimingDelay != 0x00)
 
  { 
 
    TimingDelay--;
 
  }
 
}
 
 
#ifdef  USE_FULL_ASSERT
 
 
/**
 
  * @brief  Reports the name of the source file and the source line number
 
  *   where the assert_param error has occurred.
 
  * @param  file: pointer to the source file name
 
  * @param  line: assert_param error line source number
 
  * @retval None
 
  */
 
void assert_failed(uint8_t* file, uint32_t 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
 
ssd1306.c
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/*******************************************************************************
 
* File Name          : SSD1303.c
 
* Author             : lxyppc
 
* Version            : V1.0
 
* Date               : 10-01-21
 
* Description        : SSD1303 operations
 
*                      the SSH1101A is compatible with SSD1303
 
*******************************************************************************/
 
 
/* Includes ------------------------------------------------------------------*/
 
#include "stm32l100c_discovery.h"
 
#include "bsp.h"
 
#include "ssd1306.h"
 
#include "DrawText.h"
 
 
/* Private typedef -----------------------------------------------------------*/
 
/* Private define ------------------------------------------------------------*/
 
#define   SSD1303_PAGE_NUMBER           8
 
#define   SSD1303_COLUMN_NUMBER         128
 
#define   SSD1303_COLUMN_MARGIN_START   2
 
#define   SSD1303_COLUMN_MARGIN_END     2
 
#define   SSD1303_X_PIXEL   128
 
#define   SSD1303_Y_PIXEL   64
 
 
/* Private macro -------------------------------------------------------------*/
 
#define   SSD1303_Buffer    (_SSD1303_Buffer + SSD1303_COLUMN_MARGIN_START)
 
 
/* Private variables ---------------------------------------------------------*/
 
static  uint8_t  _SSD1303_Buffer[SSD1303_COLUMN_NUMBER*SSD1303_PAGE_NUMBER 
 
+ SSD1303_COLUMN_MARGIN_START + SSD1303_COLUMN_MARGIN_END] = {0};
 
static  uint8_t  _SSD1303_Buffer[SSD1303_COLUMN_NUMBER*SSD1303_PAGE_NUMBER + SSD1303_COLUMN_MARGIN_START + SSD1303_COLUMN_MARGIN_END] = {0};
 
static  uint8_t  pageIndex = 0;
 
static  uint8_t  iS_SSD_On = 0;
 
static  uint8_t  pre_on = 0;
 
static  uint8_t  curContrast = 0xCC;
 
static  uint8_t  lastContrast = 0xCC;
 
 
/* Private function prototypes -----------------------------------------------*/
 
void  WriteCommand(unsigned char command);
 
void  WriteData(unsigned char data);
 
void  OnPageTransferDone(void);
 
unsigned long SSD1303_OFF(void);
 
unsigned long SSD1303_ON(void);
 
unsigned char* SSD1303_GetBuffer()
 
{
 
  return SSD1303_Buffer;
 
}
 
/*******************************************************************************
 
* Function Name  : WriteCommand
 
* Description    : Write command to the SSD1303
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
void WriteCommand(unsigned char command)
 
{
 
  SSD_A0_Low();
 
  SPI_SendByte(command);
 
  SPI_Wait();
 
}
 
 
/*******************************************************************************
 
* Function Name  : WriteData
 
* Description    : Write data to the SSD1303
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
void WriteData(unsigned char data)
 
{
 
  SSD_A0_High();
 
  SPI_SendByte(data);
 
  SPI_Wait();
 
}
 
 
/*******************************************************************************
 
* Function Name  : SSD1303_Init
 
* Description    : Initialize the SSD1303
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
void SSD1303_Init(void)
 
{
 
 
  /* Initialize SPI2 */
 
  // TODO
 
 
  /* Generate a reset */
 
  SSD_Reset_Low();
 
  uint32_t i ;
 
  for(i=5000;--i;);
 
  SSD_Reset_High();
 
  
 
  /*************************************************
 
  // SSD1303 Initialization Command
 
  *************************************************/
 
  // Lower Column Address
 
  WriteCommand(0x00); /* Set Lower Column Address */
 
  // High Column Address
 
  WriteCommand(0x10); /* Set Higher Column Address*/
 
  // Display Start Line
 
  WriteCommand(0x40); /* Set Display Start Line */
 
#ifdef    DEBUG_BOARD
 
  curContrast = lastContrast = 0x30;
 
#else
 
  curContrast = lastContrast = 0xCF;
 
#endif
 
  // Contrast Control Register
 
  WriteCommand(0x81); /* Set Contrast Control */
 
  WriteCommand(lastContrast); /* 0 ~ 255 0x1f*/
 
  
 
  // Re-map
 
  WriteCommand(0xA1); /* [A0]:column address 0 is map 
 
  to SEG0 , [A1]: columnaddress 131 is map to SEG0*/ 
 
  // Entire Display ON/OFF
 
  WriteCommand(0xA4); /* A4=ON */
 
  // Normal or Inverse Display
 
  WriteCommand(0XA6); /* Normal Display*/
 
  // Multiplex Ratio
 
  WriteCommand(0xA8); /* Set Multiplex Ratio */
 
  WriteCommand(0x3f); /* Set to 36 Mux*/
 
  // Set DC-DC
 
  WriteCommand(0xAD); /* Set DC-DC */
 
  WriteCommand(0x8B); /* 8B=ON, 8A=Off */
 
  
 
  // Display ON/OFF
 
  WriteCommand(0xAE); /* AF=ON , AE=OFF*/
 
  // Display Offset
 
  WriteCommand(0xD3); /* Set Display Offset */
 
  WriteCommand(0x00); /* No offset */
 
  // Display Clock Divide
 
  WriteCommand(0xD5); /* Set Clock Divide */
 
  WriteCommand(0x20); /* Set to 80Hz */
 
  // Area Color Mode
 
  WriteCommand(0xD8); /* Set Area Color On or Off*/
 
  WriteCommand(0x00); /* Mono Mode */
 
  // COM Pins Hardware Configuration
 
  WriteCommand(0xDA); /* Set Pins HardwareConfiguration */
 
  WriteCommand(0x12);
 
  // VCOMH
 
  WriteCommand(0xDB); /* Set VCOMH */
 
  WriteCommand(0x00);
 
  // VP
 
  WriteCommand(0xD9); /* Set VP */
 
  WriteCommand(0x22); /* P1=2 , P2=2 */
 
  
 
