硬件为stm32+m25p40
void SPIx_Init(void) //spi2初始化
{
SPI_InitTypeDef SPI_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOB, ENABLE );
RCC_APB1PeriphClockCmd( RCC_APB1Periph_SPI2, ENABLE );
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_Init(GPIOB, &GPIO_InitStructure); //NSS PB12
/* Deselect the FLASH: Chip Select high */
SPI_FLASH_CS_HIGH();
/* SPI2 configuration */
SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex; //SPI 设置为双线双向全双工
SPI_InitStructure.SPI_Mode = SPI_Mode_Master; //设置为主SPI
SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b; //SPI 发送接收8 位帧结构
SPI_InitStructure.SPI_CPOL = SPI_CPOL_High; //时钟悬空高
SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge; //数据捕获于第二个时钟沿
SPI_InitStructure.SPI_NSS = SPI_NSS_Soft; //内部NSS 信号有SSI 位控制
SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_64;//波特率预分频值为64
SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB; //数据传输从MSB位开始
SPI_InitStructure.SPI_CRCPolynomial = 7;
SPI_Init(SPI2, &SPI_InitStructure);
/* Enable SPI1 */
SPI_Cmd(SPI2, ENABLE); //使能SPI 外设
}
u8 DuumyClock[4] = {0xA5,0xA5,0xA5,0xA5};
void SPI_FLASH_BufferRead(u8* pBuffer, u32 ReadAddr, u16 NumByteToRead)
{
DMA_InitTypeDef DMA_InitStructure;
//配置DMA通道
DMA_DeInit(DMA1_Channel4);
DMA_DeInit(DMA1_Channel5);
DMA_InitStructure.DMA_PeripheralBaseAddr = (u32)&SPI2->DR;
DMA_InitStructure.DMA_MemoryBaseAddr = (u32)pBuffer;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStructure.DMA_BufferSize = NumByteToRead;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;
DMA_InitStructure.DMA_Priority = DMA_Priority_VeryHigh;
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA1_Channel4, &DMA_InitStructure);
DMA_InitStructure.DMA_MemoryBaseAddr = (u32)DuumyClock; //dummy
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
DMA_InitStructure.DMA_Priority = DMA_Priority_Low;
DMA_Init(DMA1_Channel5, &DMA_InitStructure);
SPI_I2S_DMACmd(SPI2, SPI_I2S_DMAReq_Tx, ENABLE);
SPI_I2S_DMACmd(SPI2, SPI_I2S_DMAReq_Rx, ENABLE);
SPI_FLASH_StartReadSequence(ReadAddr); //发送开始读命令与地址
DMA_Cmd(DMA1_Channel4,ENABLE);
DMA_Cmd(DMA1_Channel5,ENABLE);
while(!DMA_GetFlagStatus(DMA1_FLAG_TC4)) ;
while(!DMA_GetFlagStatus(DMA1_FLAG_TC5)) ;
DMA_Cmd(DMA1_Channel4, DISABLE);
DMA_Cmd(DMA1_Channel5, DISABLE);
SPI_FLASH_CS_HIGH();
SPI_FLASH_SendByte(Dummy_Byte) ；
}
u8 SPI_FLASH_SendByte(u8 byte)
{
u16 count = 0;//
/* Loop while DR register in not emplty */
while (SPI_I2S_GetFlagStatus(SPI2, SPI_I2S_FLAG_TXE) == RESET)
{
count++;
if (count > 65533)
{
return 0;
}
}
/* Send byte through the SPI1 peripheral */
SPI_I2S_SendData(SPI2, byte);
/* Wait to receive a byte */
count = 0;
while (SPI_I2S_GetFlagStatus(SPI2, SPI_I2S_FLAG_RXNE) == RESET)
{
count++;
if (count > 65533)
{
return 0;
}
}
/* Return the byte read from the SPI bus */
return SPI_I2S_ReceiveData(SPI2);
}
u8 SPI_FLASH_ReadByte(void)
{
return (SPI_FLASH_SendByte(Dummy_Byte));
}
void SPI_FLASH_StartReadSequence(u32 ReadAddr)
{
/* Select the FLASH: Chip Select low */
SPI_FLASH_CS_LOW();
/* Send "Read from Memory " instruction */
SPI_FLASH_SendByte(READ);
/* Send the 24-bit address of the address to read from -----------------------*/
/* Send ReadAddr high nibble address byte */
SPI_FLASH_SendByte((ReadAddr & 0xFF0000) >> 16);
/* Send ReadAddr medium nibble address byte */
SPI_FLASH_SendByte((ReadAddr& 0xFF00) >> 8);
/* Send ReadAddr low nibble address byte */
SPI_FLASH_SendByte(ReadAddr & 0xFF);
}
/*******************************************************************************
* Function Name : SPI_FLASH_SectorErase
* Description : Erases the specified FLASH sector.
* Input : SectorAddr: address of the sector to erase.
