/** | |
****************************************************************************** | |
* @file system_stm32f1xx.c | |
* @author MCD Application Team | |
* @version V4.1.0 | |
* @date 29-April-2016 | |
* @brief CMSIS Cortex-M3 Device Peripheral Access Layer System Source File. | |
* | |
* 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 | |
* factors, AHB/APBx prescalers and Flash settings). | |
* This function is called at startup just after reset and | |
* before branch to main program. This call is made inside | |
* the "startup_stm32f1xx_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 HSI (8 MHz) is used as system clock source. | |
* Then SystemInit() function is called, in "startup_stm32f1xx_xx.s" file, to | |
* configure the system clock before to branch to main program. | |
* | |
* 4. The default value of HSE crystal is set to 8 MHz (or 25 MHz, depending on | |
* the product used), refer to "HSE_VALUE". | |
* 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. | |
* | |
****************************************************************************** | |
* @attention | |
* | |
* <h2><center>© COPYRIGHT(c) 2016 STMicroelectronics</center></h2> | |
* | |
* Redistribution and use in source and binary forms, with or without modification, | |
* are permitted provided that the following conditions are met: | |
* 1. Redistributions of source code must retain the above copyright notice, | |
* this list of conditions and the following disclaimer. | |
* 2. Redistributions in binary form must reproduce the above copyright notice, | |
* this list of conditions and the following disclaimer in the documentation | |
* and/or other materials provided with the distribution. | |
* 3. Neither the name of STMicroelectronics nor the names of its contributors | |
* may be used to endorse or promote products derived from this software | |
* without specific prior written permission. | |
* | |
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" | |
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE | |
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE | |
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR | |
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER | |
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, | |
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | |
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
* | |
****************************************************************************** | |
*/ | |
/** @addtogroup CMSIS | |
* @{ | |
*/ | |
/** @addtogroup stm32f1xx_system | |
* @{ | |
*/ | |
/** @addtogroup STM32F1xx_System_Private_Includes | |
* @{ | |
*/ | |
#include "stm32f1xx.h" | |
/** | |
* @} | |
*/ | |
/** @addtogroup STM32F1xx_System_Private_TypesDefinitions | |
* @{ | |
*/ | |
/** | |
* @} | |
*/ | |
/** @addtogroup STM32F1xx_System_Private_Defines | |
* @{ | |
*/ | |
#if !defined (HSE_VALUE) | |
#define HSE_VALUE ((uint32_t)8000000) /*!< Default value of the External oscillator in Hz. | |
This value can be provided and adapted by the user application. */ | |
#endif /* HSE_VALUE */ | |
#if !defined (HSI_VALUE) | |
#define HSI_VALUE ((uint32_t)8000000) /*!< Default value of the Internal oscillator in Hz. | |
This value can be provided and adapted by the user application. */ | |
#endif /* HSI_VALUE */ | |
/*!< Uncomment the following line if you need to use external SRAM */ | |
#if defined(STM32F100xE) || defined(STM32F101xE) || defined(STM32F101xG) || defined(STM32F103xE) || defined(STM32F103xG) | |
/* #define DATA_IN_ExtSRAM */ | |
#endif /* STM32F100xE || STM32F101xE || STM32F101xG || STM32F103xE || STM32F103xG */ | |
/*!< 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 STM32F1xx_System_Private_Macros | |
* @{ | |
*/ | |
/** | |
* @} | |
*/ | |
/** @addtogroup STM32F1xx_System_Private_Variables | |
* @{ | |
*/ | |
/******************************************************************************* | |
* Clock Definitions | |
*******************************************************************************/ | |
#if defined(STM32F100xB) ||defined(STM32F100xE) | |
uint32_t SystemCoreClock = 24000000; /*!< System Clock Frequency (Core Clock) */ | |
#else /*!< HSI Selected as System Clock source */ | |