  // Set Common output scan direction
 
  WriteCommand(0xc8);/* Set COM scan direction */
 
  
 
  // For SSD1306 Set the address mode
 
  WriteCommand(0x20);/* Set address mode */
 
  WriteCommand(0x00);/* Set address mode horizontal */
 
  
 
  // Set the page start address
 
  WriteCommand(0xb0);
 
  WriteCommand(0x00);
 
  WriteCommand(0x10);
 
  
 
  /* Turn on the controller */
 
  pre_on = SSD1303_ON();
 
//  // Set Charge pump
 
//  WriteCommand(0x8D); /* Set Charge pump */
 
//  WriteCommand(0x14); /* 0x14=ON, 0x10=Off */
 
//  
 
//  // Turn on the display
 
//  WriteCommand(0xaf);
 
}
 
 
/*******************************************************************************
 
* Function Name  : SSD1303_TurnOff
 
* Description    : Turn off the SSD1303 controller
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
unsigned long SSD1303_TurnOff(void)
 
{
 
  pre_on = 0;
 
  return iS_SSD_On;
 
}
 
 
/*******************************************************************************
 
* Function Name  : SSD1303_TurnOn
 
* Description    : Turn off the SSD1303 controller
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
unsigned long SSD1303_TurnOn(void)
 
{
 
  pre_on = 1;
 
  return iS_SSD_On;
 
}
 
 
/*******************************************************************************
 
* Function Name  : SSD1303_SetContrast
 
* Description    : Set the SSD1303 contrast
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
unsigned char SSD1303_SetContrast(unsigned char contrast)
 
{
 
  curContrast = contrast;
 
  return lastContrast;
 
}
 
 
/*******************************************************************************
 
* Function Name  : SSD1303_GetContrast
 
* Description    : Get the SSD1303 contrast
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
unsigned char SSD1303_GetContrast()
 
{
 
  return lastContrast;
 
}
 
 
/*******************************************************************************
 
* Function Name  : SSD1303_OFF
 
* Description    : Turn off the SSD1303 controller
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
unsigned long SSD1303_OFF(void)
 
{
 
  if(iS_SSD_On){
 
#ifdef  DEBUG_UI
 
    uint32_t i = 0;
 
    for(i=0;i<SSD1303_COLUMN_NUMBER*SSD1303_PAGE_NUMBER;i++){
 
      SSD1303_Buffer[i] = 0;
 
    }
 
#else
 
    // Turn off the display
 
    WriteCommand(0xae);
 
    
 
    // Set Charge pump
 
    WriteCommand(0x8D); /* Set Charge pump */
 
    WriteCommand(0x10); /* 0x14=ON, 0x10=Off */
 
#endif
 
    iS_SSD_On = 0;
 
  }
 
  return iS_SSD_On;
 
}
 
 
 
/*******************************************************************************
 
* Function Name  : SSD1303_ON
 
* Description    : Turn on the SSD1303 controller
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
unsigned long SSD1303_ON(void)
 
{
 
  if(!iS_SSD_On){
 
#ifdef  DEBUG_UI
 
#else
 
  #ifdef    DEBUG_BOARD
 
  #else
 
    // Set Charge pump
 
    WriteCommand(0x8D); /* Set Charge pump */
 
    WriteCommand(0x14); /* 0x14=ON, 0x10=Off */
 
  #endif
 
    // Turn on the display
 
    WriteCommand(0xaf);
 
#endif
 
    iS_SSD_On = 1;
 
  }
 
  return iS_SSD_On;
 
}
 
 
 
/*******************************************************************************
 
* Function Name  : SSD1303_IsOn
 
* Description    : Check whether the SSD1303 is on or off
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
unsigned long SSD1303_IsOn(void)
 
{
 
  return iS_SSD_On;
 
}
 
 
/*******************************************************************************
 
* Function Name  : OnPageTransferDone
 
* Description    : Called when each page transfer done
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
void  OnPageTransferDone(void)
 
{
 
  if(pageIndex == SSD1303_PAGE_NUMBER){
 
    pageIndex = 0;
 
    return;
 
  }
 
#ifdef    DEBUG_BOARD
 
  WriteCommand(0xb0 + pageIndex);
 
  if(pageIndex == 0){
 
    WriteCommand(0x00);
 
    WriteCommand(0x10);
 
  }
 
  SSD_A0_High();
 
  DMA1_Channel5->CCR &= ((uint32_t)0xFFFFFFFE);
 
  DMA1_Channel5->CNDTR = SSD1303_COLUMN_NUMBER+SSD1303_COLUMN_MARGIN_START + SSD1303_COLUMN_MARGIN_END;
 
  DMA1_Channel5->CMAR = (uint32_t)(SSD1303_Buffer+SSD1303_COLUMN_NUMBER*pageIndex - SSD1303_COLUMN_MARGIN_START);
 
  DMA_SSD_1303->CCR |= ((uint32_t)0x00000001);
 
  pageIndex++;
 
#else
 
  SSD_A0_High();
 
  DMA_SSD_1303->CCR &= ((uint32_t)0xFFFFFFFE);
 
  DMA_SSD_1303->CNDTR = SSD1303_COLUMN_NUMBER*SSD1303_PAGE_NUMBER;//+SSD1303_COLUMN_MARGIN_START + SSD1303_COLUMN_MARGIN_END;
 
  DMA_SSD_1303->CMAR = (uint32_t)(SSD1303_Buffer);//+SSD1303_COLUMN_NUMBER*pageIndex);
 
  //DMA_Cmd(DMA_SSD_1303, ENABLE);
 
  DMA_SSD_1303->CCR |= ((uint32_t)0x00000001);
 
//  pageIndex++;
 
  pageIndex = SSD1303_PAGE_NUMBER;
 
#endif
 
}
 
 
/*******************************************************************************
 
* Function Name  : DMA1_Channel5_IRQHandler
 
* Description    : This function handles DMA1 Channel 5 interrupt request.
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
void DMA_Handler_SSD_1303(void) //DMA1_Channel5_IRQHandler(void)
 
{
 
  if(DMA_GetITStatus(DMA1_IT_TC5)){
 
    DMA_ClearITPendingBit(DMA1_IT_GL5);
 
    OnPageTransferDone();
 
  }
 
}
 
 
/*******************************************************************************
 
* Function Name  : StartPageTransfer
 
* Description    : Start a new page transfer
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
void StartPageTransfer(void)
 
