stm32_template/system_Template/SPI.c

#include "main.h"

static void SPI1_Init(void);
static void SPI2_Init(void);
static uint8_t SPI_WriteRead(SPI_TypeDef* SPIx, uint8_t data, uint32_t timeout);
static uint8_t SPI_CS_WritePin(SPI_TypeDef* SPIx, uint8_t bitVal);

SPIClassStruct SPIClass = {
	.SPI1_Init = SPI1_Init,
	.SPI2_Init = SPI2_Init,
	.WriteRead = SPI_WriteRead,
	.WriteCSPin = SPI_CS_WritePin
};
// SPI1 CS
#define SPI1_CS_GPIO_PORT    		GPIOB
#define SPI1_CS_GPIO_CLK 	    	RCC_APB2Periph_GPIOB
#define SPI1_CS_GPIO_PIN			GPIO_Pin_0
// SPI2 CS
#define SPI2_CS_GPIO_PORT    		GPIOA
#define SPI2_CS_GPIO_CLK 	    	RCC_APB2Periph_GPIOA
#define SPI2_CS_GPIO_PIN			GPIO_Pin_0

/**
  * @brief  SPI1初始化
  * @param  None
  * @retval None
  */
static void SPI1_Init(void)
{
	GPIO_InitTypeDef  GPIO_InitStructure;
	SPI_InitTypeDef  SPI_InitStructure;
	
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
	// SPI1 SCK-PA5  MOSI-PA7
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_7;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOA, &GPIO_InitStructure);
	// SPI1 MISO-PA6
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
	GPIO_Init(GPIOA, &GPIO_InitStructure);
	// software CS user write
	RCC_APB2PeriphClockCmd(SPI1_CS_GPIO_CLK, ENABLE);
	GPIO_InitStructure.GPIO_Pin = SPI1_CS_GPIO_PIN;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
	GPIO_Init(SPI1_CS_GPIO_PORT, &GPIO_InitStructure);
	GPIO_WriteBit(SPI1_CS_GPIO_PORT, SPI1_CS_GPIO_PIN, 1); // 拉高片选引脚
	
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE); // SPI1时钟使能

	SPI_Cmd(SPI1, DISABLE);
	SPI_I2S_DeInit(SPI1);
	SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex; // SPI设置为双线全双工
	SPI_InitStructure.SPI_Mode = SPI_Mode_Master; // 设置SPI为主模式
	SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b; // SPI发送接收8位帧结构
	SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low; // SPI时钟空闲时为低电平
	SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge; // 第一个时钟沿开始采样数据
	SPI_InitStructure.SPI_NSS = SPI_NSS_Soft; // CS信号由软件管理
	SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_16; // SPI波特率预分频值 72M / Prescaler
	SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB; // 数据传输从MSB位开始
	SPI_InitStructure.SPI_CRCPolynomial = 7; // CRC值计算的多项式

	SPI_Init(SPI1, &SPI_InitStructure); // 根据SPI_InitStruct中指定的参数初始化外设SPI寄存器
	SPI_Cmd(SPI1, ENABLE); // 使能SPI
}

/**
  * @brief  SPI1初始化
  * @param  None
  * @retval None
  */
static void SPI2_Init(void)
{
	GPIO_InitTypeDef  GPIO_InitStructure;
	SPI_InitTypeDef  SPI_InitStructure;
	
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
	// SPI1 SCK-PB13  MOSI-PB15
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13 | GPIO_Pin_15;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOB, &GPIO_InitStructure);
	// SPI1 MISO-PB14
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_14;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
	GPIO_Init(GPIOB, &GPIO_InitStructure);
	// software CS user write
	RCC_APB2PeriphClockCmd(SPI2_CS_GPIO_CLK, ENABLE);
	GPIO_InitStructure.GPIO_Pin = SPI2_CS_GPIO_PIN;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
	GPIO_Init(SPI2_CS_GPIO_PORT, &GPIO_InitStructure);
	GPIO_WriteBit(SPI2_CS_GPIO_PORT, SPI2_CS_GPIO_PIN, 1); // 拉高片选引脚
	
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI2, ENABLE); // SPI2时钟使能

	SPI_Cmd(SPI2, DISABLE);
	SPI_I2S_DeInit(SPI2);
	SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex; // SPI设置为双线全双工
	SPI_InitStructure.SPI_Mode = SPI_Mode_Master; // 设置SPI为主模式
	SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b; // SPI发送接收8位帧结构
	SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low; // SPI时钟空闲时为低电平
	SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge; // 第一个时钟沿开始采样数据
	SPI_InitStructure.SPI_NSS = SPI_NSS_Soft; // CS信号由软件管理
	SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_8; // SPI波特率预分频值 36M / Prescaler
	SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB; // 数据传输从MSB位开始
	SPI_InitStructure.SPI_CRCPolynomial = 7; // CRC值计算的多项式

	SPI_Init(SPI2, &SPI_InitStructure); // 根据SPI_InitStruct中指定的参数初始化外设SPI寄存器
	SPI_Cmd(SPI2, ENABLE); // 使能SPI
}
/**
  * @brief  SPI读写函数
  * @param  None
  * @retval 0-超时 
  */
static uint8_t SPI_WriteRead(SPI_TypeDef* SPIx, uint8_t data, uint32_t timeout)
{
	uint32_t retry = 0;				 	
	/* Loop while DR register in not emplty */
	while (SPI_I2S_GetFlagStatus(SPIx, SPI_I2S_FLAG_TXE) == RESET) // 发送缓存标志位为空
	{
		retry++;
		if(retry > timeout) return 0;
	}			  
	SPI_I2S_SendData(SPIx, data); // 通过外设SPI2发送一个数据
	retry = 0;
	/* Wait to receive a byte */
	while (SPI_I2S_GetFlagStatus(SPIx, SPI_I2S_FLAG_RXNE) == RESET) // 接收缓存标志位不为空
	{
		retry++;
		if(retry > timeout) return 0;
	}	  						    
	/* Return the byte read from the SPI bus */
	return SPI_I2S_ReceiveData(SPIx); // 通过SPI2返回接收数据	
}
/**
  * @brief  SPI读写函数
  * @param  None
  * @retval 0-成功
  */
static uint8_t SPI_CS_WritePin(SPI_TypeDef* SPIx, uint8_t bitVal)
{
	if(bitVal != RESET && bitVal != SET) return 1;
	if(SPIx == SPI1) {
		GPIO_WriteBit(SPI1_CS_GPIO_PORT, SPI1_CS_GPIO_PIN, bitVal);
	} else if(SPIx == SPI2) {
		GPIO_WriteBit(SPI2_CS_GPIO_PORT, SPI2_CS_GPIO_PIN, bitVal);
	}
	return 0;
}