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第9章

SPI

9.1 STM32 SPI簡介

serial peripheral interface (SPI) 可以與外部週邊半/ 全雙工、同步、串列通信，SPI可設為master，並提供外部週邊通訊clock (SCK)，SPI也可以在多個master情況使用。

STM32F10x處理器SPI結構圖

 

 

通常SPI透過4個pin去連接外部週邊:

 

● MISO: Master In / Slave Out data. SPI設為master，此腳接收從slave傳來的資料，

 

         SPI設為slave，此腳傳送資料到master。

 

● MOSI: Master Out / Slave In data. SPI設為master，此腳傳送資料到slave，

 

         SPI設為slave，此腳接收從master傳來的資料。

 

● SCK: 由master提供clock輸出給slave當成通訊clock。.

 

● NSS: Slave select. 該腳可以被master當做要和那個slave做構通。

 

單個主從SPI置配

 

Slave select (NSS) pin management

STM32F10x提供2種NSS模式

● Software NSS mode: 透過SP1_CR1暫存器裡的SSM bit啟動此模式，外部的NSS腳就可做為其他用途使用，而內部NSS信號透過SP1_CR1暫存器SSI設置。

● Hardware NSS mode: 有二種配置

– NSS output is enabled: 透過SPI_CR2暫存器裡SSOE bit允許輸出，當NSS被拉低時，其他SPI配置為NSS模式，則會被當成slave，此清形只允許一個master存在。

– NSS output is disabled: 透過SPI_CR2暫存器裡SSOE bit禁止輸出，且可以允許多個master的配置。.

Figure 208. Hardware/software slave select management

 

 

9.2 SPI Standard Driver Library

本節說明ST提供SPI Standard Driver Library

Function name	Description
SPI_I2S_DeInit	Re-initializes the SPIx peripheral registers to their default reset values.
SPI_Init	Initializes the SPIx peripheral according to the specified parameters in the SPI_InitStruct.
SPI_StructInit	Fills each SPI_InitStruct member with its default value.
SPI_Cmd	Enables or disables the specified SPI peripheral.
SPI_I2S_ITConfig	Enables or disables the specified SPI/I2S interrupts.
SPI_I2S_DMACmd	Enables or disables the SPIx/I2Sx DMA interface.
SPI_I2S_SendData	Transmits data through the SPIx/I2Sx peripheral.
SPI_I2S_ReceiveData	Returns the most recent received data through the SPIx/I2Sx peripheral.
SPI_NSSInternalSoftwareConfig	Configures internally by software the NSS pin for the selected SPI.
SPI_SSOutputCmd	Enables or disables the SS output for the selected SPI.
SPI_DataSizeConfig	Configures the data size for the selected SPI.
SPI_TransmitCRC	Transmits the SPIx CRC value
SPI_CalculateCRC	Enables or disables the CRC value calculation of the transferred bytes.
SPI_GetCRC	Returns the transmit or the receive CRC register value for the specified SPI.
SPI_GetCRCPolynomial	Returns the CRC Polynomial register value for the specified SPI.
SPI_BiDirectionalLineConfig	Selects the data transfer direction in bidirectional mode for the specified SPI.
SPI_I2S_GetFlagStatus	Checks whether the specified SPI/I2S flag is set or not.
SPI_I2S_ClearFlag	Clears the SPIx/I2Sx pending flags.
SPI_I2S_GetITStatus	Checks whether the specified SPI/I2S interrupt has occurred or not.
SPI_I2S_ClearITPendingBit	Clears the SPIx/I2Sx interrupt pending bits.

9.2.1 SPI_I2S_DeInit function

describes the SPI_I2S_DeInit function.

Function name	SPI_I2S_DeInit
Function prototype	void SPI_I2S_DeInit(SPI_TypeDef* SPIx)
Behavior description	Resets the SPIx/I2Sx peripheral registers to their default reset values.
Input parameter	SPIx: where x can be 1 or 2 to select the SPI peripheral.
Output parameter	None
Return parameter	None
Required preconditions	None
Called functions	RCC_APB2PeriphClockCmd() for SPI1 RCC_APB1PeriphClockCmd() for SPI2 and SPI3

 

Example:

/* Deinitialize the SPI2 */

SPI_DeInit(SPI2);

/* Deinitialize the I2S3 */

SPI_DeInit(SPI3);

9.2.2 SPI_Init function

describes the SPI_Init function.