{
 
  pageIndex = 0;
 
  if(pre_on){
 
    if(iS_SSD_On == 0){
 
      pre_on = SSD1303_ON();
 
    }
 
  }else{
 
    if(iS_SSD_On){
 
      pre_on = SSD1303_OFF();
 
    }
 
  }
 
  if( curContrast != lastContrast ){
 
    lastContrast = curContrast;
 
    WriteCommand(0x81); /* Set Contrast Control */
 
    WriteCommand(lastContrast); /* 0 ~ 255 0x1f*/
 
  }
 
  
 
  if(iS_SSD_On){
 
    OnPageTransferDone();
 
  }
 
}
 
 
/*******************************************************************************
 
  Display related functions
 
 ******************************************************************************/
 
/*******************************************************************************
 
* Function Name  : SSD1303_DrawBlock
 
* Description    : Draw a block with specify data to SSD1303
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
unsigned long SSD1303_DrawBlock(
 
  Pos_t x,
 
  Pos_t y,
 
  Pos_t cx,
 
  Pos_t cy,
 
  const unsigned char* data)
 
{
 
  if(x >= SSD1303_X_PIXEL)return 0;
 
  if(y >= SSD1303_Y_PIXEL)return 0;
 
  if(x+cx > SSD1303_X_PIXEL ) cx = SSD1303_X_PIXEL - x ;
 
  if(y+cy > SSD1303_Y_PIXEL ) cy = SSD1303_Y_PIXEL - y ;
 
  unsigned char* pStart = SSD1303_Buffer + (y/8)*SSD1303_COLUMN_NUMBER + x;
 
  unsigned char offset1 = y%8;
 
  unsigned char offset2 = (cy+y)%8;
 
  if(data){
 
    unsigned char mask1 = (1<<offset1)-1;
 
    unsigned char mask2 = ~((1<<offset2)-1);
 
    cy = (cy+offset1)/8;
 
   
 
    Pos_t i = 0;
 
    for(i=0;i<cx;i++){
 
      Pos_t j = 0;
 
      unsigned short tmp = *pStart & mask1;
 
      for(;j<cy;j++){
 
        tmp |= (((unsigned short)data[j*cx])<<offset1);
 
        *(pStart + j*SSD1303_COLUMN_NUMBER) = tmp;
 
        tmp>>=8;
 
      }
 
      if(offset2){
 
        tmp |= ((((unsigned short)data[j*cx])<<offset1) & (~mask2))
 
            | *(pStart + j*SSD1303_COLUMN_NUMBER) & mask2;
 
        *(pStart + j*SSD1303_COLUMN_NUMBER) = tmp;
 
      }
 
      data++;
 
      pStart++;
 
    }
 
  }else{
 
    unsigned char mask1 = ~((1<<offset1)-1);
 
    unsigned char mask2 = ((1<<offset2)-1);
 
    cy = (cy+offset1)/8;
 
 
    Pos_t i = 0;
 
    for(i=0;i<cx;i++){
 
      Pos_t j = 1;
 
      *pStart ^= mask1;
 
      for(;j<cy;j++){
 
        *(pStart + j*SSD1303_COLUMN_NUMBER) ^= 0xFF;
 
      }
 
      if(offset2){
 
        *(pStart + j*SSD1303_COLUMN_NUMBER) ^= mask2;
 
      }
 
      pStart++;
 
    }
 
  }
 
  
 
  
 
//  if(!offset){
 
//    for(Pos_t i=0;i<cx;i++){
 
//      unsigned char tmp;
 
//      Pos_t j = 0;
 
//      for(;j<cy/8;j++){
 
//        tmp = data[i+j*cx];
 
//        *(pStart + j*SSD1303_COLUMN_NUMBER + i + x) = tmp;
 
//      }
 
//      if(cy&0x7){
 
//        unsigned char mask1 = (1<<(cy&7)) - 1;
 
//        unsigned char mask2 = 0xFF - mask1;
 
//        tmp = (data[i+j*cx] & mask1)
 
//            | (*(pStart + j*SSD1303_COLUMN_NUMBER + i + x) & mask2);
 
//        *(pStart + j*SSD1303_COLUMN_NUMBER + i + x) = tmp;
 
//      }
 
//    }
 
//  }else{
 
//    for(Pos_t i=0;i<cx;i++){
 
//      unsigned short tmp;
 
//      for(Pos_t j=0;j<cy/8;j++){
 
//        if(j == 0){
 
//          // First line
 
//          tmp = *(pStart + j*SSD1303_COLUMN_NUMBER + i + x) & mask;
 
//        }
 
//        tmp |= (((unsigned short)data[i+j*cx])<<offset);
 
//        *(pStart + j*SSD1303_COLUMN_NUMBER + i + x) = tmp;
 
//        tmp>>=8;
 
//        if(j == (cy/8)-1){
 
//          // Last line
 
//          *(pStart + (j+1)*SSD1303_COLUMN_NUMBER + i + x) &= ~mask;
 
//          *(pStart + (j+1)*SSD1303_COLUMN_NUMBER + i + x) |= tmp;
 
//        }
 
//      }
 
//    }
 
//  }
 
  
 
  return 0;
 
}
 
 
/*******************************************************************************
 
* Function Name  : SSD1303_DrawPoint
 
* Description    : Draw a point with specify data to SSD1303
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
unsigned long SSD1303_DrawPoint(
 
  Pos_t x,
 
  Pos_t y,
 
  Color_t color)
 
{
 
  if(x >= SSD1303_X_PIXEL)return 0;
 
  if(y >= SSD1303_Y_PIXEL)return 0;
 
  unsigned char* pStart = SSD1303_Buffer + (y/8)*SSD1303_COLUMN_NUMBER + x;
 
  unsigned char mask = 1<<(y%8);
 
  if(color){
 
    *pStart |= mask;
 
  }else{
 
    *pStart &= ~mask;
 
  }
 
  return 0;
 
}
 
 
/*******************************************************************************
 
* Function Name  : SSD1303_ReadPoint
 
* Description    : Read a point from SSD1303
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
unsigned long SSD1303_ReadPoint(
 
  Pos_t x,
 
  Pos_t y)
 
{
 
  unsigned char* pStart = SSD1303_Buffer + (y/8)*SSD1303_COLUMN_NUMBER + x;
 
  unsigned char mask = 1<<(y%8);
 
  return *pStart&mask ? 1 : 0;
 
