STM32F103，从机spi，主机后开机就出现错误

yqzhang

问题现象：
STM32F103（本机）作为从机接收spi，通过DMA读取数据，
如果本机后开机，主机（上位机,FPGA）先开机，则通信正常。
如果本机先开机，再开主机，则通信不正常，接收到的数据会出现错位。此时如果“本机”再重启，则通信正常。

源程序如下，希望热心大神帮忙看看。
void SPI_Config(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
SPI_InitTypeDef  SPI_InitStructure;

RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOB, ENABLE );
RCC_APB1PeriphClockCmd( RCC_APB1Periph_SPI2,  ENABLE );
RCC_APB2PeriphClockCmd( RCC_APB2Periph_AFIO,  ENABLE );       
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
       
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_14;                     //MISO
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;  
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12|GPIO_Pin_13| GPIO_Pin_15;      //SCK MOSI NSS
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;  
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
//GPIO_SetBits(GPIOB,GPIO_Pin_13|GPIO_Pin_14|GPIO_Pin_15);  //PB13/14/15上拉

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_Hard;
SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_64;
SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
SPI_InitStructure.SPI_CRCPolynomial = 7;
SPI_Init(SPI2, &SPI_InitStructure);  

  SPI_SSOutputCmd(SPI2, ENABLE);
        SPI_I2S_DMACmd(SPI2, SPI_I2S_DMAReq_Rx, ENABLE);
        SPI_I2S_DMACmd(SPI2, SPI_I2S_DMAReq_Tx, ENABLE);
  SPI_Cmd(SPI2, ENABLE);
}

void DMA_Configuration(void)
{

        DMA_InitTypeDef DMA_InitStructure;
        //????DMA,?????
        /* fill init structure */
        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_DeInit(DMA1_Channel4);
        DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)(&SPI2->DR);
        DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
        DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)rx_buf;
        DMA_InitStructure.DMA_BufferSize = 128;
        DMA_Init(DMA1_Channel4, &DMA_InitStructure);   //sp1 2 3  sp2 4 5
        DMA_Cmd(DMA1_Channel4, DISABLE);
        DMA_Cmd(DMA1_Channel4, ENABLE);

       
        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_DeInit(DMA1_Channel5);
        DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)(&SPI2->DR);
        DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
        DMA_InitStructure.DMA_MemoryBaseAddr = 0;
        DMA_InitStructure.DMA_BufferSize = 1;
        DMA_Init(DMA1_Channel5, &DMA_InitStructure);
       

}

void NVIC_Config(void)
{
        NVIC_InitTypeDef NVIC_InitStructure;
        EXTI_InitTypeDef EXTI_InitStruct;
               
        NVIC_InitStructure.NVIC_IRQChannel =EXTI15_10_IRQn;
        NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
        NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
        NVIC_Init(&NVIC_InitStructure);       

        GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource12);
        EXTI_InitStruct.EXTI_Line = EXTI_Line12;
        EXTI_InitStruct.EXTI_Mode = EXTI_Mode_Interrupt;
        EXTI_InitStruct.EXTI_Trigger = EXTI_Trigger_Rising;
        EXTI_InitStruct.EXTI_LineCmd = ENABLE;
        EXTI_Init(&EXTI_InitStruct);
       
  DMA_Configuration();
}


//以下是数据处理
void EXTI15_10_IRQHandler(void)
{
       
        static uint8_t data[7] = {1,1,0,0,0,1,1};
        int len,i;
        //SPI_Cmd(SPI2, DISABLE);
        //disable DMA
        DMA_Cmd(DMA1_Channel4, DISABLE);
        len = 128 - DMA_GetCurrDataCounter(DMA1_Channel4);
        if(len>=3)
        {
        if(rx_buf[0] >= 0x05 )
                for(i=(rx_buf[0]-0x05);i<(rx_buf[1]+rx_buf[0]-0x05);i++)
          data[i] = rx_buf[i+2-(rx_buf[0]-0x05)];                        
        }
        DMA_SetCurrDataCounter(DMA1_Channel4,128);
        DMA_Cmd(DMA1_Channel4, ENABLE);
        EXTI_ClearITPendingBit(EXTI_Line12);
        GPIO_Set(data[0],data[1],data[2],data[3],data[4],data[5],data[6]);
}

正点原子

看看时序？

三叶草

时序不正确吧，还有就是处理机制