Function name	SPI_Init
Function prototype	void SPI_Init(SPI_TypeDef* SPIx, SPI_InitTypeDef* SPI_InitStruct)
Behavior description	Initializes the SPIx peripheral according to the parameters specified in the SPI_InitStruct.
Input parameter1	SPIx: where x can be 1, 2 or 3 to select the SPI peripheral.
Input parameter2	SPI_InitStruct: pointer to a SPI_InitTypeDef structure that contains the configuration information for the specified SPI peripheral. Refer to the SPI_InitTypeDef structure for more details on the allowed values for this parameter.
Output parameter	None
Return parameter	None
Required preconditions	None
Called functions	None

 

The SPI_InitTypeDef structure is defined in the stm32f10x_spi.h file:

typedef struct

{

u16 SPI_Direction;

u16 SPI_Mode;

u16 SPI_DataSize;

u16 SPI_CPOL;

u16 SPI_CPHA;

u16 SPI_NSS;

u16 SPI_BaudRatePrescaler;

u16 SPI_FirstBit;

u16 SPI_CRCPolynomial;

} SPI_InitTypeDef;

9.2.3 SPI_Direction

SPI_Direction configures the SPI unidirectional or bidirectional data mode. Refer to

for the values taken by this member.

SPI_Direction	Description
SPI_Direction_2Lines_FullDuplex	SPI configured as 2 lines unidirectional full duplex
SPI_Direction_2Lines_RxOnly	SPI configured as 2 lines unidirectional Rx only
SPI_Direction_1Line_Rx	SPI configured as 1 line bidirectional Rx only
SPI_Direction_1Line_Tx	SPI configured as 1 line bidirectional Tx only

9.2.4 SPI_Mode

SPI_Mode configures the SPI operating mode. Refer to for the values taken by

this member.

SPI_Mode	Description
SPI_Mode_Master	SPI configured as a master
SPI_Mode_Slave	SPI configured as a slave

9.2.5 SPI_DataSize

SPI_DataSize configures the SPI data size. Refer to for the values taken by this member.

SPI_DataSize	Description
SPI_DataSize_16b	SPI 16-bit data frame format for transmission and reception
SPI_DataSize_8b	SPI 8-bit data frame format for transmission and reception

9.2.6 SPI_CPOL

SPI_CPOL selects the serial clock steady state. Refer to for the values taken by

this member.

SPI_CPOL	Description
SPI_CPHA_2Edge	Data is captured on the second edge
SPI_CPHA_1Edge	Data is captured on the first edge

9.2.7 SPI_CPHA

SPI_CPHA configures the clock active edge for the bit capture. Refer to for the

values taken by this member.

SPI_CPHA	Description
SPI_CPHA_2Edge	Data is captured on the second edge
SPI_CPHA_1Edge	Data is captured on the first edge

9.2.8 SPI_NSS

SPI_NSS specifies whether the NSS signal is managed by hardware (NSS pin) or by

software using the SSI bit. Refer to Table 418 for the values taken by this member.

SPI_NSS	Description
SPI_NSS_Hard	NSS managed by external pin
SPI_NSS_Soft	Internal NSS signal controlled by SSI bit

9.2.9 SPI_BaudRatePrescaler

SPI_BaudRatePrescaler is used to define the Baud Rate prescaler value which will be used

to configure the transmit and receive SCK clock. Refer to for the values taken by

this member.

SPI_BaudratePrescaler	Description
SPI_BaudRatePrescaler2	Baud Rate Prescaler equal to 2
SPI_BaudRatePrescaler4	Baud Rate Prescaler equal to 4
SPI_BaudRatePrescaler8	Baud Rate Prescaler equal to 8
SPI_BaudRatePrescaler16	Baud Rate Prescaler equal to 16
SPI_BaudRatePrescaler32	Baud Rate Prescaler equal to 32
SPI_BaudRatePrescaler64	Baud Rate Prescaler equal to 64
SPI_BaudRatePrescaler128	Baud Rate Prescaler equal to 128
SPI_BaudRatePrescaler256	Baud Rate Prescaler equal to 256

9.2.10 SPI_FirstBit

SPI_FirstBit specifies whether data transfers start from MSB or LSB bit. Refer to for the values taken by this member.

SPI_FirstBit	Description
SPI_FisrtBit_MSB	First bit to transfer is the MSB
SPI_FisrtBit_LSB	First bit to transfer is the LSB

 

9.2.11 SPI_Cmd function

describes the SPI_Cmd function.

