stm32 使用FSMC连接bank1的第三个存储区程序参考及说明

include “sram.h”

//////////////////////////////////////////////////////////////////////////////////

//使用NOR/SRAM的 Bank1.sector3,地址位HADDR[27,26]=10

//对IS61LV25616/IS62WV25616,地址线范围为A0~A17

//对IS61LV51216/IS62WV51216,地址线范围为A0~A18

define Bank1_SRAM3_ADDR ((u32)(0x68000000))

//初始化外部SRAM

void FSMC_SRAM_Init(void)

{

FSMC_NORSRAMInitTypeDef FSMC_NORSRAMInitStructure;

FSMC_NORSRAMTimingInitTypeDef readWriteTiming;

GPIO_InitTypeDef GPIO_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOD|RCC_APB2Periph_GPIOE|RCC_APB2Periph_GPIOF|RCC_APB2Periph_GPIOG,ENABLE);
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_FSMC,ENABLE);

GPIO_InitStructure.GPIO_Pin = 0xFF33;               //PORTD复用推挽输出  1111 1111 0011 0011
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;          //复用推挽输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOD, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = 0xFF83;               //PORTE复用推挽输出 1111 1111 1000 0011
GPIO_Init(GPIOE, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = 0xF03F;               //PORTD复用推挽输出 1111 0000 0011 1111
GPIO_Init(GPIOF, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = 0x043F;               //PORTD复用推挽输出 0000 0100 0011 1111
GPIO_Init(GPIOG, &GPIO_InitStructure);

readWriteTiming.FSMC_AddressSetupTime = 0x00;    //地址建立时间（ADDSET）为1个HCLK 1/36M=27ns
readWriteTiming.FSMC_AddressHoldTime = 0x00;     //地址保持时间（ADDHLD）模式A未用到
readWriteTiming.FSMC_DataSetupTime = 0x03;       //数据保持时间（DATAST）为3个HCLK 4/72M=55ns(对EM的SRAM芯片)
readWriteTiming.FSMC_BusTurnAroundDuration = 0x00;
readWriteTiming.FSMC_CLKDivision = 0x00;
readWriteTiming.FSMC_DataLatency = 0x00;            //数据产生时间
readWriteTiming.FSMC_AccessMode = FSMC_AccessMode_A;     //模式A 操作时序

FSMC_NORSRAMInitStructure.FSMC_Bank = FSMC_Bank1_NORSRAM3;            //  这里我们使用NE3 ，也就对应BTCR[4],[5]。
FSMC_NORSRAMInitStructure.FSMC_DataAddressMux = FSMC_DataAddressMux_Disable;      //地址数据不复用
FSMC_NORSRAMInitStructure.FSMC_MemoryType =FSMC_MemoryType_SRAM;           //   FSMC_MemoryType_SRAM存储器类型为SRAM
FSMC_NORSRAMInitStructure.FSMC_MemoryDataWidth = FSMC_MemoryDataWidth_16b;     //存储器数据宽度为16bit
FSMC_NORSRAMInitStructure.FSMC_BurstAccessMode =FSMC_BurstAccessMode_Disable;     // 关闭突发模式访问
FSMC_NORSRAMInitStructure.FSMC_WaitSignalPolarity = FSMC_WaitSignalPolarity_Low;  //等待信号优先级，只有在使能突发访问模式才有效
FSMC_NORSRAMInitStructure.FSMC_AsynchronousWait=FSMC_AsynchronousWait_Disable;
FSMC_NORSRAMInitStructure.FSMC_WrapMode = FSMC_WrapMode_Disable;              //关闭Wrapped burst access mode，只有在使能突发访问模式才有效
FSMC_NORSRAMInitStructure.FSMC_WaitSignalActive = FSMC_WaitSignalActive_BeforeWaitState;    //等待信号设置，只有在使能突发访问模式才有效
FSMC_NORSRAMInitStructure.FSMC_WriteOperation = FSMC_WriteOperation_Enable;         //存储器写使能
FSMC_NORSRAMInitStructure.FSMC_WaitSignal = FSMC_WaitSignal_Disable;                   //使能/关闭等待信息设置，只在使能突发访问模式才有效
FSMC_NORSRAMInitStructure.FSMC_ExtendedMode = FSMC_ExtendedMode_Disable; // 读写使用相同的时序
FSMC_NORSRAMInitStructure.FSMC_WriteBurst = FSMC_WriteBurst_Disable;
FSMC_NORSRAMInitStructure.FSMC_ReadWriteTimingStruct = &readWriteTiming; //读写操作时序参数
FSMC_NORSRAMInitStructure.FSMC_WriteTimingStruct = &readWriteTiming; //读写同样时序

FSMC_NORSRAMInit(&FSMC_NORSRAMInitStructure);  //初始化FSMC配置

FSMC_NORSRAMCmd(FSMC_Bank1_NORSRAM3, ENABLE);  // 使能BANK3

}

//在指定地址开始,连续写入n个字节.

//pBuffer:字节指针

//WriteAddr:要写入的地址

//n:要写入的字节数

void FSMC_SRAM_WriteBuffer(u8* pBuffer,u32 WriteAddr,u32 n)

{

for(;n!=0;n–)

{

(vu8)(Bank1_SRAM3_ADDR+WriteAddr)=*pBuffer;

WriteAddr++;

pBuffer++;

}

}

//在指定地址开始,连续读出n个字节.

//pBuffer:字节指针

//ReadAddr:要读出的起始地址

//n:要写入的字节数

void FSMC_SRAM_ReadBuffer(u8* pBuffer,u32 ReadAddr,u32 n)

{

for(;n!=0;n–)

{

pBuffer++=(vu8*)(Bank1_SRAM3_ADDR+ReadAddr);

ReadAddr++;

}

}

////////////////////////////////////////////////////////////////////////////////////////

//测试函数

//在指定地址写入1个字节

//addr:地址

//data:要写入的数据

void fsmc_sram_test_write(u8 data,u32 addr)

{

FSMC_SRAM_WriteBuffer(&data,addr,1);//写入1个字节

}

//读取1个字节

//addr:要读取的地址

//返回值:读取到的数据

u8 fsmc_sram_test_read(u32 addr)

{

u8 data;

FSMC_SRAM_ReadBuffer(&data,addr,1);

return data;

}