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#include "SPI.h"
void MySPI_W_SS(uint8_t BitValue) //SS 还是使用软件模拟
{
GPIO_WriteBit(GPIOC, GPIO_Pin_0, (BitAction)BitValue); //BitAction 非0即1
}
void MySPI_Init(void)
{
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC, 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_0; // SS:PC0
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOC, &GPIO_InitStructure);
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_7; // CLK:PA5 DI/MOSI:PA7
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; //MISO:PA6
GPIO_Init(GPIOA, &GPIO_InitStructure);
//SPI初始化
SPI_InitTypeDef SPI_InitStructure;
SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_128; //分频 72Mhz/128
SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge; //第一个边沿采样
SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;
SPI_InitStructure.SPI_CRCPolynomial = 7; //手册489页最红有提到默认值为 0x0007
SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b; //8位数据帧
SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex; //双线全双工
SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB; //高位先行
SPI_InitStructure.SPI_Mode = SPI_Mode_Master; //选择为主机
SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
SPI_Init(SPI1, &SPI_InitStructure);
SPI_Cmd(SPI1, ENABLE);
//默认给SS输出高电平
MySPI_W_SS(0);
}
//初始信号
void MySPI_Start(void)
{
MySPI_W_SS(0);
}
//终止信号
void MySPI_Stop(void)
{
MySPI_W_SS(1);
}
//通过交换一个字节接收到的数据
uint8_t MySPI_SwapByte(uint8_t ByteSend)
{
while(SPI_I2S_GetFlagStatus(SPI1,SPI_I2S_FLAG_TXE) != SET); //等待TXE为1
SPI_I2S_SendData(SPI1, ByteSend); //发送数据，写入DR时会自动清除TXE标志位
while(SPI_I2S_GetFlagStatus(SPI1,SPI_I2S_FLAG_RXNE) != SET); //等待RXNE为1
return SPI_I2S_ReceiveData(SPI1); //接收数据，读DR时会自动清除RXNE标志位
}
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