Function name	SPI_Cmd
Function prototype	void SPI_Cmd(SPI_TypeDef* SPIx, FunctionalState NewState)
Behavior description	Enables or disables the specified SPI peripheral.
Input parameter1	SPIx: where x can be 1, 2 or 3 to select the SPI peripheral.
Input parameter2	NewState: new state of the SPIx peripheral. This parameter can be: ENABLE or DISABLE.
Output parameter	None
Return parameter	None
Required preconditions	None
Called functions	None

 

Example:

/* Enable SPI3 */

SPI_Cmd(SPI3, ENABLE);

9.2.12 SPI_I2S_ITConfig function

describes the SPI_I2S_ITConfig function.

Function name	SPI_I2S_ITConfig
Function prototype	void SPI_I2S_ITConfig(SPI_TypeDef* SPIx, u8 SPI_I2S_IT, FunctionalState NewState)
Behavior description	Enables or disables the specified SPI/I2S interrupts.
Input parameter1	SPIx: where x can be 1, 2 or 3 to select the SPI peripheral.
Input parameter2	SPI_I2S_IT: SPI interrupt source to be enabled or disabled. Refer to SPI_I2S_IT for more details on the allowed values for this parameter.
Input parameter3	NewState: new state of the specified SPI/I2S interrupt. This parameter can be: ENABLE or DISABLE.
Output parameter	None
Return parameter	None
Required preconditions	None
Called functions	None

 

9.2.13 SPI_I2S_IT

SPI_I2S_IT enables or disables SPI/I2S interrupts. See for the values taken by

this parameter.

SPI_I2S_IT	Description
SPI_I2S_IT_TXE	Tx buffer empty interrupt mask
SPI_I2S_IT_RXNE	Rx buffer not empty interrupt mask
SPI_I2S_IT_ERR	Error interrupt mask

Example:

/* Enable SPI2 Tx buffer empty interrupt */

SPI_I2S_ITConfig(SPI2, SPI_I2S_IT_TXE, ENABLE);

9.2.14 SPI_I2S_SendData function

describes the SPI_I2S_SendData function.

Function name	SPI_I2S_SendData
Function prototype	void SPI_I2S_SendData(SPI_TypeDef* SPIx, u16 Data)
Behavior description	Transmits data through the SPIx/I2Sx peripheral.
Input parameter1	SPIx: where x can be 1, 2 or 3 to select the SPI peripheral.
Input parameter2	Data: Byte or half word (in SPI mode), or half word (in I2S mode) to be transmitted.
Output parameter	None
Return parameter	None
Required preconditions	None
Called functions	None

 

Example:

/* Send 0xA5 through the SPI1 peripheral */

SPI_I2S_SendData(SPI1, 0xA5);

9.2.15 SPI_I2S_ReceiveData function

describes the SPI_I2S_ReceiveData function.

Function name	SPI_I2S_ReceiveData
Function prototype	u16 SPI_I2S_ReceiveData(SPI_TypeDef* SPIx)
Behavior description	Returns the most recent data received through the SPIx/I2Sx peripheral.
Input parameter	SPIx: where x can be 1, 2 or 3 to select the SPI/I2S? peripheral.
Output parameter	None
Return parameter	The value of the received data.
Required preconditions	None
Called functions	None

 

Example:

/* Read the most recent data received by the SPI2 peripheral */

u16 ReceivedData;

ReceivedData = SPI_I2S_ReceiveData(SPI2);

9.2.16 SPI_I2S_GetFlagStatus function

describes the SPI_I2S_GetFlagStatus function.

Function name	SPI_I2S_GetFlagStatus
Function prototype	FlagStatus SPI_I2S_GetFlagStatus(SPI_TypeDef* SPIx, u16 SPI_I2S_FLAG)
Behavior description	Checks whether the specified SPI/I2S flag is set or not.
Input parameter1	SPIx: where x can be 1, 2 or 3 to select the SPI/I2S? peripheral.
Input parameter2	SPI_I2S_FLAG: flag to be checked. Refer to SPI_I2S_FLAG for more details on the allowed values for this parameter.
Output parameter	None
Return parameter	The new state of SPI_I2S_FLAG (SET or RESET).
Required preconditions	None
Called functions	None