uint32_t SystemCoreClock = 72000000; /*!< System Clock Frequency (Core Clock) */ | |
#endif | |
const uint8_t AHBPrescTable[16] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9}; | |
const uint8_t APBPrescTable[8] = {0, 0, 0, 0, 1, 2, 3, 4}; | |
/** | |
* @} | |
*/ | |
/** @addtogroup STM32F1xx_System_Private_FunctionPrototypes | |
* @{ | |
*/ | |
#if defined(STM32F100xE) || defined(STM32F101xE) || defined(STM32F101xG) || defined(STM32F103xE) || defined(STM32F103xG) | |
#ifdef DATA_IN_ExtSRAM | |
static void SystemInit_ExtMemCtl(void); | |
#endif /* DATA_IN_ExtSRAM */ | |
#endif /* STM32F100xE || STM32F101xE || STM32F101xG || STM32F103xE || STM32F103xG */ | |
/** | |
* @} | |
*/ | |
/** @addtogroup STM32F1xx_System_Private_Functions | |
* @{ | |
*/ | |
/** | |
* @brief Setup the microcontroller system | |
* Initialize the Embedded Flash Interface, the PLL and update the | |
* SystemCoreClock variable. | |
* @note This function should be used only after reset. | |
* @param None | |
* @retval None | |
*/ | |
void SystemInit (void) | |
{ | |
/* Reset the RCC clock configuration to the default reset state(for debug purpose) */ | |
/* Set HSION bit */ | |
RCC->CR |= (uint32_t)0x00000001; | |
/* Reset SW, HPRE, PPRE1, PPRE2, ADCPRE and MCO bits */ | |
#if !defined(STM32F105xC) && !defined(STM32F107xC) | |
RCC->CFGR &= (uint32_t)0xF8FF0000; | |
#else | |
RCC->CFGR &= (uint32_t)0xF0FF0000; | |
#endif /* STM32F105xC */ | |
/* Reset HSEON, CSSON and PLLON bits */ | |
RCC->CR &= (uint32_t)0xFEF6FFFF; | |
/* Reset HSEBYP bit */ | |
RCC->CR &= (uint32_t)0xFFFBFFFF; | |
/* Reset PLLSRC, PLLXTPRE, PLLMUL and USBPRE/OTGFSPRE bits */ | |
RCC->CFGR &= (uint32_t)0xFF80FFFF; | |
#if defined(STM32F105xC) || defined(STM32F107xC) | |
/* Reset PLL2ON and PLL3ON bits */ | |
RCC->CR &= (uint32_t)0xEBFFFFFF; | |
/* Disable all interrupts and clear pending bits */ | |
RCC->CIR = 0x00FF0000; | |
/* Reset CFGR2 register */ | |
RCC->CFGR2 = 0x00000000; | |
#elif defined(STM32F100xB) || defined(STM32F100xE) | |
/* Disable all interrupts and clear pending bits */ | |
RCC->CIR = 0x009F0000; | |
/* Reset CFGR2 register */ | |
RCC->CFGR2 = 0x00000000; | |
#else | |
/* Disable all interrupts and clear pending bits */ | |
RCC->CIR = 0x009F0000; | |
#endif /* STM32F105xC */ | |
#if defined(STM32F100xE) || defined(STM32F101xE) || defined(STM32F101xG) || defined(STM32F103xE) || defined(STM32F103xG) | |
#ifdef DATA_IN_ExtSRAM | |
SystemInit_ExtMemCtl(); | |
#endif /* DATA_IN_ExtSRAM */ | |
#endif | |
#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 variable 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 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 by the PLL factors. | |
* | |
* (*) HSI_VALUE is a constant defined in stm32f1xx.h file (default value | |
* 8 MHz) but the real value may vary depending on the variations | |
* in voltage and temperature. | |
* | |
* (**) HSE_VALUE is a constant defined in stm32f1xx.h file (default value | |
* 8 MHz or 25 MHz, depending on the product used), 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, pllmull = 0, pllsource = 0; | |
#if defined(STM32F105xC) || defined(STM32F107xC) | |
uint32_t prediv1source = 0, prediv1factor = 0, prediv2factor = 0, pll2mull = 0; | |
#endif /* STM32F105xC */ | |
#if defined(STM32F100xB) || defined(STM32F100xE) | |
uint32_t prediv1factor = 0; | |
#endif /* STM32F100xB or STM32F100xE */ | |
/* Get SYSCLK source -------------------------------------------------------*/ | |
tmp = RCC->CFGR & RCC_CFGR_SWS; | |
switch (tmp) | |
{ | |
case 0x00: /* HSI used as system clock */ | |
SystemCoreClock = HSI_VALUE; | |
break; | |
case 0x04: /* HSE used as system clock */ | |
SystemCoreClock = HSE_VALUE; | |
break; | |
case 0x08: /* PLL used as system clock */ | |
/* Get PLL clock source and multiplication factor ----------------------*/ | |
pllmull = RCC->CFGR & RCC_CFGR_PLLMULL; | |
pllsource = RCC->CFGR & RCC_CFGR_PLLSRC; | |
#if !defined(STM32F105xC) && !defined(STM32F107xC) | |
pllmull = ( pllmull >> 18) + 2; | |
if (pllsource == 0x00) | |
{ | |
/* HSI oscillator clock divided by 2 selected as PLL clock entry */ | |
SystemCoreClock = (HSI_VALUE >> 1) * pllmull; | |
} | |
else | |
{ | |
#if defined(STM32F100xB) || defined(STM32F100xE) | |
prediv1factor = (RCC->CFGR2 & RCC_CFGR2_PREDIV1) + 1; | |