}
 
 
/*******************************************************************************
 
* Function Name  : SSD1303_ClearScreen
 
* Description    : Clear the screen contents
 
* Input          : None
 
* Output         : None
 
* Return         : None
 
*******************************************************************************/
 
void  SSD1303_FillScreen(Color_t color)
 
{
 
  unsigned char mask = color ? 0xFF : 0;
 
  unsigned long i = 0;
 
  for(i=0;i<SSD1303_COLUMN_NUMBER*SSD1303_PAGE_NUMBER;i++){
 
    SSD1303_Buffer[i] = mask;
 
  }
 
}
 
 
const DeviceProp  SSD1303_Prop =
 
{
 
  .pfnDrawBlok = SSD1303_DrawBlock,
 
  .pfnDrawPoint = SSD1303_DrawPoint,
 
  .xPixel = 128,
 
  .yPixel = 64,
 
};
 
system_stm32l1xx.c
Show inline comments
 
/**
 
  ******************************************************************************
 
  * @file    system_stm32l1xx.c
 
  * @author  MCD Application Team
 
  * @version V1.0.0
 
  * @date    29-July-2013
 
  * @brief   CMSIS Cortex-M3 Device Peripheral Access Layer System Source File.
 
  *          This file contains the system clock configuration for STM32L1xx Ultra
 
  *          Low power devices, and is generated by the clock configuration 
 
  *          tool STM32L1xx_Clock_Configuration_V1.1.0.xls
 
  *             
 
  * 1.  This file provides two functions and one global variable to be called from 
 
  *     user application:
 
  *      - SystemInit(): Setups the system clock (System clock source, PLL Multiplier
 
  *                      and Divider factors, AHB/APBx prescalers and Flash settings),
 
  *                      depending on the configuration made in the clock xls tool. 
 
  *                      This function is called at startup just after reset and 
 
  *                      before branch to main program. This call is made inside
 
  *                      the "startup_stm32l1xx_xx.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.   
 
  *      
 
  * 2. After each device reset the MSI (2.1 MHz Range) is used as system clock source.
 
  *    Then SystemInit() function is called, in "startup_stm32l1xx_xx.s" file, to
 
  *    configure the system clock before to branch to main program.    
 
  *    
 
  * 3. If the system clock source selected by user fails to startup, the SystemInit()
 
  *    function will do nothing and MSI still used as system clock source. User can 
 
  *    add some code to deal with this issue inside the SetSysClock() function.       
 
  * 
 
  * 4. The default value of HSE crystal is set to 8MHz, refer to "HSE_VALUE" define
 
  *    in "stm32l1xx.h" file. When HSE is used as system clock source, directly or
 
  *    through PLL, and you are using different crystal you have to adapt the HSE
 
  *    value to your own configuration.
 
  * 
 
  * 5. This file configures the system clock as follows:  
 
  *=============================================================================
 
  *                         System Clock Configuration
 
  *=============================================================================
 
  *        System Clock source          | PLL(HSI)
 
  *----------------------------------------------------------------------------- 
 
  *        SYSCLK                       | 32000000 Hz
 
  *----------------------------------------------------------------------------- 
 
  *        HCLK                         | 32000000 Hz
 
  *----------------------------------------------------------------------------- 
 
  *        AHB Prescaler                | 1
 
  *----------------------------------------------------------------------------- 
 
  *        APB1 Prescaler               | 1
 
  *----------------------------------------------------------------------------- 
 
  *        APB2 Prescaler               | 1
 
  *----------------------------------------------------------------------------- 
 
  *        HSE Frequency                | 8000000 Hz
 
  *----------------------------------------------------------------------------- 
 
  *        PLL DIV                      | 2
 
  *----------------------------------------------------------------------------- 
 
  *        PLL MUL                      | 4
 
  *----------------------------------------------------------------------------- 
 
  *        VDD                          | 3.3 V
 
  *----------------------------------------------------------------------------- 
 
  *        Vcore                        | 1.8 V (Range 1)
 
  *----------------------------------------------------------------------------- 
 
  *        Flash Latency                | 1 WS
 
  *----------------------------------------------------------------------------- 
 
  *        Require 48MHz for USB clock  | Disabled
 
  *----------------------------------------------------------------------------- 
 
  *=============================================================================
 
  ******************************************************************************
 
  * @attention
 
  *
 
  * <h2><center>&copy; COPYRIGHT 2013 STMicroelectronics</center></h2>
 
  *
 
  * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
 
  * You may not use this file except in compliance with the License.
 
  * You may obtain a copy of the License at:
 
  *
 
  *        http://www.st.com/software_license_agreement_liberty_v2
 
  *
 
  * Unless required by applicable law or agreed to in writing, software 
 
  * distributed under the License is distributed on an "AS IS" BASIS, 
 
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 
  * See the License for the specific language governing permissions and
 
  * limitations under the License.
 
  *
 
  ******************************************************************************
 
  */ 
 
 
/** @addtogroup CMSIS
 
  * @{
 
  */
 
 
/** @addtogroup stm32l1xx_system
 
  * @{
 
  */  
 
  
 
/** @addtogroup STM32L1xx_System_Private_Includes
 
  * @{
 
  */
 
 
#include "stm32l1xx.h"
 
 
/**
 
  * @}
 
  */
 
 
/** @addtogroup STM32L1xx_System_Private_TypesDefinitions
 
  * @{
 
  */
 
 
/**
 
  * @}
 
  */
 
 
/** @addtogroup STM32L1xx_System_Private_Defines
 
  * @{
 
  */
 
 
/*!< Uncomment the following line if you need to relocate your vector Table in
 
     Internal SRAM. */ 
 
/* #define VECT_TAB_SRAM */
 
#define VECT_TAB_OFFSET  0x0 /*!< Vector Table base offset field. 
 
                                  This value must be a multiple of 0x200. */
 
/**
 
  * @}
 
  */
 
 
/** @addtogroup STM32L1xx_System_Private_Macros
 
  * @{
 
  */
 
 
/**
 
  * @}
 
  */
 
 
/** @addtogroup STM32L1xx_System_Private_Variables
 
  * @{
 
  */
 
uint32_t SystemCoreClock    = 32000000;
 
__I uint8_t PLLMulTable[9] = {3, 4, 6, 8, 12, 16, 24, 32, 48};
 
__I uint8_t AHBPrescTable[16] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9};
 
 
/**
 
  * @}
 
  */
 
 
/** @addtogroup STM32L1xx_System_Private_FunctionPrototypes
 
  * @{
 
  */
 
 
static void SetSysClock(void);
 
 
/**
 
  * @}
 
  */
 
 
/** @addtogroup STM32L1xx_System_Private_Functions
 
  * @{
 
  */
 
 
/**
 
  * @brief  Setup the microcontroller system.
 