9.2.17 SPI_I2S_FLAG

The SPI/I2S flags that can be checked by issuing an SPI_I2S_GetFlagStatus function are

listed in Table

SPI_I2S_FLAG	Description
SPI_I2S_FLAG_BSY	Busy flag
SPI_I2S_FLAG_OVR	Overrun flag
SPI_FLAG_MODF	Mode fault flag
SPI_FLAG_CRCERR	CRC error flag
I2S_FLAG_UDR	Underrun flag
I2S_FLAG_CHSIDE	Channel side flag
SPI_I2S_FLAG_TXE	Transmit buffer empty flag
SPI_I2S_FLAG_RXNE	Receive buffer not empty flag

 

Example:

/* Test if the SPI1 transmit buffer empty flag is set or not */

FlagStatus Status;

Status = SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE);

/* Get the I2S3 received (or to be transmitted) data channel side

(left or right) */

FlagStatus Status;

Status = SPI_I2S_GetFlagStatus(SPI3, I2S_FLAG_CHSIDE);

9.3實例演練

實驗一 二塊SIOC使用SPI通訊介面傳收資料

實驗說明：將一SIOC的SPI1設為master ，另一SIOC的SPI2設為slave，SPI1傳送32筆16位元的資料給SPI2，並使用VCP觀察其結果。

主要程式碼說明：

傳送端(SPI1 master)程式碼

#include "stm32f10x.h"

#include "stdio.h"

#include "hw_config.h"

#include "stm32_eval.h"

 

/* Private define ------------------------------------------------------------*/

#define BufferSize  32 //傳送資料buffer大小

 

/* Private variables ---------------------------------------------------------*/

SPI_InitTypeDef  SPI_InitStructure;

/*傳送資料，32筆16位元資料*/

uint16_t SPI1_Buffer_Tx[BufferSize] = {1, 2, 3, 4, 5, 6,

                                7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32};

uint32_t TxIdx = 0; //

/* Private functions ---------------------------------------------------------*/

void RCC_Configuration(void);//設定SPI RCC

void GPIO_Configuration(void);//設定SPI GPIO

 

int main(void)

{

  int a,b;

  Set_System();

  /* SPI clocks configuration ---------------------------------------------*/

  RCC_Configuration();

  /* SPI GPIO configuration ------------------------------------------------------*/

  GPIO_Configuration();

 

  /* SPI1 configuration ------------------------------------------------------*/

  SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;

  SPI_InitStructure.SPI_Mode = SPI_Mode_Master;

  SPI_InitStructure.SPI_DataSize = SPI_DataSize_16b;

  SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;

  SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;

  SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;

  SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_8;

  SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB; 

  SPI_Init(SPI1, &SPI_InitStructure); 

 

  /* Enable SPI1 */

  SPI_Cmd(SPI1, ENABLE);

 

  /* Transfer procedure */

  while (TxIdx < BufferSize )

  {

    /* Wait for SPI1 Tx buffer empty */

    while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);

    /* Send SPI1 data */

    SPI_I2S_SendData(SPI1, SPI1_Buffer_Tx[TxIdx++]);   

  }

 

  while (1)

  {

      getchar();

/**********************/

    /*使用VCP印出傳送資料*/

        b = 0;

        while (b<  32 )

        {

         printf("SPI1 Tx %d : %d\n\r",b,SPI1_Buffer_Tx[b]);

         b++;

        }

/**********************/

  }

}

void RCC_Configuration(void)

{

  /* PCLK2 = HCLK/2 */

  RCC_PCLK2Config(RCC_HCLK_Div2);

 

  /* Enable peripheral clocks --------------------------------------------------*/

  /* GPIOA, GPIOB and SPI1 clock enable */

  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB |

                         RCC_APB2Periph_SPI1, ENABLE);

}

 

void GPIO_Configuration(void)

{

  GPIO_InitTypeDef GPIO_InitStructure;

 

  /* Configure SPI1 pins: SCK, MISO and MOSI ---------------------------------*/

  /* Confugure SCK and MOSI pins as Alternate Function Push Pull */

  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_7;

  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;

  GPIO_Init(GPIOA, &GPIO_InitStructure);

 

  /* Confugure MISO pin as Input Floating  */

  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;

  GPIO_Init(GPIOA, &GPIO_InitStructure);

}

接送端(SPI2 slave)程式碼

#include "stm32f10x.h"

#include "stdio.h"

#include "hw_config.h"

#include "stm32_eval.h"

 

/* Private define ------------------------------------------------------------*/

#define BufferSize  32 //接收資料buffer大小

 

