/**
******************************************************************************
* @file system_stm32l1xx.c
* @author MCD Application Team
* @brief CMSIS Cortex-M3 Device Peripheral Access Layer System Source File.
*
* This file provides two functions and one global variable to be called from
* user application:
* - SystemInit(): This function is called at startup just after reset and
* before branch to main program. This call is made inside
* the "startup_stm32l1xx.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.
*
******************************************************************************
* @attention
*
* <h2><center>© Copyright (c) 2017 STMicroelectronics.
* All rights reserved.</center></h2>
*
* This software component is licensed by ST under BSD 3-Clause license,
* 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/BSD-3-Clause
*
******************************************************************************
*/
/** @addtogroup CMSIS
* @{
*/
/** @addtogroup stm32l1xx_system
* @{
*/
/** @addtogroup STM32L1xx_System_Private_Includes
* @{
*/
#include "stm32l1xx.h"
/**
* @}
*/
/** @addtogroup STM32L1xx_System_Private_TypesDefinitions
* @{
*/
/**
* @}
*/
/** @addtogroup STM32L1xx_System_Private_Defines
* @{
*/
#if !defined (HSE_VALUE)
#define HSE_VALUE ((uint32_t)8000000U) /*!< 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)8000000U) /*!< 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 mounted
on STM32L152D_EVAL board as data memory */
/* #define DATA_IN_ExtSRAM */
/*!< Uncomment the following line if you need to relocate your vector Table in
Internal SRAM. */
/* #define VECT_TAB_SRAM */
#define VECT_TAB_OFFSET 0x00U /*!< Vector Table base offset field.
This value must be a multiple of 0x200. */
/**
* @}
*/
/** @addtogroup STM32L1xx_System_Private_Macros
* @{
*/
/**
* @}
*/
/** @addtogroup STM32L1xx_System_Private_Variables
* @{
*/
/* This variable is updated in three ways:
1) by calling CMSIS function SystemCoreClockUpdate()
2) by calling HAL API function HAL_RCC_GetHCLKFreq()
3) each time HAL_RCC_ClockConfig() is called to configure the system clock frequency
Note: If you use this function to configure the system clock; then there
is no need to call the 2 first functions listed above, since SystemCoreClock
variable is updated automatically.
*/
uint32_t SystemCoreClock = 2097000U;
const uint8_t PLLMulTable[9] = {3U, 4U, 6U, 8U, 12U, 16U, 24U, 32U, 48U};
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};
/**
* @}
*/
/** @addtogroup STM32L1xx_System_Private_FunctionPrototypes
* @{
*/
#if defined (STM32L151xD) || defined (STM32L152xD) || defined (STM32L162xD)
#ifdef DATA_IN_ExtSRAM
static void SystemInit_ExtMemCtl(void);
#endif /* DATA_IN_ExtSRAM */
#endif /* STM32L151xD || STM32L152xD || STM32L162xD */
/**
* @}
*/
/** @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)
{
#ifdef DATA_IN_ExtSRAM
SystemInit_ExtMemCtl();
#endif /* DATA_IN_ExtSRAM */
#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;
}
#if defined (STM32L151xD) || defined (STM32L152xD) || defined (STM32L162xD)
#ifdef DATA_IN_ExtSRAM
/**
* @brief Setup the external memory controller.
* Called in SystemInit() function before jump to main.
* This function configures the external SRAM mounted on STM32L152D_EVAL board
* 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 = 0;
/* Flash 1 wait state */
FLASH->ACR |= FLASH_ACR_LATENCY;
/* Power enable */
RCC->APB1ENR |= RCC_APB1ENR_PWREN;
/* Delay after an RCC peripheral clock enabling */
tmpreg = READ_BIT(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)
{
}
/*-- GPIOs Configuration -----------------------------------------------------*/
/*
+-------------------+--------------------+------------------+------------------+
+ SRAM pins assignment +
+-------------------+--------------------+------------------+------------------+
| PD0 <-> FSMC_D2 | PE0 <-> FSMC_NBL0 | PF0 <-> FSMC_A0 | PG0 <-> FSMC_A10 |
| PD1 <-> FSMC_D3 | PE1 <-> FSMC_NBL1 | PF1 <-> FSMC_A1 | PG1 <-> FSMC_A11 |
| PD4 <-> FSMC_NOE | PE7 <-> FSMC_D4 | PF2 <-> FSMC_A2 | PG2 <-> FSMC_A12 |
| PD5 <-> FSMC_NWE | PE8 <-> FSMC_D5 | PF3 <-> FSMC_A3 | PG3 <-> FSMC_A13 |
| PD8 <-> FSMC_D13 | PE9 <-> FSMC_D6 | PF4 <-> FSMC_A4 | PG4 <-> FSMC_A14 |