  *         Initialize the Embedded Flash Interface, the PLL and update the 
 
  *         SystemCoreClock variable.
 
  * @param  None
 
  * @retval None
 
  */
 
void SystemInit (void)
 
{
 
  /*!< Set MSION bit */
 
  RCC->CR |= (uint32_t)0x00000100;
 
 
  /*!< Reset SW[1:0], HPRE[3:0], PPRE1[2:0], PPRE2[2:0], MCOSEL[2:0] and MCOPRE[2:0] bits */
 
  RCC->CFGR &= (uint32_t)0x88FFC00C;
 
  
 
  /*!< Reset HSION, HSEON, CSSON and PLLON bits */
 
  RCC->CR &= (uint32_t)0xEEFEFFFE;
 
 
  /*!< Reset HSEBYP bit */
 
  RCC->CR &= (uint32_t)0xFFFBFFFF;
 
 
  /*!< Reset PLLSRC, PLLMUL[3:0] and PLLDIV[1:0] bits */
 
  RCC->CFGR &= (uint32_t)0xFF02FFFF;
 
 
  /*!< Disable all interrupts */
 
  RCC->CIR = 0x00000000;
 
 
  /* Configure the System clock frequency, AHB/APBx prescalers and Flash settings */
 
  SetSysClock();
 
 
#ifdef VECT_TAB_SRAM
 
  SCB->VTOR = SRAM_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal SRAM. */
 
#else
 
  SCB->VTOR = FLASH_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal FLASH. */
 
#endif
 
}
 
 
/**
 
  * @brief  Update SystemCoreClock according to Clock Register Values
 
  *         The SystemCoreClock variable contains the core clock (HCLK), it can
 
  *         be used by the user application to setup the SysTick timer or configure
 
  *         other parameters.
 
  *           
 
  * @note   Each time the core clock (HCLK) changes, this function must be called
 
  *         to update SystemCoreClock variable value. Otherwise, any configuration
 
  *         based on this variable will be incorrect.         
 
  *     
 
  * @note   - The system frequency computed by this function is not the real 
 
  *           frequency in the chip. It is calculated based on the predefined 
 
  *           constant and the selected clock source:
 
  *             
 
  *           - If SYSCLK source is MSI, SystemCoreClock will contain the MSI 
 
  *             value as defined by the MSI range.
 
  *                                   
 
  *           - If SYSCLK source is HSI, SystemCoreClock will contain the HSI_VALUE(*)
 
  *                                              
 
  *           - If SYSCLK source is HSE, SystemCoreClock will contain the HSE_VALUE(**)
 
  *                          
 
  *           - If SYSCLK source is PLL, SystemCoreClock will contain the HSE_VALUE(**) 
 
  *             or HSI_VALUE(*) multiplied/divided by the PLL factors.
 
  *         
 
  *         (*) HSI_VALUE is a constant defined in stm32l1xx.h file (default value
 
  *             16 MHz) but the real value may vary depending on the variations
 
  *             in voltage and temperature.   
 
  *    
 
  *         (**) HSE_VALUE is a constant defined in stm32l1xx.h file (default value
 
  *              8 MHz), user has to ensure that HSE_VALUE is same as the real
 
  *              frequency of the crystal used. Otherwise, this function may
 
  *              have wrong result.
 
  *                
 
  *         - The result of this function could be not correct when using fractional
 
  *           value for HSE crystal.  
 
  * @param  None
 
  * @retval None
 
  */
 
void SystemCoreClockUpdate (void)
 
{
 
  uint32_t tmp = 0, pllmul = 0, plldiv = 0, pllsource = 0, msirange = 0;
 
 
  /* Get SYSCLK source -------------------------------------------------------*/
 
  tmp = RCC->CFGR & RCC_CFGR_SWS;
 
  
 
  switch (tmp)
 
  {
 
    case 0x00:  /* MSI used as system clock */
 
      msirange = (RCC->ICSCR & RCC_ICSCR_MSIRANGE) >> 13;
 
      SystemCoreClock = (32768 * (1 << (msirange + 1)));
 
      break;
 
    case 0x04:  /* HSI used as system clock */
 
      SystemCoreClock = HSI_VALUE;
 
      break;
 
    case 0x08:  /* HSE used as system clock */
 
      SystemCoreClock = HSE_VALUE;
 
      break;
 
    case 0x0C:  /* PLL used as system clock */
 
      /* Get PLL clock source and multiplication factor ----------------------*/
 
      pllmul = RCC->CFGR & RCC_CFGR_PLLMUL;
 
      plldiv = RCC->CFGR & RCC_CFGR_PLLDIV;
 
      pllmul = PLLMulTable[(pllmul >> 18)];
 
      plldiv = (plldiv >> 22) + 1;
 
      
 
      pllsource = RCC->CFGR & RCC_CFGR_PLLSRC;
 
 
      if (pllsource == 0x00)
 
      {
 
        /* HSI oscillator clock selected as PLL clock entry */
 
        SystemCoreClock = (((HSI_VALUE) * pllmul) / plldiv);
 
      }
 
      else
 
      {
 
        /* HSE selected as PLL clock entry */
 
        SystemCoreClock = (((HSE_VALUE) * pllmul) / plldiv);
 
      }
 
      break;
 
    default: /* MSI used as system clock */
 
      msirange = (RCC->ICSCR & RCC_ICSCR_MSIRANGE) >> 13;
 
      SystemCoreClock = (32768 * (1 << (msirange + 1)));
 
      break;
 
  }
 
  /* Compute HCLK clock frequency --------------------------------------------*/
 
  /* Get HCLK prescaler */
 
  tmp = AHBPrescTable[((RCC->CFGR & RCC_CFGR_HPRE) >> 4)];
 
  /* HCLK clock frequency */
 
  SystemCoreClock >>= tmp;
 
}
 
 
/**
 
  * @brief  Configures the System clock frequency, AHB/APBx prescalers and Flash 
 
  *         settings.
 
  * @note   This function should be called only once the RCC clock configuration  
 
  *         is reset to the default reset state (done in SystemInit() function).             
 
