#include "stm32f10x.h"
/* RCC时钟配置 */
void RCC_config(void)
{
ErrorStatus HSEStartUpStatus;
/* RCC寄存器设置为默认配置 */
RCC_DeInit();
/* 打开外部高速时钟 */
RCC_HSEConfig(RCC_HSE_ON);
/* 等待外部高速时钟稳定 */
HSEStartUpStatus = RCC_WaitForHSEStartUp();
if(HSEStartUpStatus == SUCCESS)
{
/* 设置HCLK = SYSCLK */
RCC_HCLKConfig(RCC_SYSCLK_Div1);
/* 设置PCLK2 = HCLK */
RCC_PCLK2Config(RCC_HCLK_Div1);
/* 设置PCLK1 = HCLK / 2 */
RCC_PCLK1Config(RCC_HCLK_Div2);
// /* 设置FLASH代码延时 */
// FLASH_SetLatency(FLASH_Latency_2);
// /* 使能预取址缓存 */
// FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);
/* 设置PLL时钟源为HSE倍频9 72MHz */
RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9);
/* 使能PLL */
RCC_PLLCmd(ENABLE);
/* 等待PLL稳定 */
while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET);
/* 设置PLL为系统时钟源 */
RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);
/* 等待系统时钟源切换到PLL */
while(RCC_GetSYSCLKSource() != 0x08);
}
}
/* GPIO配置 */
void GPIO_config(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
/* 时钟配置 */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
/* MISO配置为复用推挽输出 */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* SCK和MOSI配置为浮空输入 */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_7;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* NSS配置为浮空输入 */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &GPIO_InitStructure);
}
/* SPI配置 */
void SPI_config(void)
{
SPI_InitTypeDef SPI_InitStructure;
/* 时钟配置 */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO | RCC_APB2Periph_SPI1, ENABLE);
/* 配置SPI模式 */
SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
SPI_InitStructure.SPI_Mode = SPI_Mode_Slave;
SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;
SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge;
SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_4;
SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
SPI_InitStructure.SPI_CRCPolynomial = 7;
SPI_Init(SPI1, &SPI_InitStructure);
/* 打开SPI1 */
SPI_Cmd(SPI1, ENABLE);
/* 使能DMA接收 */
SPI_I2S_DMACmd(SPI1, SPI_I2S_DMAReq_Rx, ENABLE);
}
uint8_t rx_buf[100];
/* DMA配置 */
void DMA_config(void)
{
DMA_InitTypeDef DMA_InitStructure;
/* 使能DMA1时钟 */
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
DMA_DeInit(DMA1_Channel2);
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)(&SPI1->DR);
DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)rx_buf;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStructure.DMA_BufferSize = 100;
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_Channel2, &DMA_InitStructure);
DMA_Cmd(DMA1_Channel2, ENABLE);
}
/* 中断嵌套控制器配置 */
void NVIC_config(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
/* 选择中断分组2 */
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
/* 设置外部中断4的先占优先级为3,从占优先级为3 */
NVIC_InitStructure.NVIC_IRQChannel = EXTI4_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}
/* 外部中断配置 */
void EXIT_config(void)
{
EXTI_InitTypeDef EXTI_InitStructure;
/* 将GPIOA_0和中断线连接 */
GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource4);
/* 设置中断线0位外部下降沿中断 */
EXTI_InitStructure.EXTI_Line = EXTI_Line4;
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
EXTI_InitStructure.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStructure);
}
/* 毫秒延时函数 */
void delay_ms(uint16_t time)
{
uint16_t i = 0;
while(time--)
{
i = 12000;
while(i--);
}
}
/* 主函数 */
int main(void)
{
/* RCC时钟配置 */
RCC_config();
/* GPIO配置 */
GPIO_config();
/* 外部中断配置 */
EXIT_config();
/* 中断嵌套控制器配置 */
NVIC_config();
/* DMA配置 */
DMA_config();
/* SPI配置 */
SPI_config();
while(1)
{
delay_ms(1000);
}
}
/* 外部中断4 */
void EXTI4_IRQHandler(void)
{
volatile uint8_t len;
/* 检查中断状态 */
if(EXTI_GetITStatus(EXTI_Line4) != RESET)
{
len = 100 - DMA1_Channel2->CNDTR;
/* 接收完成,修改接收通道数据个数 */
DMA_Cmd(DMA1_Channel2, DISABLE);
DMA1_Channel2->CNDTR = 100;
DMA1_Channel2->CMAR = (uint32_t)rx_buf;
DMA_Cmd(DMA1_Channel2, ENABLE);
/* 清除中断状态寄存器 */
EXTI_ClearITPendingBit(EXTI_Line4);
}
}
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