解决STM32 SPI 半残废 NSS无法拉高

void GPIO_SPI12_Config(void)

{

GPIO_InitTypeDef GPIO_InitStructure;

//----- 第1步：打开SPI部件的时钟 --------------------------------------------------------------------------------------------

RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);

//----- 第2步：打开SPI相关的引脚为复用推挽输出 -----------------------------------------------------------------------------

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_DOWN;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_Level_3;

/* SPI SCK pin configuration */

GPIO_InitStructure.GPIO_Pin = SPI12_SCK_PIN;

GPIO_Init(SPI12_SCK_GPIO_PORT, &GPIO_InitStructure);

/* SPI MOSI pin configuration */

GPIO_InitStructure.GPIO_Pin = SPI12_MOSI_PIN;

GPIO_Init(SPI12_MOSI_GPIO_PORT, &GPIO_InitStructure);

/* SPI MISO pin configuration */

GPIO_InitStructure.GPIO_Pin = SPI12_MISO_PIN;

GPIO_Init(SPI12_MISO_GPIO_PORT, &GPIO_InitStructure);

// STM32 SPI 的CS引脚不会自动拉高，所以用GPIO中断代替

// GPIO_InitStructure.GPIO_Pin = SPI12_CS_PIN;

// GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;

// GPIO_Init(SPI12_CS_GPIO_PORT, &GPIO_InitStructure);

GPIO_PinAFConfig(SPI12_SCK_GPIO_PORT, SPI12_SCK_SOURCE, SPI12_SCK_AF);

GPIO_PinAFConfig(SPI12_MOSI_GPIO_PORT, SPI12_MOSI_SOURCE, SPI12_MOSI_AF);

GPIO_PinAFConfig(SPI12_MISO_GPIO_PORT, SPI12_MISO_SOURCE, SPI12_MISO_AF);

// GPIO_PinAFConfig(SPI12_CS_GPIO_PORT, SPI12_CS_SOURCE, SPI12_CS_AF);

}

void SPI12_Config(void)

{

SPI_InitTypeDef SPI_InitStructure;

SPI_RxFIFOThresholdConfig(SPI1,SPI_RxFIFOThreshold_QF);

//----- 第3步：配置SPI的参数设定 --------------------------------------------------------------------------------------------

SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex; //双线双向全双工

SPI_InitStructure.SPI_Mode = SPI_Mode_Slave; //设置为主模式SPI

SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b; //发送接收8 位数据

SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low; //时钟悬空为低

SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge; //数据捕获于第二个时钟沿

SPI_InitStructure.SPI_NSS = SPI_NSS_Soft; //NSS 信号由软件管理

SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_4; //设置波特率为去64 分频

SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB; //数据传输从MSB 位开始

SPI_InitStructure.SPI_CRCPolynomial = 7; //校验

SPI_Init(SPI1, &SPI_InitStructure);

SPI_I2S_DMACmd(SPI1,SPI_I2S_DMAReq_Tx,DISABLE);

SPI_I2S_DMACmd(SPI1,SPI_I2S_DMAReq_Rx,DISABLE);

SPI_ITConfig(SPI1, SPI_IT_RXNE,DISABLE); //接收中断失能

SPI_ITConfig(SPI1, SPI_IT_TXE, DISABLE); //发送中断失能

//----- 第4步：使能SPI1， 配置完毕 ------------------------------------------------------------------------------------------

SPI_Cmd(SPI1, DISABLE);

}

void Exti_15_Init(void)

{

NVIC_InitTypeDef NVIC_InitStructure;

GPIO_InitTypeDef GPIO_InitStructure;

EXTI_InitTypeDef EXTI_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE); // 配置中断时钟

//----- 设置外部中断引脚，用户根据实际情况自行修改 ------------------------------------------------------------------------------

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_15;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN; // 输入

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_Level_2; // 快速

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; // 上拉

GPIO_Init(GPIOA, &GPIO_InitStructure);

//----- 设置NVIC初始化 ------------------------------------------------------------------------------

NVIC_InitStructure.NVIC_IRQChannel = EXTI4_15_IRQn; // 中断通道

NVIC_InitStructure.NVIC_IRQChannelPriority = 0; // 中断优先级(0-3)

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; // 使能

NVIC_Init(&NVIC_InitStructure);

SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, GPIO_PinSource15); //连接中断线路

EXTI_InitStructure.EXTI_Line = EXTI_Line15; //设置中断线路

EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;

EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising_Falling; //双沿触发

EXTI_InitStructure.EXTI_LineCmd = ENABLE; //中断线使能

EXTI_Init(&EXTI_InitStructure); //初始化中断

}

void SPI1_NSS_Handler(void)

{

if(GPIO_ReadInputDataBit(SPI12_CS_GPIO_PORT,SPI12_CS_PIN)!=RESET)

{

SPI_Cmd(SPI1,DISABLE);

}

else

{

SPI_Cmd(SPI1,ENABLE);

}

}

void EXTI4_15_IRQHandler(void)

{

if(EXTI_GetITStatus(EXTI_Line15) != RESET)

{

EXTI_ClearITPendingBit(EXTI_Line15);

SPI1_NSS_Handler();

}

}