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stm32F407------SPI

2022-07-25 17:12:00 【Can't go on the ground】

Catalog

One 、 The physical layer 、 Protocol layer

Two 、stm32 Of SPI peripherals

① The punctual atoms SPI Interface :(SPI1 identical )

② Wildfire SPI Interface :(SPI1 identical )

3、 ... and 、stm32 Of SPI Firmware library

① SPI_Direction

②SPI_Mode

③SPI_DataSize

④SPI_CPOL and SPI_CPHA

⑤SPI_NSS

⑥SPI_BaudRatePrescaler

⑦SPI_FirstBit

⑧SPI_CRCPolynomial

Four 、 Code ——SPI initialization

5、 ... and 、 Code —— Read FLASH Of ID

6、 ... and 、 Code —— Erase operation

7、 ... and 、 Code —— Read and write operations

8、 ... and 、 Code —— Routines and stored decimals

One 、 The physical layer 、 Protocol layer

CS = 0; Select film selection

full duplex

CPHA = 0; Odd edge sampling

CPHA = 1; Even edge sampling

Two 、stm32 Of SPI peripherals

① The punctual atoms SPI Interface :(SPI1 inequality )

② Wildfire SPI Interface :(SPI1 inequality )

3、 ... and 、stm32 Of SPI Firmware library

① SPI_Direction

This member setup SPI The direction of communication , Can be set to

Two wire full duplex (SPI_Direction_2Lines_FullDuplex),

Two lines only receive (SPI_Direction_2Lines_RxOnly),

One line only receives (SPI_Direction_1Line_Rx)、

Single line send only mode (SPI_Direction_1Line_Tx).

②SPI_Mode

This member setup SPI Working in host mode (SPI_Mode_Master) Or slave mode (SPI_Mode_Slave ),

The biggest difference between the two modes is SPI Of SCK The timing of the signal line ,SCK The time sequence of is generated by the host in the communication . If configured as slave mode ,STM32 Of SPI Peripherals will accept external SCK The signal .

③SPI_DataSize

This member may choose SPI The data frame size of communication is 8 position (SPI_DataSize_8b) still 16(SPI_DataSize_16b).

④SPI_CPOL and SPI_CPHA

These two member configurations SPI Of Clock polarity CPOL and Clock phase CPHA, These two configurations affect SPI Communication mode ,

Clock polarity CPOL member , Can be set to High level (SPI_CPOL_High) or Low level (SPI_CPOL_Low ).

Clock phase CPHA Can be set to SPI_CPHA_1Edge( stay SCK The odd edge of the data collection ) or SPI_CPHA_2Edge ( stay SCK Even edge of the data collection ) .

⑤SPI_NSS

This member configures NSS The mode of use of pins , You can choose Hardware mode (SPI_NSS_Hard ) And Software mode (SPI_NSS_Soft ), In hardware mode SPI The selection signal is from SPI The hardware automatically generates , The software model needs to put the corresponding GPIO When the port is set high or low, non chip select and chip select signals are generated . In practice, the application of software mode is more .

⑥SPI_BaudRatePrescaler

This member sets baud rate frequency division factor , The clock after frequency division is SPI Of SCK Clock frequency of signal line . This member parameter can be set to fpclk Of 2、4、6、8、16、32、64、128、256 frequency division .

⑦SPI_FirstBit

All serial communication protocols have MSB Go ahead ( The high data is at the top ) still LSB Go ahead ( The low data is in the front ) The problem of , and STM32 Of SPI Modules can be organized through this structure member , Program and control this feature .

⑧SPI_CRCPolynomial

This is a SPI Of CRC Polynomials in validation , If we use CRC When checking , Just use the parameters of this member ( polynomial ), To calculate CRC Value .

After configuring these structure members , To be called SPI_Init Function writes these parameters to the register , Realization SPI The initialization , And then call SPI_Cmd Enable SPI peripherals .

