STM32使用FSMC控制sram例程

一、基本概念

1. 与非总线复用的16位SRAM接口
FSMC配置
SRAM存储器和NOR闪存存储器共用相同的FSMC存储块，所用的协议依不同的存储器类型而有所不同。
控制SRAM存储器，FSMC应该具有下述功能：
●
使用或禁止地址/数据总线的复用功能。
●
选择所用的存储器类型：NOR闪存、SRAM或PSRAM。
●
定义外部存储器的数据总线宽度：8或16位。
●
使用或关闭扩展模式：扩展模式用于访问那些具有不同读写操作时序的存储器。
正如配置NOR闪存存储器一样，用户必须按照SRAM存储器的数据手册给出的时序数据，计算和设置下列参数：
●
ADDSET：地址建立时间
●
ADDHOLD：地址保持时间
●
DATAST：数据建立时间

二、例程

1. FSMC_SRAM.C

/******************** (C) COPYRIGHT 2008 STMicroelectronics ********************
* File Name          : fsmc_sram.c
* Author             : MCD Application Team
* Version            : V2.0.1
* Date               : 06/13/2008
* Description        : This file provides a set of functions needed to drive the 
*                      IS61WV51216BLL SRAM memory mounted on STM3210E-EVAL board.
********************************************************************************
* 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 "fsmc_sram.h"

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define Bank1_SRAM3_ADDR    ((u32)0x68000000)

#define SRAM_WRITE(Address, Data)  (*(vu16 *)(Address) = (Data))

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/

/*******************************************************************************
* Function Name  : FSMC_SRAM_Init
* Description    : Configures the FSMC and GPIOs to interface with the SRAM memory.
*                  This function must be called before any write/read operation
*                  on the SRAM.
* Input          : None 
* Output         : None
* Return         : None
*******************************************************************************/
void FSMC_SRAM_Init(void)
{
  FSMC_NORSRAMInitTypeDef  FSMC_NORSRAMInitStructure;
  FSMC_NORSRAMTimingInitTypeDef  p;
  GPIO_InitTypeDef GPIO_InitStructure; 
  
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOD | RCC_APB2Periph_GPIOG | RCC_APB2Periph_GPIOE |
                         RCC_APB2Periph_GPIOF, ENABLE);
  
/*-- GPIO Configuration ------------------------------------------------------*/
  /* SRAM Data lines configuration */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_8 | GPIO_Pin_9 |
                                GPIO_Pin_10 | GPIO_Pin_14 | GPIO_Pin_15;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(GPIOD, &GPIO_InitStructure); 
  
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7 | GPIO_Pin_8 | GPIO_Pin_9 | GPIO_Pin_10 |
                                GPIO_Pin_11 | GPIO_Pin_12 | GPIO_Pin_13 | GPIO_Pin_14 |
                                GPIO_Pin_15;
  GPIO_Init(GPIOE, &GPIO_InitStructure);
  
  /* SRAM Address lines configuration */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3 |
                                GPIO_Pin_4 | GPIO_Pin_5 | GPIO_Pin_12 | GPIO_Pin_13 |
                                GPIO_Pin_14 | GPIO_Pin_15;
  GPIO_Init(GPIOF, &GPIO_InitStructure);
  
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3 |
                                GPIO_Pin_4 | GPIO_Pin_5;
  GPIO_Init(GPIOG, &GPIO_InitStructure);
  
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11 | GPIO_Pin_12 | GPIO_Pin_13; 
  GPIO_Init(GPIOD, &GPIO_InitStructure);
   
  /* NOE and NWE configuration */  
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4 |GPIO_Pin_5;
  GPIO_Init(GPIOD, &GPIO_InitStructure);
  
  /* NE3 configuration */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10; 
  GPIO_Init(GPIOG, &GPIO_InitStructure);
  
  /* NBL0, NBL1 configuration */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1; 
  GPIO_Init(GPIOE, &GPIO_InitStructure); 
  