/* HSE oscillator clock selected as PREDIV1 clock entry */ | |
SystemCoreClock = (HSE_VALUE / prediv1factor) * pllmull; | |
#else | |
/* HSE selected as PLL clock entry */ | |
if ((RCC->CFGR & RCC_CFGR_PLLXTPRE) != (uint32_t)RESET) | |
{/* HSE oscillator clock divided by 2 */ | |
SystemCoreClock = (HSE_VALUE >> 1) * pllmull; | |
} | |
else | |
{ | |
SystemCoreClock = HSE_VALUE * pllmull; | |
} | |
#endif | |
} | |
#else | |
pllmull = pllmull >> 18; | |
if (pllmull != 0x0D) | |
{ | |
pllmull += 2; | |
} | |
else | |
{ /* PLL multiplication factor = PLL input clock * 6.5 */ | |
pllmull = 13 / 2; | |
} | |
if (pllsource == 0x00) | |
{ | |
/* HSI oscillator clock divided by 2 selected as PLL clock entry */ | |
SystemCoreClock = (HSI_VALUE >> 1) * pllmull; | |
} | |
else | |
{/* PREDIV1 selected as PLL clock entry */ | |
/* Get PREDIV1 clock source and division factor */ | |
prediv1source = RCC->CFGR2 & RCC_CFGR2_PREDIV1SRC; | |
prediv1factor = (RCC->CFGR2 & RCC_CFGR2_PREDIV1) + 1; | |
if (prediv1source == 0) | |
{ | |
/* HSE oscillator clock selected as PREDIV1 clock entry */ | |
SystemCoreClock = (HSE_VALUE / prediv1factor) * pllmull; | |
} | |
else | |
{/* PLL2 clock selected as PREDIV1 clock entry */ | |
/* Get PREDIV2 division factor and PLL2 multiplication factor */ | |
prediv2factor = ((RCC->CFGR2 & RCC_CFGR2_PREDIV2) >> 4) + 1; | |
pll2mull = ((RCC->CFGR2 & RCC_CFGR2_PLL2MUL) >> 8 ) + 2; | |
SystemCoreClock = (((HSE_VALUE / prediv2factor) * pll2mull) / prediv1factor) * pllmull; | |
} | |
} | |
#endif /* STM32F105xC */ | |
break; | |
default: | |
SystemCoreClock = HSI_VALUE; | |
break; | |
} | |
/* Compute HCLK clock frequency ----------------*/ | |
/* Get HCLK prescaler */ | |
tmp = AHBPrescTable[((RCC->CFGR & RCC_CFGR_HPRE) >> 4)]; | |
/* HCLK clock frequency */ | |
SystemCoreClock >>= tmp; | |
} | |
#if defined(STM32F100xE) || defined(STM32F101xE) || defined(STM32F101xG) || defined(STM32F103xE) || defined(STM32F103xG) | |
/** | |
* @brief Setup the external memory controller. Called in startup_stm32f1xx.s | |
* before jump to __main | |
* @param None | |
* @retval None | |
*/ | |
#ifdef DATA_IN_ExtSRAM | |
/** | |
* @brief Setup the external memory controller. | |
* Called in startup_stm32f1xx_xx.s/.c before jump to main. | |
* This function configures the external SRAM mounted on STM3210E-EVAL | |
* board (STM32 High density devices). This SRAM will be used as program | |
* data memory (including heap and stack). | |
* @param None | |
* @retval None | |
*/ | |
void SystemInit_ExtMemCtl(void) | |
{ | |
__IO uint32_t tmpreg; | |
/*!< FSMC Bank1 NOR/SRAM3 is used for the STM3210E-EVAL, if another Bank is | |
required, then adjust the Register Addresses */ | |
/* Enable FSMC clock */ | |
RCC->AHBENR = 0x00000114; | |
/* Delay after an RCC peripheral clock enabling */ | |
tmpreg = READ_BIT(RCC->AHBENR, RCC_AHBENR_FSMCEN); | |
/* Enable GPIOD, GPIOE, GPIOF and GPIOG clocks */ | |
RCC->APB2ENR = 0x000001E0; | |
/* Delay after an RCC peripheral clock enabling */ | |
tmpreg = READ_BIT(RCC->APB2ENR, RCC_APB2ENR_IOPDEN); | |
(void)(tmpreg); | |
/* --------------- SRAM Data lines, NOE and NWE configuration ---------------*/ | |
/*---------------- SRAM Address lines configuration -------------------------*/ | |
/*---------------- NOE and NWE configuration --------------------------------*/ | |
/*---------------- NE3 configuration ----------------------------------------*/ | |
/*---------------- NBL0, NBL1 configuration ---------------------------------*/ | |
GPIOD->CRL = 0x44BB44BB; | |
GPIOD->CRH = 0xBBBBBBBB; | |
GPIOE->CRL = 0xB44444BB; | |
GPIOE->CRH = 0xBBBBBBBB; | |
GPIOF->CRL = 0x44BBBBBB; | |
GPIOF->CRH = 0xBBBB4444; | |
GPIOG->CRL = 0x44BBBBBB; | |
GPIOG->CRH = 0x444B4B44; | |
/*---------------- FSMC Configuration ---------------------------------------*/ | |
/*---------------- Enable FSMC Bank1_SRAM Bank ------------------------------*/ | |
FSMC_Bank1->BTCR[4] = 0x00001091; | |
FSMC_Bank1->BTCR[5] = 0x00110212; | |
} | |
#endif /* DATA_IN_ExtSRAM */ | |
#endif /* STM32F100xE || STM32F101xE || STM32F101xG || STM32F103xE || STM32F103xG */ | |
/** | |
* @} | |
*/ | |
/** | |
* @} | |
*/ | |
/** | |
* @} | |
*/ | |
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/ |