Four 、 Code ——SPI initialization

/* Private typedef -----------------------------------------------------------*/
//#define  sFLASH_ID                       0xEF3015     //W25X16
//#define  sFLASH_ID                       0xEF4015	    //W25Q16
//#define  sFLASH_ID                        0XEF4017     //W25Q64
#define  sFLASH_ID                       0XEF4018     //W25Q128


//#define SPI_FLASH_PageSize            4096
#define SPI_FLASH_PageSize              256
#define SPI_FLASH_PerWritePageSize      256

/* Private define ------------------------------------------------------------*/
/* Command definition - start *******************************/
#define W25X_WriteEnable		      0x06 
#define W25X_WriteDisable		      0x04 
#define W25X_ReadStatusReg		    0x05 
#define W25X_WriteStatusReg		  0x01 
#define W25X_ReadData			        0x03 
#define W25X_FastReadData		      0x0B 
#define W25X_FastReadDual		      0x3B 
#define W25X_PageProgram		      0x02 
#define W25X_BlockErase			      0xD8 
#define W25X_SectorErase		      0x20 
#define W25X_ChipErase			      0xC7 
#define W25X_PowerDown			      0xB9 
#define W25X_ReleasePowerDown	  0xAB 
#define W25X_DeviceID			        0xAB 
#define W25X_ManufactDeviceID   	0x90 
#define W25X_JedecDeviceID		    0x9F 

#define WIP_Flag                  0x01  /* Write In Progress (WIP) flag */
#define Dummy_Byte                0xFF
/* Command definition - ending *******************************/

/*SPI Interface definition - start ****************************/
#define FLASH_SPI                           SPI1
#define FLASH_SPI_CLK                       RCC_APB2Periph_SPI1
#define FLASH_SPI_CLK_INIT                  RCC_APB2PeriphClockCmd

#define FLASH_SPI_SCK_PIN                   GPIO_Pin_3                  
#define FLASH_SPI_SCK_GPIO_PORT             GPIOB                       
#define FLASH_SPI_SCK_GPIO_CLK              RCC_AHB1Periph_GPIOB
#define FLASH_SPI_SCK_PINSOURCE             GPIO_PinSource3
#define FLASH_SPI_SCK_AF                    GPIO_AF_SPI1

#define FLASH_SPI_MISO_PIN                  GPIO_Pin_4                
#define FLASH_SPI_MISO_GPIO_PORT            GPIOB                   
#define FLASH_SPI_MISO_GPIO_CLK             RCC_AHB1Periph_GPIOB
#define FLASH_SPI_MISO_PINSOURCE            GPIO_PinSource4
#define FLASH_SPI_MISO_AF                   GPIO_AF_SPI1

#define FLASH_SPI_MOSI_PIN                  GPIO_Pin_5                
#define FLASH_SPI_MOSI_GPIO_PORT            GPIOB                     
#define FLASH_SPI_MOSI_GPIO_CLK             RCC_AHB1Periph_GPIOB
#define FLASH_SPI_MOSI_PINSOURCE            GPIO_PinSource5
#define FLASH_SPI_MOSI_AF                   GPIO_AF_SPI1

#define FLASH_CS_PIN                        GPIO_Pin_6               
#define FLASH_CS_GPIO_PORT                  GPIOG                     
#define FLASH_CS_GPIO_CLK                   RCC_AHB1Periph_GPIOG// Software simulation mode 

#define SPI_FLASH_CS_LOW()      {FLASH_CS_GPIO_PORT->BSRRH=FLASH_CS_PIN;}
#define SPI_FLASH_CS_HIGH()     {FLASH_CS_GPIO_PORT->BSRRL=FLASH_CS_PIN;}
/*SPI Interface definition - ending ****************************/

void SPI_FLASH_Init(void)
{
  SPI_InitTypeDef  SPI_InitStructure;
  GPIO_InitTypeDef GPIO_InitStructure;
  