/* Private variables ---------------------------------------------------------*/

SPI_InitTypeDef  SPI_InitStructure;

/*接收資料，32筆16位元資料*/

uint16_t  SPI2_Buffer_Rx[BufferSize]={0 };

uint32_t RxIdx = 0;

/* Private functions ---------------------------------------------------------*/

void RCC_Configuration(void);//設定SPI RCC

void GPIO_Configuration(void);//設定SPI GPIO

 

int main(void)

{

  int a,b;

  Set_System();

  /* SPI clocks configuration ---------------------------------------------*/

  RCC_Configuration();

  /* SPI GPIO configuration ------------------------------------------------------*/

  GPIO_Configuration();

 

  /* SPI2 configuration ------------------------------------------------------*/

  SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;

  SPI_InitStructure.SPI_Mode = SPI_Mode_Slave;

  SPI_InitStructure.SPI_DataSize = SPI_DataSize_16b;

  SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;

  SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;

  SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;

  SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_8;

  SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;   

  SPI_Init(SPI2, &SPI_InitStructure);

 

  /* Enable SPI2 */

  SPI_Cmd(SPI2, ENABLE);    

 

  /* received procedure */

  while (RxIdx< BufferSize )

  {

    /* Wait for SPI2 data reception */

   while (SPI_I2S_GetFlagStatus(SPI2, SPI_I2S_FLAG_RXNE) == RESET);

    /* Read SPI2 received data */

     SPI2_Buffer_Rx[RxIdx++] = SPI_I2S_ReceiveData(SPI2);

 }  

 

  while (1)

  {

      getchar();

/**********************/

    /*使用VCP印出接收資料*/

        b = 0;

        while (b<  32 )

        {

         printf("SPI2 Rx %d : %d\n\r",a,SPI2_Buffer_Rx[a]);

         b++;

        }

/**********************/

  }

}

void RCC_Configuration(void)

{

  /* PCLK2 = HCLK/2 */

  RCC_PCLK2Config(RCC_HCLK_Div2);

 

  /* Enable peripheral clocks --------------------------------------------------*/

  /* SPI2 Periph clock enable */

  RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI2, ENABLE);

}

 

void GPIO_Configuration(void)

{

  GPIO_InitTypeDef GPIO_InitStructure;

 

   /* Configure SPI2 pins: SCK, MISO and MOSI ---------------------------------*/

  /* Confugure SCK and MOSI pins as Input Floating */

  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13 | GPIO_Pin_15;

  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;

  GPIO_Init(GPIOB, &GPIO_InitStructure);

  /* Confugure MISO pin as Alternate Function Push Pull */

  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_14;

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;

  GPIO_Init(GPIOB, &GPIO_InitStructure);

}

 

 

 

 

接線示意圖

 

 

實驗結果

 

 

COM4為SPI1結果，COM9為SPI2結果

 

實驗二 可變資料筆數的傳收

實驗說明：接續實驗一，SPI1可設定傳送資料筆數，SPI2接收設定資料筆數的資料，SPI1先傳送資料筆數給SPI2，之後SPI2依照接收的數目，接收資料。

主要程式碼說明：

傳送端(SPI1 master)程式碼

#include "stm32f10x.h"

#include "stdio.h"

#include "hw_config.h"

#include "stm32_eval.h"

 

/* Private define ------------------------------------------------------------*/

#define BufferSize  32 //傳送資料buffer大小

 

/* Private variables ---------------------------------------------------------*/

SPI_InitTypeDef  SPI_InitStructure;

/*傳送資料，32筆16位元資料*/

uint16_t SPI1_Buffer_Tx[BufferSize] = {1, 2, 3, 4, 5, 6,

                                7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32};

uint32_t TxIdx = 0; //

/* Private functions ---------------------------------------------------------*/

void RCC_Configuration(void);//設定SPI RCC

void GPIO_Configuration(void);//設定SPI GPIO

 

int main(void)

{

  int a;//傳送筆數

  Set_System();

  /* SPI clocks configuration ---------------------------------------------*/

  RCC_Configuration();

  /* SPI GPIO configuration ------------------------------------------------------*/

  GPIO_Configuration();

 

  /* SPI1 configuration ------------------------------------------------------*/

  SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;

  SPI_InitStructure.SPI_Mode = SPI_Mode_Master;

  SPI_InitStructure.SPI_DataSize = SPI_DataSize_16b;

  SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;

  SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;

  SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;

  SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_8;

  SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB; 

  SPI_Init(SPI1, &SPI_InitStructure); 

 

  /* Enable SPI1 */

  SPI_Cmd(SPI1, ENABLE);

 

  while (1)

  {

      getchar();

    /********************************/

    //設定傳送資料量

        printf("input BufferSize :");

        scanf("%d",&a);

        printf("\n\r");                                            

        /********************************/

    

    //傳送要預傳送資料量

      while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);

    SPI_I2S_SendData(SPI1, a);

       

      /* Transfer procedure */

TxIdx = 0;

      while (TxIdx < a )

      {

            /* Wait for SPI1 Tx buffer empty */

            while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);

            SPI_I2S_SendData(SPI1, SPI1_Buffer_Tx[TxIdx++]);      

      }

}

}

接送端(SPI2 slave)程式碼

#include "stm32f10x.h"

#include "stdio.h"

#include "hw_config.h"

#include "stm32_eval.h"

 

/* Private define ------------------------------------------------------------*/

#define BufferSize  32 //接收資料buffer大小

 

/* Private variables ---------------------------------------------------------*/

SPI_InitTypeDef  SPI_InitStructure;

/*接收資料，32筆16位元資料*/

uint16_t  SPI2_Buffer_Rx[BufferSize]={0 };

uint32_t RxIdx = 0;

/* Private functions ---------------------------------------------------------*/

void RCC_Configuration(void);//設定SPI RCC

void GPIO_Configuration(void);//設定SPI GPIO

 

int main(void)

{

  int a,b;//b為接收筆數

  Set_System();

  /* SPI clocks configuration ---------------------------------------------*/

  RCC_Configuration();

  /* SPI GPIO configuration ------------------------------------------------------*/

  GPIO_Configuration();

 

  /* SPI2 configuration ------------------------------------------------------*/

  SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;

  SPI_InitStructure.SPI_Mode = SPI_Mode_Slave;

  SPI_InitStructure.SPI_DataSize = SPI_DataSize_16b;

  SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;

  SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;

  SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;

  SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_8;

  SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;   

  SPI_Init(SPI2, &SPI_InitStructure);

 

  /* Enable SPI2 */

  SPI_Cmd(SPI2, ENABLE);    

 

  while (1)

  {  

      while (SPI_I2S_GetFlagStatus(SPI2, SPI_I2S_FLAG_RXNE) == RESET);

    /* 接收要接收的資料數量 */

     b = SPI_I2S_ReceiveData(SPI2);

         /* received procedure */

RxIdx = 0;

  while (RxIdx< b)

  {

    /* Wait for SPI2 data reception */

   while (SPI_I2S_GetFlagStatus(SPI2, SPI_I2S_FLAG_RXNE) == RESET);

    /* Read SPI2 received data */

   SPI2_Buffer_Rx[RxIdx] = SPI_I2S_ReceiveData(SPI2);

     RxIdx++;                  

  }                                                         

       

/**********************/

    /*使用VCP印出接收資料*/

        printf("get data %d\n\r",b);

        a = 0;

        while (a <  b)

        {

         printf("SPI2 Rx%d : %d\n\r",a,SPI2_Buffer_Rx[a]);

         a++;

        };     

/**********************/

  }

}

實驗結果

 

 

 

COM4為SPI1結果，COM9為SPI2結果

實驗三 傳送32位元的資料

實驗說明：接續實驗一，SPI1傳送16筆32位元的資料給SPI2，因為傳收和接收buffer，只有16位元，所以SPI1先將32位元的資料拆成二筆16位元的資料，再傳給SPI2，而SPI2收到後，再將二筆16位元資料組成一筆32位元資料。

主要程式碼說明：

傳送端(SPI1 master)程式碼

#include "stm32f10x.h"

#include "stdio.h"

#include "hw_config.h"

#include "stm32_eval.h"

 

/* Private define ------------------------------------------------------------*/

#define BufferSize  32 //傳送資料buffer大小

 

/* Private variables ---------------------------------------------------------*/

SPI_InitTypeDef  SPI_InitStructure;

/*傳送資料，16筆32位元資料*/

uint32_t SPI1_Buffer_Data[BufferSize/2] = {65536,65537,65538,65539,65540,65541,65542,65543,65544,65545,65546,65547,65548,65549,65550,65551}; uint32_t TxIdx = 0; //

