工程师们好,最近我在调试l151的spi2时,发现其无法工作
spi2的初始化代码如下:
void SPI2_GPIO_INIT(void){RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOB, ENABLE); RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI2, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12|GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_40MHz; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;GPIO_Init(GPIOB, GPIO_InitStructure);
NVIC_InitStructure.NVIC_IRQChannel=SPI2_IRQn;NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;NVIC_InitStructure.NVIC_IRQChannelPreemp
tionPriority=2;NVIC_InitStructure.NVIC_IRQChannelSubPriority=2;NVIC_Init( NVIC_InitStructure);
SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;//SPI_InitStructure.SPI_Mode = SPI_Mode_Slave;//设置为SPI的从机模式SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;//SPI数据大小:发送8位帧数据结构SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;//空闲状态时SCK的状态为低电平SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge;//时钟相位,1表示在SCK的奇数沿边采样,2表示偶数沿边采样SPI_InitStructure.SPI_NSS = SPI_NSS_Hard; //NSS由硬件片选SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_2;//时钟的预分频值(0~256) 不影响传输速率SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB; //MSB高位在前SPI_InitStructure.SPI_CRCPolynomial = 7; //CRC较验和的多项式
SPI_Init(SPI2, SPI_InitStructure); //初始化SPI2的配置项SPI_I2S_ITConfig(SPI2,SPI_I2S_IT_RXNE,ENABLE);//开启中断SPI_Cmd(SPI2,ENABLE); //使能SPI2 }
读/写的函数如下:
uint8_t SPI2_ReadByte(uint8_t TxData){uint8_t count;
while (SPI_I2S_GetFlagStatus(SPI2, SPI_I2S_FLAG_RXNE) == RESET) //检查指定的SPI标志位设置与否:接受缓存非空标志位{count++;if(count>200)return 0; //如果200个计数还没完成发送,就返回0跳出这个函数}
return SPI_I2S_ReceiveData(SPI2); //返回接收的数据}
void SPI2_WriteByte(uint8_t TxData){uint8_t count;
while (SPI_I2S_GetFlagStatus(SPI2, SPI_I2S_FLAG_TXE) == RESET) //检查指定的SPI标志位设置与否:发送缓存空标志位{count++;if(count>200)return;}
SPI_I2S_SendData(SPI2, TxData); }
中断函数如下:
void SPI2_IRQHandler(void){if(SPI_I2S_GetFlagStatus(SPI2,SPI_I2S_FLAG_RXNE)==SET){test=SPI2_ReadByte(0x00);// test = SPI2_ReadWriteByte(0xaa);}}
在debug模式调试中发现程序一直没有进入中断。利用示波器测试主机发送的sck/cs/mosi信号也没有问题,烦请工程师们帮我看看,谢谢!