  /*  Can make  FLASH_SPI  And GPIO  The clock  */
  /*!< SPI_FLASH_SPI_CS_GPIO, SPI_FLASH_SPI_MOSI_GPIO, 
       SPI_FLASH_SPI_MISO_GPIO,SPI_FLASH_SPI_SCK_GPIO  Clock enable  */
  RCC_AHB1PeriphClockCmd (FLASH_SPI_SCK_GPIO_CLK | FLASH_SPI_MISO_GPIO_CLK|FLASH_SPI_MOSI_GPIO_CLK|FLASH_CS_GPIO_CLK, ENABLE);

  /*!< SPI_FLASH_SPI  Clock enable  */
  FLASH_SPI_CLK_INIT(FLASH_SPI_CLK, ENABLE);
 
  // Set pin multiplexing 
  GPIO_PinAFConfig(FLASH_SPI_SCK_GPIO_PORT,FLASH_SPI_SCK_PINSOURCE,FLASH_SPI_SCK_AF); 
	GPIO_PinAFConfig(FLASH_SPI_MISO_GPIO_PORT,FLASH_SPI_MISO_PINSOURCE,FLASH_SPI_MISO_AF); 
	GPIO_PinAFConfig(FLASH_SPI_MOSI_GPIO_PORT,FLASH_SPI_MOSI_PINSOURCE,FLASH_SPI_MOSI_AF); 
  
  /*!<  To configure  SPI_FLASH_SPI  Pin : SCK */
  GPIO_InitStructure.GPIO_Pin = FLASH_SPI_SCK_PIN;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;  
  
  GPIO_Init(FLASH_SPI_SCK_GPIO_PORT, &GPIO_InitStructure);
  
	/*!<  To configure  SPI_FLASH_SPI  Pin : MISO */
  GPIO_InitStructure.GPIO_Pin = FLASH_SPI_MISO_PIN;
  GPIO_Init(FLASH_SPI_MISO_GPIO_PORT, &GPIO_InitStructure);
  
	/*!<  To configure  SPI_FLASH_SPI  Pin : MOSI */
  GPIO_InitStructure.GPIO_Pin = FLASH_SPI_MOSI_PIN;
  GPIO_Init(FLASH_SPI_MOSI_GPIO_PORT, &GPIO_InitStructure);  

	/*!<  To configure  SPI_FLASH_SPI  Pin : CS */
  GPIO_InitStructure.GPIO_Pin = FLASH_CS_PIN;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
  GPIO_Init(FLASH_CS_GPIO_PORT, &GPIO_InitStructure);

  /*  Stop signal  FLASH: CS Pin high level */
  SPI_FLASH_CS_HIGH();

  /* FLASH_SPI  Mode configuration  */
  // FLASH chip   Support SPI Pattern 0 And mode 3, Set it accordingly CPOL CPHA
  SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
  SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
  SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
  SPI_InitStructure.SPI_CPOL = SPI_CPOL_High;
  SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;
  SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
  SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_2;
  SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
  SPI_InitStructure.SPI_CRCPolynomial = 7;
  SPI_Init(FLASH_SPI, &SPI_InitStructure);

  /*  Can make  FLASH_SPI  */
  SPI_Cmd(FLASH_SPI, ENABLE);
}

5、 ... and 、 Code —— Read FLASH Of ID

spi_flash.c：

 /**
  * @brief   Read FLASH ID
  * @param 	 nothing 
  * @retval FLASH ID
  */
u32 SPI_FLASH_ReadID(void)
{
  u32 Temp = 0, Temp0 = 0, Temp1 = 0, Temp2 = 0;

  /*  Start communicating ：CS Low level  */
  SPI_FLASH_CS_LOW();

  /*  send out JEDEC Instructions , Read ID */
  SPI_FLASH_SendByte(W25X_JedecDeviceID);