/* Private functions ---------------------------------------------------------*/

void RCC_Configuration(void);//設定SPI RCC

void GPIO_Configuration(void);//設定SPI GPIO

 

int main(void)

{

  int a;//傳送筆數

  Set_System();

  /* SPI clocks configuration ---------------------------------------------*/

  RCC_Configuration();

  /* SPI GPIO configuration ------------------------------------------------------*/

  GPIO_Configuration();

 

  /* SPI1 configuration ------------------------------------------------------*/

  SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;

  SPI_InitStructure.SPI_Mode = SPI_Mode_Master;

  SPI_InitStructure.SPI_DataSize = SPI_DataSize_16b;

  SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;

  SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;

  SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;

  SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_8;

  SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB; 

  SPI_Init(SPI1, &SPI_InitStructure); 

 

  /* Enable SPI1 */

  SPI_Cmd(SPI1, ENABLE);

 

 /* Transfer procedure */

  while (TxIdx < BufferSize )

  {

    /* Wait for SPI1 Tx buffer empty */

    while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);

       

    //將32位元資料拆成二筆16位元資料

        if(TxIdx % 2 == 0)

     SPI1_Buffer_Tx[TxIdx] = ((SPI1_Buffer_Data[TxIdx/2] & 0xffff0000) >> 16);

        else 

         SPI1_Buffer_Tx[TxIdx] = ((SPI1_Buffer_Data[TxIdx/2] & 0x0000ffff));

 

    /* Send SPI1 data */      

    SPI_I2S_SendData(SPI1, SPI1_Buffer_Tx[TxIdx++]);   

  }

  while (1)

  {                                                                   

        getchar();

        printf("transmit complete\n\r");

        a = 0;

        while(a < 16)

        {

           printf("%d\n\r",SPI1_Buffer_Data[a]);

           a++;

        }   

  }

}

接送端(SPI2 slave)程式碼

#include "stm32f10x.h"

#include "stdio.h"

#include "hw_config.h"

#include "stm32_eval.h"

 

/* Private define ------------------------------------------------------------*/

#define BufferSize  32 //接收資料buffer大小

 

/* Private variables ---------------------------------------------------------*/

SPI_InitTypeDef  SPI_InitStructure;

/*接收資料，16筆32位元資料*/

uint32_t SPI2_Buffer_Data[BufferSize/2]={55,55,55,

55,55,55,55,55,55,55,55,55,55,55};

uint32_t RxIdx = 0;

/* Private functions ---------------------------------------------------------*/

void RCC_Configuration(void);//設定SPI RCC

void GPIO_Configuration(void);//設定SPI GPIO

 

int main(void)

{

  int a,b;//b為接收筆數

  Set_System();

  /* SPI clocks configuration ---------------------------------------------*/

  RCC_Configuration();

  /* SPI GPIO configuration ------------------------------------------------------*/

  GPIO_Configuration();

 

  /* SPI2 configuration ------------------------------------------------------*/

  SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;

  SPI_InitStructure.SPI_Mode = SPI_Mode_Slave;

  SPI_InitStructure.SPI_DataSize = SPI_DataSize_16b;

  SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;

  SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;

  SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;

  SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_8;

  SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;   

  SPI_Init(SPI2, &SPI_InitStructure);

 

  /* Enable SPI2 */

  SPI_Cmd(SPI2, ENABLE);    

    /* received procedure */

  while (RxIdx< BufferSize )

  {

       /* Wait for SPI2 data reception */

    while (SPI_I2S_GetFlagStatus(SPI2, SPI_I2S_FLAG_RXNE) == RESET);

     /* Read SPI2 received data */

      SPI2_Buffer_Rx[RxIdx] = SPI_I2S_ReceiveData(SPI2);

         //將二筆16位元資料組成一筆32位元

         if(RxIdx % 2 == 0)

                  SPI2_Buffer_Data[RxIdx/2] = SPI2_Buffer_Rx[RxIdx] << 16;

         else

               SPI2_Buffer_Data[RxIdx/2] += SPI2_Buffer_Rx[RxIdx] ;

        RxIdx++; 

  }

 

  while (1)

  {                                                                   

        getchar();

       

        a = 0;

        while (a <  BufferSize/2)

        {

         printf("SPI2 RX%d : %d\n\r",a,SPI2_Buffer_Data[a]);

         a++;

        }

  }

}

實驗結果

 

 

COM4為SPI1結果，COM9為SPI2結果