/*-- FSMC Configuration ------------------------------------------------------*/
  p.FSMC_AddressSetupTime = 0;
  p.FSMC_AddressHoldTime = 0;
  p.FSMC_DataSetupTime = 2;
  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_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_AsyncWait = FSMC_AsyncWait_Disable;
  FSMC_NORSRAMInitStructure.FSMC_WriteBurst = FSMC_WriteBurst_Disable;
  FSMC_NORSRAMInitStructure.FSMC_ReadWriteTimingStruct = &p;
  FSMC_NORSRAMInitStructure.FSMC_WriteTimingStruct = &p;

  FSMC_NORSRAMInit(&FSMC_NORSRAMInitStructure);

  /* Enable FSMC Bank1_SRAM Bank */
  FSMC_NORSRAMCmd(FSMC_Bank1_NORSRAM3, ENABLE);  
}

/*******************************************************************************
* Function Name  : FSMC_SRAM_WriteBuffer
* Description    : Writes a Half-word buffer to the FSMC SRAM memory. 
* Input          : - pBuffer : pointer to buffer. 
*                  - WriteAddr : SRAM memory internal address from which the data
*                    will be written.
*                  - NumHalfwordToWrite : number of half-words to write. 
*                    
* Output         : None
* Return         : None
*******************************************************************************/
void FSMC_SRAM_WriteBuffer(u16* pBuffer, u32 WriteAddr, u32 NumHalfwordToWrite)
{
  for(; NumHalfwordToWrite != 0; NumHalfwordToWrite--) /* while there is data to write */
  {
    /* Transfer data to the memory */
    *(u16 *) (Bank1_SRAM3_ADDR + WriteAddr) = *pBuffer++;
    
    /* Increment the address*/  
    WriteAddr += 2;
  }   
}

/*******************************************************************************
* Function Name  : FSMC_SRAM_ReadBuffer
* Description    : Reads a block of data from the FSMC SRAM memory.
* Input          : - pBuffer : pointer to the buffer that receives the data read 
*                    from the SRAM memory.
*                  - ReadAddr : SRAM memory internal address to read from.
*                  - NumHalfwordToRead : number of half-words to read.
* Output         : None
* Return         : None
*******************************************************************************/
void FSMC_SRAM_ReadBuffer(u16* pBuffer, u32 ReadAddr, u32 NumHalfwordToRead)
{
  for(; NumHalfwordToRead != 0; NumHalfwordToRead--) /* while there is data to read */
  {
    /* Read a half-word from the memory */
    *pBuffer++ = *(vu16*) (Bank1_SRAM3_ADDR + ReadAddr);

    /* Increment the address*/  
    ReadAddr += 2;
  }  
}

/******************* (C) COPYRIGHT 2008 STMicroelectronics *****END OF FILE****/

/***************************************************************
* Function Name  : FSMC_SRAM_WriteHalfWord
* Description    : Writes a half-word to the SRAM memory. 
* Input          : - WriteAddr : SRAM memory internal address to write to.
*                  - Data : Data to write. 
* Output         : None
* Return         : 
*******************************************************************************/
void FSMC_SRAM_WriteHalfWord(u32 WriteAddr, u16 Data)
{
  //NOR_WRITE(ADDR_SHIFT(0x05555), 0x00AA);
 // NOR_WRITE(ADDR_SHIFT(0x02AAA), 0x0055);
 // NOR_WRITE(ADDR_SHIFT(0x05555), 0x00A0);
  SRAM_WRITE((Bank1_SRAM3_ADDR + WriteAddr), Data);

  //return (FSMC_NOR_GetStatus(Program_Timeout));
}

/******************************************************************************
* Function Name  : FSMC_SRAM_ReadHalfWord
* Description    : Reads a half-word from the SRAM memory. 
* Input          : - ReadAddr : NOR memory internal address to read from.
* Output         : None
* Return         : Half-word read from the SRAM memory
*******************************************************************************/
u16 FSMC_SRAM_ReadHalfWord(u32 ReadAddr)
{
  //NOR_WRITE(ADDR_SHIFT(0x005555), 0x00AA); 
  //NOR_WRITE(ADDR_SHIFT(0x002AAA), 0x0055);  
  //NOR_WRITE((Bank1_NOR2_ADDR + ReadAddr), 0x00F0 );

  return (*(vu16 *)((Bank1_SRAM3_ADDR + ReadAddr)));
}
 

2.MAIN.C

/******************** (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 "fsmc_sram.h"