* Output : None
* Return : None
*******************************************************************************/
void SPI_FLASH_SectorErase(u32 SectorAddr)
{
/* Send write enable instruction */
SPI_FLASH_WriteEnable();
/* Sector Erase */
/* Select the FLASH: Chip Select low */
SPI_FLASH_CS_LOW();
/* Send Sector Erase instruction */
SPI_FLASH_SendByte(SE);
/* Send SectorAddr high nibble address byte */
SPI_FLASH_SendByte((SectorAddr & 0xFF0000) >> 16);
/* Send SectorAddr medium nibble address byte */
SPI_FLASH_SendByte((SectorAddr & 0xFF00) >> 8);
/* Send SectorAddr low nibble address byte */
SPI_FLASH_SendByte(SectorAddr & 0xFF);
/* Deselect the FLASH: Chip Select high */
SPI_FLASH_CS_HIGH();
/* Wait the end of Flash writing */
SPI_FLASH_WaitForWriteEnd();
}
/*******************************************************************************
* Function Name : SPI_FLASH_BulkErase
* Description : Erases the entire FLASH.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void SPI_FLASH_BulkErase(void)
{
/* Send write enable instruction */
SPI_FLASH_WriteEnable();
/* Bulk Erase */
/* Select the FLASH: Chip Select low */
SPI_FLASH_CS_LOW();
/* Send Bulk Erase instruction */
SPI_FLASH_SendByte(BE);
/* Deselect the FLASH: Chip Select high */
SPI_FLASH_CS_HIGH();
/* Wait the end of Flash writing */
SPI_FLASH_WaitForWriteEnd();
}
/*******************************************************************************
* Function Name : SPI_FLASH_PageWrite
* Description : Writes more than one byte to the FLASH with a single WRITE
* cycle(Page WRITE sequence). The number of byte can't exceed
* the FLASH page size.
* Input : - pBuffer : pointer to the buffer containing the data to be
* written to the FLASH.
* - WriteAddr : FLASH's internal address to write to.
* - NumByteToWrite : number of bytes to write to the FLASH,
* must be equal or less than "SPI_FLASH_PageSize" value.
* Output : None
* Return : None
*******************************************************************************/
void SPI_FLASH_PageWrite(u8* pBuffer, u32 WriteAddr, u16 NumByteToWrite)
{
/* Enable the write access to the FLASH */
SPI_FLASH_WriteEnable();
/* Select the FLASH: Chip Select low */
SPI_FLASH_CS_LOW();
/* Send "Write to Memory " instruction */
SPI_FLASH_SendByte(WRITE);
/* Send WriteAddr high nibble address byte to write to */
SPI_FLASH_SendByte((WriteAddr & 0xFF0000) >> 16);
/* Send WriteAddr medium nibble address byte to write to */
SPI_FLASH_SendByte((WriteAddr & 0xFF00) >> 8);
/* Send WriteAddr low nibble address byte to write to */
SPI_FLASH_SendByte(WriteAddr & 0xFF);
/* while there is data to be written on the FLASH */
while (NumByteToWrite--)
{
/* Send the current byte */
SPI_FLASH_SendByte(*pBuffer);
/* Point on the next byte to be written */
pBuffer++;
}
/* Deselect the FLASH: Chip Select high */
SPI_FLASH_CS_HIGH();
/* Wait the end of Flash writing */
SPI_FLASH_WaitForWriteEnd();
}
/*******************************************************************************
* Function Name : SPI_FLASH_BufferWrite
* Description : Writes block of data to the FLASH. In this function, the
* number of WRITE cycles are reduced, using Page WRITE sequence.
* Input : - pBuffer : pointer to the buffer containing the data to be
* written to the FLASH.
* - WriteAddr : FLASH's internal address to write to.
* - NumByteToWrite : number of bytes to write to the FLASH.
* Output : None
* Return : None
*******************************************************************************/
void SPI_FLASH_BufferWrite(u8* pBuffer, u32 WriteAddr, u16 NumByteToWrite)
{
u8 NumOfPage = 0, NumOfSingle = 0, Addr = 0, count = 0, temp = 0;
Addr = WriteAddr % SPI_FLASH_PageSize;
count = SPI_FLASH_PageSize - Addr;
NumOfPage = NumByteToWrite / SPI_FLASH_PageSize;
NumOfSingle = NumByteToWrite % SPI_FLASH_PageSize;
if (Addr == 0) /* WriteAddr is SPI_FLASH_PageSize aligned */
{
if (NumOfPage == 0) /* NumByteToWrite < SPI_FLASH_PageSize */
{
SPI_FLASH_PageWrite(pBuffer, WriteAddr, NumByteToWrite);
}
else /* NumByteToWrite > SPI_FLASH_PageSize */
{
while (NumOfPage--)
{
SPI_FLASH_PageWrite(pBuffer, WriteAddr, SPI_FLASH_PageSize);
WriteAddr += SPI_FLASH_PageSize;
pBuffer += SPI_FLASH_PageSize;
}
SPI_FLASH_PageWrite(pBuffer, WriteAddr, NumOfSingle);
}
}
else /* WriteAddr is not SPI_FLASH_PageSize aligned */
{
if (NumOfPage == 0) /* NumByteToWrite < SPI_FLASH_PageSize */
{
if (NumOfSingle > count) /* (NumByteToWrite + WriteAddr) > SPI_FLASH_PageSize */
{
temp = NumOfSingle - count;
SPI_FLASH_PageWrite(pBuffer, WriteAddr, count);
WriteAddr += count;
pBuffer += count;
SPI_FLASH_PageWrite(pBuffer, WriteAddr, temp);
}
else
{
SPI_FLASH_PageWrite(pBuffer, WriteAddr, NumByteToWrite);
}
}
else /* NumByteToWrite > SPI_FLASH_PageSize */
{
NumByteToWrite -= count;
NumOfPage = NumByteToWrite / SPI_FLASH_PageSize;
NumOfSingle = NumByteToWrite % SPI_FLASH_PageSize;
SPI_FLASH_PageWrite(pBuffer, WriteAddr, count);
WriteAddr += count;
pBuffer += count;
while (NumOfPage--)
{
SPI_FLASH_PageWrite(pBuffer, WriteAddr, SPI_FLASH_PageSize);
WriteAddr += SPI_FLASH_PageSize;
pBuffer += SPI_FLASH_PageSize;
}
if (NumOfSingle != 0)
{
SPI_FLASH_PageWrite(pBuffer, WriteAddr, NumOfSingle);
}
}
}
}
}
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