网站建设有什么优势头条今日头条

一、开启时钟，开启SPI和GPIO的时钟

二、初始化GPIO口，其中SCK和MOSI是由硬件外设控制的输出信号，配置为复用推挽输出

MISO是硬件外设的输入信号，配置为上拉输入，SS是软件控制的输出信号，配置为通用推挽输出

三、配置SPI外设，使用结构体调用SPI_Init

四、开关控制，调用SPI_Cmd,使能

 void SPI_I2S_SendData(SPI_TypeDef* SPIx, uint16_t Data);//写DR数据寄存器

uint16_t SPI_I2S_ReceiveData(SPI_TypeDef* SPIx);//读DR

步骤

一、等待TXE为1，发送寄存器为空

二、软件写入数据置SPI_DR

三、等待RENE为1

四、读取DR 

MySPI.c

#include "stm32f10x.h"                  // Device headervoid MySPI_W_SS(uint8_t BitValue)	//ss = cs
{GPIO_WriteBit(GPIOA , GPIO_Pin_4, (BitAction)BitValue);
}void MySPI_Init(void)
{RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);GPIO_InitTypeDef GPIO_InitStructure;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOA, &GPIO_InitStructure);GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_7;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOA, &GPIO_InitStructure);GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOA, &GPIO_InitStructure);SPI_InitTypeDef SPI_InitStructure;SPI_InitStructure.SPI_Mode = SPI_Mode_Master;	//指定为主机SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;	//双线全双工SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;	//8位数据帧SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;	//高位先行SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_128;SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge;	//第一个边沿开始采样CPHA=0SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;SPI_InitStructure.SPI_CRCPolynomial = 7;SPI_Init(SPI1, &SPI_InitStructure);SPI_Cmd(SPI1 , ENABLE);MySPI_W_SS(1);
}void MySPI_Start(void)
{MySPI_W_SS(0);
}void MySPI_Stop(void)
{MySPI_W_SS(1);
}uint8_t MySPI_SwapByte(uint8_t ByteSend)	//交换字节
{while (SPI_I2S_GetFlagStatus(SPI1 , SPI_I2S_FLAG_TXE) != SET);SPI_I2S_SendData(SPI1 , ByteSend);while (SPI_I2S_GetFlagStatus(SPI1 , SPI_I2S_FLAG_RXNE) != SET);return SPI_I2S_ReceiveData(SPI1);
}