| PD9 <-> FSMC_D14 | PE10 <-> FSMC_D7 | PF5 <-> FSMC_A5 | PG5 <-> FSMC_A15 |
| PD10 <-> FSMC_D15 | PE11 <-> FSMC_D8 | PF12 <-> FSMC_A6 | PG10<-> FSMC_NE2 |
| PD11 <-> FSMC_A16 | PE12 <-> FSMC_D9 | PF13 <-> FSMC_A7 |------------------+
| PD12 <-> FSMC_A17 | PE13 <-> FSMC_D10 | PF14 <-> FSMC_A8 |
| PD13 <-> FSMC_A18 | PE14 <-> FSMC_D11 | PF15 <-> FSMC_A9 |
| PD14 <-> FSMC_D0 | PE15 <-> FSMC_D12 |------------------+
| PD15 <-> FSMC_D1 |--------------------+
+-------------------+
*/
/* Enable GPIOD, GPIOE, GPIOF and GPIOG interface clock */
RCC->AHBENR = 0x000080D8;
/* Delay after an RCC peripheral clock enabling */
tmpreg = READ_BIT(RCC->AHBENR, RCC_AHBENR_GPIODEN);
/* Connect PDx pins to FSMC Alternate function */
GPIOD->AFR[0] = 0x00CC00CC;
GPIOD->AFR[1] = 0xCCCCCCCC;
/* Configure PDx pins in Alternate function mode */
GPIOD->MODER = 0xAAAA0A0A;
/* Configure PDx pins speed to 40 MHz */
GPIOD->OSPEEDR = 0xFFFF0F0F;
/* Configure PDx pins Output type to push-pull */
GPIOD->OTYPER = 0x00000000;
/* No pull-up, pull-down for PDx pins */
GPIOD->PUPDR = 0x00000000;
/* Connect PEx pins to FSMC Alternate function */
GPIOE->AFR[0] = 0xC00000CC;
GPIOE->AFR[1] = 0xCCCCCCCC;
/* Configure PEx pins in Alternate function mode */
GPIOE->MODER = 0xAAAA800A;
/* Configure PEx pins speed to 40 MHz */
GPIOE->OSPEEDR = 0xFFFFC00F;
/* Configure PEx pins Output type to push-pull */
GPIOE->OTYPER = 0x00000000;
/* No pull-up, pull-down for PEx pins */
GPIOE->PUPDR = 0x00000000;
/* Connect PFx pins to FSMC Alternate function */
GPIOF->AFR[0] = 0x00CCCCCC;
GPIOF->AFR[1] = 0xCCCC0000;
/* Configure PFx pins in Alternate function mode */
GPIOF->MODER = 0xAA000AAA;
/* Configure PFx pins speed to 40 MHz */
GPIOF->OSPEEDR = 0xFF000FFF;
/* Configure PFx pins Output type to push-pull */
GPIOF->OTYPER = 0x00000000;
/* No pull-up, pull-down for PFx pins */
GPIOF->PUPDR = 0x00000000;
/* Connect PGx pins to FSMC Alternate function */
GPIOG->AFR[0] = 0x00CCCCCC;
GPIOG->AFR[1] = 0x00000C00;
/* Configure PGx pins in Alternate function mode */
GPIOG->MODER = 0x00200AAA;
/* Configure PGx pins speed to 40 MHz */
GPIOG->OSPEEDR = 0x00300FFF;
/* Configure PGx pins Output type to push-pull */
GPIOG->OTYPER = 0x00000000;
/* No pull-up, pull-down for PGx pins */
GPIOG->PUPDR = 0x00000000;
/*-- FSMC Configuration ------------------------------------------------------*/
/* Enable the FSMC interface clock */
RCC->AHBENR = 0x400080D8;
/* Delay after an RCC peripheral clock enabling */
tmpreg = READ_BIT(RCC->AHBENR, RCC_AHBENR_FSMCEN);
(void)(tmpreg);
/* Configure and enable Bank1_SRAM3 */
FSMC_Bank1->BTCR[4] = 0x00001011;
FSMC_Bank1->BTCR[5] = 0x00000300;
FSMC_Bank1E->BWTR[4] = 0x0FFFFFFF;
/*
Bank1_SRAM3 is configured as follow:
p.FSMC_AddressSetupTime = 0;
p.FSMC_AddressHoldTime = 0;
p.FSMC_DataSetupTime = 3;
p.FSMC_BusTurnAroundDuration = 0;
p.FSMC_CLKDivision = 0;
p.FSMC_DataLatency = 0;
p.FSMC_AccessMode = FSMC_AccessMode_A;
FSMC_NORSRAMInitStructure.FSMC_Bank = FSMC_Bank1_NORSRAM3;
FSMC_NORSRAMInitStructure.FSMC_DataAddressMux = FSMC_DataAddressMux_Disable;
FSMC_NORSRAMInitStructure.FSMC_MemoryType = FSMC_MemoryType_SRAM;
FSMC_NORSRAMInitStructure.FSMC_MemoryDataWidth = FSMC_MemoryDataWidth_16b;
FSMC_NORSRAMInitStructure.FSMC_BurstAccessMode = FSMC_BurstAccessMode_Disable;
FSMC_NORSRAMInitStructure.FSMC_AsynchronousWait = FSMC_AsynchronousWait_Disable;
FSMC_NORSRAMInitStructure.FSMC_WaitSignalPolarity = FSMC_WaitSignalPolarity_Low;
FSMC_NORSRAMInitStructure.FSMC_WrapMode = FSMC_WrapMode_Disable;
FSMC_NORSRAMInitStructure.FSMC_WaitSignalActive = FSMC_WaitSignalActive_BeforeWaitState;
FSMC_NORSRAMInitStructure.FSMC_WriteOperation = FSMC_WriteOperation_Enable;
FSMC_NORSRAMInitStructure.FSMC_WaitSignal = FSMC_WaitSignal_Disable;
FSMC_NORSRAMInitStructure.FSMC_ExtendedMode = FSMC_ExtendedMode_Disable;
FSMC_NORSRAMInitStructure.FSMC_WriteBurst = FSMC_WriteBurst_Disable;
FSMC_NORSRAMInitStructure.FSMC_ReadWriteTimingStruct = &p;
FSMC_NORSRAMInitStructure.FSMC_WriteTimingStruct = &p;
FSMC_NORSRAMInit(&FSMC_NORSRAMInitStructure);
FSMC_NORSRAMCmd(FSMC_Bank1_NORSRAM3, ENABLE);
*/
}
#endif /* DATA_IN_ExtSRAM */
#endif /* STM32L151xD || STM32L152xD || STM32L162xD */
/**
* @}
*/
/**
* @}
*/
/**
* @}
*/
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/