  * @param  None
 
  * @retval None
 
  */
 
static void SetSysClock(void)
 
{
 
  __IO uint32_t StartUpCounter = 0, HSIStatus = 0;
 
  
 
  /* SYSCLK, HCLK, PCLK2 and PCLK1 configuration ---------------------------*/
 
  /* Enable HSI */
 
  RCC->CR |= ((uint32_t)RCC_CR_HSION);
 
 
 
  /* Wait till HSI is ready and if Time out is reached exit */
 
  do
 
  {
 
    HSIStatus = RCC->CR & RCC_CR_HSIRDY;
 
  } while((HSIStatus == 0) && (StartUpCounter != HSI_STARTUP_TIMEOUT));
 
 
  if ((RCC->CR & RCC_CR_HSIRDY) != RESET)
 
  {
 
    HSIStatus = (uint32_t)0x01;
 
  }
 
  else
 
  {
 
    HSIStatus = (uint32_t)0x00;
 
  }
 
    
 
  if (HSIStatus == (uint32_t)0x01)
 
  {
 
    /* Enable 64-bit access */
 
    FLASH->ACR |= FLASH_ACR_ACC64;
 
    
 
    /* Enable Prefetch Buffer */
 
    FLASH->ACR |= FLASH_ACR_PRFTEN;
 
 
    /* Flash 1 wait state */
 
    FLASH->ACR |= FLASH_ACR_LATENCY;
 
    
 
 
    /* Power enable */
 
    RCC->APB1ENR |= RCC_APB1ENR_PWREN;
 
  
 
    /* Select the Voltage Range 1 (1.8 V) */
 
    PWR->CR = PWR_CR_VOS_0;
 
  
 
  
 
    /* Wait Until the Voltage Regulator is ready */
 
    while((PWR->CSR & PWR_CSR_VOSF) != RESET)
 
    {
 
    }
 
      
 
    /* HCLK = SYSCLK /1*/
 
    RCC->CFGR |= (uint32_t)RCC_CFGR_HPRE_DIV1;
 
  
 
    /* PCLK2 = HCLK /1*/
 
    RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE2_DIV1;
 
    
 
    /* PCLK1 = HCLK /1*/
 
    RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE1_DIV1;
 
    
 
    /*  PLL configuration */
 
    RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_PLLSRC | RCC_CFGR_PLLMUL |
 
                                        RCC_CFGR_PLLDIV));
 
    RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLSRC_HSI | RCC_CFGR_PLLMUL4 | RCC_CFGR_PLLDIV2);
 
 
    /* Enable PLL */
 
    RCC->CR |= RCC_CR_PLLON;
 
 
    /* Wait till PLL is ready */
 
    while((RCC->CR & RCC_CR_PLLRDY) == 0)
 
    {
 
    }
 
        
 
    /* Select PLL as system clock source */
 
    RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_SW));
 
    RCC->CFGR |= (uint32_t)RCC_CFGR_SW_PLL;
 
 
    /* Wait till PLL is used as system clock source */
 
    while ((RCC->CFGR & (uint32_t)RCC_CFGR_SWS) != (uint32_t)RCC_CFGR_SWS_PLL)
 
    {
 
    }
 
  }
 
  else
 
  {
 
    /* If HSI fails to start-up, the application will have wrong clock
 
       configuration. User can add here some code to deal with this error */
 
  }
 
}
 
 
/**
 
  * @}
 
  */
 
 
/**
 
  * @}
 
  */
 
 
/**
 
  * @}
 
  */
 
 
/******************* (C) COPYRIGHT 2013 STMicroelectronics *****END OF FILE****/
 
/**
 
  ******************************************************************************
 
  * @file    system_stm32l1xx.c
 
  * @author  MCD Application Team
 
  * @version V1.2.0
 
  * @date    10-July-2014
 
  * @brief   CMSIS Cortex-M3 Device Peripheral Access Layer System Source File.
 
  *          This file contains the system clock configuration for STM32L1xx Ultra
 
  *          Low power devices, and is generated by the clock configuration 
 
  *          tool  STM32L1xx_Clock_Configuration_V1.2.0.xls
 
  *             
 
  * 1.  This file provides two functions and one global variable to be called from 
 
  *     user application:
 
  *      - SystemInit(): Setups the system clock (System clock source, PLL Multiplier
 
  *                      and Divider factors, AHB/APBx prescalers and Flash settings),
 
  *                      depending on the configuration made in the clock xls tool. 
 
  *                      This function is called at startup just after reset and 
 
  *                      before branch to main program. This call is made inside
 
  *                      the "startup_stm32l1xx_xx.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.   
 
  *      
 
  * 2. After each device reset the MSI (2.1 MHz Range) is used as system clock source.
 
  *    Then SystemInit() function is called, in "startup_stm32l1xx_xx.s" file, to
 
  *    configure the system clock before to branch to main program.    
 
  *    
 
  * 3. If the system clock source selected by user fails to startup, the SystemInit()
 
  *    function will do nothing and MSI still used as system clock source. User can 
 
  *    add some code to deal with this issue inside the SetSysClock() function.       
 
  * 
 
  * 4. The default value of HSE crystal is set to 8MHz, refer to "HSE_VALUE" define
 
  *    in "stm32l1xx.h" file. When HSE is used as system clock source, directly or
 
  *    through PLL, and you are using different crystal you have to adapt the HSE
 
  *    value to your own configuration.
 
  * 
 
  * 5. This file configures the system clock as follows:  
 
  *=============================================================================
 
  *                         System Clock Configuration
 
  *=============================================================================
 
  *        System Clock source          | PLL(HSE)
 
  *----------------------------------------------------------------------------- 
 
  *        SYSCLK                       | 32000000 Hz
 
  *----------------------------------------------------------------------------- 
 
  *        HCLK                         | 32000000 Hz
 
  *----------------------------------------------------------------------------- 
 
  *        AHB Prescaler                | 1
 
  *----------------------------------------------------------------------------- 
 
  *        APB1 Prescaler               | 1
 
  *----------------------------------------------------------------------------- 
 
  *        APB2 Prescaler               | 1
 
  *----------------------------------------------------------------------------- 
 
  *        HSE Frequency                | 8000000 Hz
 
  *----------------------------------------------------------------------------- 
 
  *        PLL DIV                      | 3
 
  *----------------------------------------------------------------------------- 
 
  *        PLL MUL                      | 12
 
  *----------------------------------------------------------------------------- 
 
  *        VDD                          | 3.3 V
 
  *----------------------------------------------------------------------------- 
 
  *        Vcore                        | 1.8 V (Range 1)
 
  *----------------------------------------------------------------------------- 
 
  *        Flash Latency                | 1 WS
 
  *----------------------------------------------------------------------------- 
 
  *        Require 48MHz for USB clock  | Enabled
 
  *----------------------------------------------------------------------------- 
 
  *=============================================================================
 
  * @attention
 
  *
 
  * <h2><center>&copy; COPYRIGHT 2013 STMicroelectronics</center></h2>
 
  *
 
  * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
 
  * You may not use this file except in compliance with the License.
 