  /*  Read a byte of data  */
  Temp0 = SPI_FLASH_SendByte(Dummy_Byte);

  /*  Read a byte of data  */
  Temp1 = SPI_FLASH_SendByte(Dummy_Byte);

  /*  Read a byte of data  */
  Temp2 = SPI_FLASH_SendByte(Dummy_Byte);

  /*  Stop communicating ：CS High level  */
  SPI_FLASH_CS_HIGH();

	/* Put the data together , As the return value of the function */
  Temp = (Temp0 << 16) | (Temp1 << 8) | Temp2;

  return Temp;
}

 /**
  * @brief   Read FLASH Device ID
  * @param 	 nothing 
  * @retval FLASH Device ID
  */
u32 SPI_FLASH_ReadDeviceID(void)
{
  u32 Temp = 0;

  /* Select the FLASH: Chip Select low */
  SPI_FLASH_CS_LOW();

  /* Send "RDID " instruction */
  SPI_FLASH_SendByte(W25X_DeviceID);
  SPI_FLASH_SendByte(Dummy_Byte);
  SPI_FLASH_SendByte(Dummy_Byte);
  SPI_FLASH_SendByte(Dummy_Byte);
  
  /* Read a byte from the FLASH */
  Temp = SPI_FLASH_SendByte(Dummy_Byte);

  /* Deselect the FLASH: Chip Select high */
  SPI_FLASH_CS_HIGH();

  return Temp;
}

main.c：

/* 16M Serial flash W25Q128 initialization  */
	SPI_FLASH_Init();
	
	/*  obtain  Flash Device ID */
	DeviceID = SPI_FLASH_ReadDeviceID();
	
	Delay( 200 );
	
	/*  obtain  SPI Flash ID */
	FlashID = SPI_FLASH_ReadID();
	
	printf("\r\nFlashID is 0x%X,  Manufacturer Device ID is 0x%X\r\n", FlashID, DeviceID);

6、 ... and 、 Code —— Erase operation

/**
  * @brief   erase FLASH A sector 
  * @param  SectorAddr： Address of the sector to be erased 
  * @retval  nothing 
  */
void SPI_FLASH_SectorErase(u32 SectorAddr)
{
  /*  send out FLASH Write enabling commands  */
  SPI_FLASH_WriteEnable();
  SPI_FLASH_WaitForWriteEnd();
  /*  Erase sectors  */
  /*  choice FLASH: CS Low level  */
  SPI_FLASH_CS_LOW();
  /*  Send sector erase command */
  SPI_FLASH_SendByte(W25X_SectorErase);
  /* Send the high bit of the erase sector address */
  SPI_FLASH_SendByte((SectorAddr & 0xFF0000) >> 16);
  /*  Send the median of the erase sector address  */
  SPI_FLASH_SendByte((SectorAddr & 0xFF00) >> 8);
  /*  Send the low order of the erase sector address  */
  SPI_FLASH_SendByte(SectorAddr & 0xFF);
  /*  Stop signal  FLASH: CS  High level  */
  SPI_FLASH_CS_HIGH();
  /*  Wait until the erase is complete */
  SPI_FLASH_WaitForWriteEnd();
}


 /**
  * @brief   erase FLASH A sector , Erase the whole piece 
  * @param   nothing 
  * @retval  nothing 
  */
void SPI_FLASH_BulkErase(void)
{
  /*  send out FLASH Write enabling commands  */
  SPI_FLASH_WriteEnable();

  /*  Whole block  Erase */
  /*  choice FLASH: CS Low level  */
  SPI_FLASH_CS_LOW();
  /*  Send a block erase instruction */
  SPI_FLASH_SendByte(W25X_ChipErase);
  /*  Stop signal  FLASH: CS  High level  */
  SPI_FLASH_CS_HIGH();

  /*  Wait until the erase is complete */
  SPI_FLASH_WaitForWriteEnd();
}