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define BUFFER_SIZE        0x400
#define WRITE_READ_ADDR    0x8000

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
GPIO_InitTypeDef GPIO_InitStructure;
ErrorStatus HSEStartUpStatus;

u16 TxBuffer[BUFFER_SIZE];
u16 RxBuffer[BUFFER_SIZE];
u32 WriteReadStatus = 0, Index = 0;

/* Private function prototypes -----------------------------------------------*/
void RCC_Configuration(void);
void NVIC_Configuration(void);
void Fill_Buffer(u16 *pBuffer, u16 BufferLenght, u32 Offset);

/* Private functions ---------------------------------------------------------*/
/*******************************************************************************
* Function Name  : main
* Description    : Main program.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
int main(void)
{
#ifdef DEBUG
  debug();
#endif

  /* System Clocks Configuration */
  RCC_Configuration();  

  /* NVIC Configuration */
  NVIC_Configuration();

  /* PF.06 and PF.07 config to drive LD1 and LD2 ******************************/
  /* Enable GPIOF clock */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOF, ENABLE);
  
  /* Configure PF.06 and PF.07 as Output push-pull */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(GPIOF, &GPIO_InitStructure);
  
  /* Write/read to/from FSMC SRAM memory  *************************************/
  /* Enable the FSMC Clock */
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_FSMC, ENABLE);
  
  /* Configure FSMC Bank1 NOR/SRAM3 */
  FSMC_SRAM_Init();

  /* Write data to FSMC SRAM memory */
  /* Fill the buffer to send */
  Fill_Buffer(TxBuffer, BUFFER_SIZE, 0x3212);
  FSMC_SRAM_WriteBuffer(TxBuffer, WRITE_READ_ADDR, BUFFER_SIZE);

  /* Read data from FSMC SRAM memory */
  FSMC_SRAM_ReadBuffer(RxBuffer, WRITE_READ_ADDR, BUFFER_SIZE); 

  /* Read back SRAM memory and check content correctness */   
  for (Index = 0x00; (Index < BUFFER_SIZE) && (WriteReadStatus == 0); Index++)
  {
    if (RxBuffer[Index] != TxBuffer[Index])
    {
      WriteReadStatus = Index + 1;
    }
  } 

  if (WriteReadStatus == 0)
  { /* OK */
    /* Turn on LD1 */
    GPIO_SetBits(GPIOF, GPIO_Pin_6);
  }
  else
  { /* KO */
    /* Turn off LD2 */
    GPIO_SetBits(GPIOF, GPIO_Pin_7);     
  }

  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 2 wait state */
    FLASH_SetLatency(FLASH_Latency_2);
  
    /* HCLK = SYSCLK */
    RCC_HCLKConfig(RCC_SYSCLK_Div1); 
  
    /* PCLK2 = HCLK */
    RCC_PCLK2Config(RCC_HCLK_Div1);

    /* PCLK1 = HCLK/2 */
    RCC_PCLK1Config(RCC_HCLK_Div2);

    /* PLLCLK = 8MHz * 9 = 72 MHz */
    RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9);

    /* Enable PLL */ 
    RCC_PLLCmd(ENABLE);

    /* Wait till PLL is ready */
    while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET)
    {
    }

    /* Select PLL as system clock source */
    RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);

    /* Wait till PLL is used as system clock source */
    while(RCC_GetSYSCLKSource() != 0x08)
    {
    }
  }
}

/*******************************************************************************
* Function Name  : NVIC_Configuration
* Description    : Configures 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
}

/*******************************************************************************
* Function name : Fill_Buffer
* Description   : Fill the global buffer
* Input         : - pBuffer: pointer on the Buffer to fill
*                 - BufferSize: size of the buffer to fill
*                 - Offset: first value to fill on the Buffer
* Output param  : None
*******************************************************************************/
void Fill_Buffer(u16 *pBuffer, u16 BufferLenght, u32 Offset)
{
  u16 IndexTmp = 0;

  /* Put in global buffer same values */
  for (IndexTmp = 0; IndexTmp < BufferLenght; IndexTmp++ )
  {
    pBuffer[IndexTmp] = IndexTmp + Offset;
  }
}

#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