  * You may obtain a copy of the License at:
 
  *
 
  *        http://www.st.com/software_license_agreement_liberty_v2
 
  *
 
  * Unless required by applicable law or agreed to in writing, software 
 
  * distributed under the License is distributed on an "AS IS" BASIS, 
 
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 
  * See the License for the specific language governing permissions and
 
  * limitations under the License.
 
  *
 
  ******************************************************************************
 
  */
 

	
 
/** @addtogroup CMSIS
 
  * @{
 
  */
 

	
 
/** @addtogroup stm32l1xx_system
 
  * @{
 
  */  
 
  
 
/** @addtogroup STM32L1xx_System_Private_Includes
 
  * @{
 
  */
 

	
 
#include "stm32l1xx.h"
 

	
 
/**
 
  * @}
 
  */
 

	
 
/** @addtogroup STM32L1xx_System_Private_TypesDefinitions
 
  * @{
 
  */
 

	
 
/**
 
  * @}
 
  */
 

	
 
/** @addtogroup STM32L1xx_System_Private_Defines
 
  * @{
 
  */
 

	
 
/*!< Uncomment the following line if you need to relocate your vector Table in
 
     Internal SRAM. */ 
 
/* #define VECT_TAB_SRAM */
 
#define VECT_TAB_OFFSET  0x0 /*!< Vector Table base offset field. 
 
                                  This value must be a multiple of 0x200. */
 
/**
 
  * @}
 
  */
 

	
 
/** @addtogroup STM32L1xx_System_Private_Macros
 
  * @{
 
  */
 

	
 
/**
 
  * @}
 
  */
 

	
 
/** @addtogroup STM32L1xx_System_Private_Variables
 
  * @{
 
  */
 
uint32_t SystemCoreClock    = 32000000;
 
__I uint8_t PLLMulTable[9] = {3, 4, 6, 8, 12, 16, 24, 32, 48};
 
__I uint8_t AHBPrescTable[16] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9};
 

	
 
/**
 
  * @}
 
  */
 

	
 
/** @addtogroup STM32L1xx_System_Private_FunctionPrototypes
 
  * @{
 
  */
 

	
 
static void SetSysClock(void);
 

	
 
/**
 
  * @}
 
  */
 

	
 
/** @addtogroup STM32L1xx_System_Private_Functions
 
  * @{
 
  */
 

	
 
/**
 
  * @brief  Setup the microcontroller system.
 
  *         Initialize the Embedded Flash Interface, the PLL and update the 
 
  *         SystemCoreClock variable.
 
  * @param  None
 
  * @retval None
 
  */
 
void SystemInit (void)
 
{
 
  /*!< Set MSION bit */
 
  RCC->CR |= (uint32_t)0x00000100;
 

	
 
  /*!< Reset SW[1:0], HPRE[3:0], PPRE1[2:0], PPRE2[2:0], MCOSEL[2:0] and MCOPRE[2:0] bits */
 
  RCC->CFGR &= (uint32_t)0x88FFC00C;
 
  
 
  /*!< Reset HSION, HSEON, CSSON and PLLON bits */
 
  RCC->CR &= (uint32_t)0xEEFEFFFE;
 

	
 
  /*!< Reset HSEBYP bit */
 
  RCC->CR &= (uint32_t)0xFFFBFFFF;
 

	
 
  /*!< Reset PLLSRC, PLLMUL[3:0] and PLLDIV[1:0] bits */
 
  RCC->CFGR &= (uint32_t)0xFF02FFFF;
 

	
 
  /*!< Disable all interrupts */
 
  RCC->CIR = 0x00000000;
 

	
 
  /* Configure the System clock frequency, AHB/APBx prescalers and Flash settings */
 
  SetSysClock();
 

	
 
#ifdef VECT_TAB_SRAM
 
  SCB->VTOR = SRAM_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal SRAM. */
 
#else
 
  SCB->VTOR = FLASH_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal FLASH. */
 
#endif
 
}
 

	
 
/**
 
  * @brief  Update SystemCoreClock according to Clock Register Values
 
  *         The SystemCoreClock variable contains the core clock (HCLK), it can
 
  *         be used by the user application to setup the SysTick timer or configure
 
  *         other parameters.
 
  *           
 
  * @note   Each time the core clock (HCLK) changes, this function must be called
 
  *         to update SystemCoreClock variable value. Otherwise, any configuration
 
  *         based on this variable will be incorrect.         
 
  *     
 
  * @note   - The system frequency computed by this function is not the real 
 
  *           frequency in the chip. It is calculated based on the predefined 
 
  *           constant and the selected clock source:
 
  *             
 
  *           - If SYSCLK source is MSI, SystemCoreClock will contain the MSI 
 
  *             value as defined by the MSI range.
 
  *                                   
 
  *           - If SYSCLK source is HSI, SystemCoreClock will contain the HSI_VALUE(*)
 
  *                                              
 
  *           - If SYSCLK source is HSE, SystemCoreClock will contain the HSE_VALUE(**)
 
  *                          
 
  *           - If SYSCLK source is PLL, SystemCoreClock will contain the HSE_VALUE(**) 
 
  *             or HSI_VALUE(*) multiplied/divided by the PLL factors.
 
  *         
 
  *         (*) HSI_VALUE is a constant defined in stm32l1xx.h file (default value
 
  *             16 MHz) but the real value may vary depending on the variations
 
  *             in voltage and temperature.   
 
  *    
 
  *         (**) HSE_VALUE is a constant defined in stm32l1xx.h file (default value
 
  *              8 MHz), user has to ensure that HSE_VALUE is same as the real
 
  *              frequency of the crystal used. Otherwise, this function may
 
  *              have wrong result.
 
  *                
 
  *         - The result of this function could be not correct when using fractional
 
  *           value for HSE crystal.  
 
  * @param  None
 
  * @retval None
 
  */
 
void SystemCoreClockUpdate (void)
 
{
 
  uint32_t tmp = 0, pllmul = 0, plldiv = 0, pllsource = 0, msirange = 0;
 

	
 
  /* Get SYSCLK source -------------------------------------------------------*/
 
  tmp = RCC->CFGR & RCC_CFGR_SWS;
 
  
 
  switch (tmp)
 
  {
 
    case 0x00:  /* MSI used as system clock */
 
      msirange = (RCC->ICSCR & RCC_ICSCR_MSIRANGE) >> 13;
 
      SystemCoreClock = (32768 * (1 << (msirange + 1)));
 
      break;
 
    case 0x04:  /* HSI used as system clock */
 
      SystemCoreClock = HSI_VALUE;
 
      break;
 
    case 0x08:  /* HSE used as system clock */
 
      SystemCoreClock = HSE_VALUE;
 
      break;
 
    case 0x0C:  /* PLL used as system clock */
 
      /* Get PLL clock source and multiplication factor ----------------------*/
 
      pllmul = RCC->CFGR & RCC_CFGR_PLLMUL;
 
      plldiv = RCC->CFGR & RCC_CFGR_PLLDIV;
 
      pllmul = PLLMulTable[(pllmul >> 18)];
 
      plldiv = (plldiv >> 22) + 1;
 
      
 
      pllsource = RCC->CFGR & RCC_CFGR_PLLSRC;
 

	
 
      if (pllsource == 0x00)
 
      {
 
        /* HSI oscillator clock selected as PLL clock entry */
 
        SystemCoreClock = (((HSI_VALUE) * pllmul) / plldiv);
 
      }
 
      else
 
      {
 
        /* HSE selected as PLL clock entry */
 
        SystemCoreClock = (((HSE_VALUE) * pllmul) / plldiv);
 
      }
 
      break;
 
    default: /* MSI used as system clock */
 
      msirange = (RCC->ICSCR & RCC_ICSCR_MSIRANGE) >> 13;
 
      SystemCoreClock = (32768 * (1 << (msirange + 1)));
 
      break;
 
  }
 
  /* Compute HCLK clock frequency --------------------------------------------*/
 
  /* Get HCLK prescaler */
 
  tmp = AHBPrescTable[((RCC->CFGR & RCC_CFGR_HPRE) >> 4)];
 
  /* HCLK clock frequency */
 
  SystemCoreClock >>= tmp;
 
}
 

	
 
/**
 
  * @brief  Configures the System clock frequency, AHB/APBx prescalers and Flash 
 
  *         settings.
 
  * @note   This function should be called only once the RCC clock configuration  
 
  *         is reset to the default reset state (done in SystemInit() function).             
 
  * @param  None
 
  * @retval None
 
  */
 
static void SetSysClock(void)
 
{
 
  __IO uint32_t StartUpCounter = 0, HSEStatus = 0;
 
  
 
  /* SYSCLK, HCLK, PCLK2 and PCLK1 configuration ---------------------------*/
 
  /* Enable HSE */
 
  RCC->CR |= ((uint32_t)RCC_CR_HSEON);
 
 
 
  /* Wait till HSE is ready and if Time out is reached exit */
 
  do
 
  {
 
    HSEStatus = RCC->CR & RCC_CR_HSERDY;
 
    StartUpCounter++;
 
  } while((HSEStatus == 0) && (StartUpCounter != HSE_STARTUP_TIMEOUT));
 

	
 
  if ((RCC->CR & RCC_CR_HSERDY) != RESET)
 
  {
 
    HSEStatus = (uint32_t)0x01;
 
  }
 
  else
 
  {
 
    HSEStatus = (uint32_t)0x00;
 
  }
 
  
 
  if (HSEStatus == (uint32_t)0x01)
 
  {
 
    /* Enable 64-bit access */
 
    FLASH->ACR |= FLASH_ACR_ACC64;
 
    
 
    /* Enable Prefetch Buffer */
 
    FLASH->ACR |= FLASH_ACR_PRFTEN;
 

	
 
    /* Flash 1 wait state */
 
    FLASH->ACR |= FLASH_ACR_LATENCY;
 
    
 
    /* Power enable */
 
    RCC->APB1ENR |= RCC_APB1ENR_PWREN;
 
  
 
    /* Select the Voltage Range 1 (1.8 V) */
 
    PWR->CR = PWR_CR_VOS_0;
 
  
 
    /* Wait Until the Voltage Regulator is ready */
 
    while((PWR->CSR & PWR_CSR_VOSF) != RESET)
 
    {
 
    }
 
        
 
    /* HCLK = SYSCLK /1*/
 
    RCC->CFGR |= (uint32_t)RCC_CFGR_HPRE_DIV1;
 
  
 
    /* PCLK2 = HCLK /1*/
 
    RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE2_DIV1;
 
    
 
    /* PCLK1 = HCLK /1*/
 
    RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE1_DIV1;
 
    
 
    /*  PLL configuration */
 
    RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_PLLSRC | RCC_CFGR_PLLMUL |
 
                                        RCC_CFGR_PLLDIV));
 
    RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLSRC_HSE | RCC_CFGR_PLLMUL12 | RCC_CFGR_PLLDIV3);
 

	
 
    /* Enable PLL */
 
    RCC->CR |= RCC_CR_PLLON;
 

	
 
    /* Wait till PLL is ready */
 
    while((RCC->CR & RCC_CR_PLLRDY) == 0)
 
    {
 
    }
 
        
 
    /* Select PLL as system clock source */
 
    RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_SW));
 
    RCC->CFGR |= (uint32_t)RCC_CFGR_SW_PLL;
 

	
 
    /* Wait till PLL is used as system clock source */
 
    while ((RCC->CFGR & (uint32_t)RCC_CFGR_SWS) != (uint32_t)RCC_CFGR_SWS_PLL)
 
    {
 
    }
 
  }
 
  else
 
  {
 
    /* If HSE fails to start-up, the application will have wrong clock
 
       configuration. User can add here some code to deal with this error */
 
  }
 
}
 

	
 
/**
 
  * @}
 
  */
 

	
 
/**
 
  * @}
 
  */
 

	
 
/**
 
  * @}
 
  */
 

	
 
/******************* (C) COPYRIGHT 2013 STMicroelectronics *****END OF FILE****/
 

	
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