例程将256个字节的数据写入25Q64，然后在读取出来，比较两组数据是否一致。如一致则串口打印提示测试成功。否则测试失败。
代码相对复杂，首先需要初始化DMA，分别将SPI数据的读取和写入指向不同的DMA通道。

DMA的初始化

void SPI2_DMA_RX_Init()
{
    DMA_InitTypeDef  DMA_InitStructure;
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);  //ʹÄÜDMA´«Êä
    DMA_DeInit(DMA1_Channel4);
    DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t) & (SPI2->RXREG); //SPI½ÓÊÕÊý¾Ý¼Ä´æÆ÷
    DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)rxdata; //SPI½ÓÊÕµ½µÄÊý¾Ý´æ·Å»ùµØÖ·
    DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;//Êý¾Ý´ÓÍâÉèµ½memory
    DMA_InitStructure.DMA_BufferSize = 20;
    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_Channel4, &DMA_InitStructure);//SPI2 RXΪDMAͨµÀ4
}
void SPI2_DMA_TX_Init()
{
    DMA_InitTypeDef  DMA_InitStructure;
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);  //ʹÄÜDMA´«Êä
    DMA_DeInit(DMA1_Channel5);
    DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t) & (SPI2->TXREG); //SPI·¢ËÍÊý¾Ý¼Ä´æÆ÷
    DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)txdata;
    DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;//Êý¾Ý´Ómemoryµ½ÍâÉè
    DMA_InitStructure.DMA_BufferSize = 8;//·¢ËÍÊý¾Ý¸öÊý
    DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;//ÍâÉèµØÖ·²»¸Ä±ä
    DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;//memoryµØÖ·µÝÔö¿ªÆô
    DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
    DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
    DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;//ÆÕͨģʽ
    DMA_InitStructure.DMA_Priority = DMA_Priority_VeryHigh;
    DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
    DMA_Init(DMA1_Channel5, &DMA_InitStructure);//SPI RXΪDMAͨµÀ5
}

25q64的读写接口函数

具体需要查看25q64的规格书，了解内部指令和数据存储的结构。

void SPI25xx_PageRead(unsigned long address, unsigned char *p, unsigned int number)
{


    unsigned char temp[5];
    unsigned int i = 0;

    address = address & 0xffff0000;
    temp[i++] = READ;
    temp[i++] = ((unsigned char)(address >> 16)) & 0xff;
    temp[i++] = ((unsigned char)(address >> 8)) & 0xff;
    temp[i++] = ((unsigned char)address) & 0xff;
    SPI25xx_checkStatus();
    /*Spi cs assign to this pin,select*/
    SPIM_CSLow(SPI2);
    spiWriteBurst(temp, i);
    spiReadBurst(p, number);

    /*Spi cs release*/
    SPIM_CSHigh(SPI2);
}
void SPI25xx_PageProgram(unsigned long address, unsigned char *p, unsigned int number)
{
    unsigned char temp[5];
    unsigned int i = 0;

    address = address & 0xffff0000;
    temp[i++] = PP;
    temp[i++] = ((unsigned char)(address >> 16)) & 0xff;
    temp[i++] = ((unsigned char)(address >> 8)) & 0xff;
    temp[i++] = ((unsigned char)address) & 0xff;
    SPI25xx_WriteEnable();
    /*Spi cs assign to this pin,select*/
    SPIM_CSLow(SPI2);
    spiWriteBurst(temp, i);
    spiWriteBurst(p, number);

    /*Spi cs release*/
    SPIM_CSHigh(SPI2);
    SPI25xx_checkStatus();
}

验证测试25q16程序

void SPI_TxRx_25xx_DMAPOLLing_Test(void)
{
    unsigned int i, result = 0;
    for(i = 0; i < 256; i++) {
        tmpdata[i] = i * 2;
    }
    {
        UartSendGroup((u8*)printBuf, sprintf(printBuf, "SPI2 test\r\n"));
        SPI25xxPolling_Init();
        //while(1)
        {
                    UartSendGroup((u8*)printBuf, sprintf(printBuf, "SPI25xx_ReadID()\r\n"));
            SPI25xx_ReadID();
        }
        //return;
                UartSendGroup((u8*)printBuf, sprintf(printBuf, "SPI25xx_SectorErase(0)\r\n"));
        SPI25xx_SectorErase(0);
                UartSendGroup((u8*)printBuf, sprintf(printBuf, "SPI25xx_PageProgram(0, tmpdata, 256)\r\n"));
        SPI25xx_PageProgram(0, tmpdata, 256);


        memset(rxtmpdata, 0x0, 256);

        /*��д��ȥ��һҳ256�ֽڶ�����*/
                UartSendGroup((u8*)printBuf, sprintf(printBuf, "SPI25xx_PageRead(0, rxtmpdata, 256)\r\n"));
        SPI25xx_PageRead(0, rxtmpdata, 256);


        for(i = 0; i < 10; i++) {
            UartSendGroup((u8*)printBuf, sprintf(printBuf, "rx[%d]=0x%x\r\n", i, rxtmpdata[i]));
        }
        for(i = 0; i < 256; i++) {
            if(tmpdata[i] != rxtmpdata[i]) {
                result = 1;
                break;
            }

        }
        if(result == 1) {
            UartSendGroup((u8*)printBuf, sprintf(printBuf, "SPI2 WR 25xx Fail\r\n"));
        } else {
            UartSendGroup((u8*)printBuf, sprintf(printBuf, "SPI2 WR 25xx Successful\r\n"));

        }
        UartSendGroup((u8*)printBuf, sprintf(printBuf, "SPI2 test over\r\n"));
    }

}

测试结果

通过串口会打印测试流程和最终的测试结果。通过串口助手可以收到以下信息：

Start SPI test
SPI2 test
SPI25xx_ReadID()
SPI25xx_ReadID:ef 40 17
SPI25xx_SectorErase(0)
SPI25xx_checkStatus:0
SPI25xx_checkStatus:3
SPI25xx_checkStatus:3
SPI25xx_checkStatus:3
SPI25xx_checkStatus:3
SPI25xx_checkStatus:3
SPI25xx_PageProgram(0, tmpdata, 256)
SPI25xx_checkStatus:0
SPI25xx_checkStatus:3
SPI25xx_PageRead(0, rxtmpdata, 256)
SPI25xx_checkStatus:0
rx[0]=0x0
rx[1]=0x2
rx[2]=0x4
rx[3]=0x6
rx[4]=0x8
rx[5]=0xa
rx[6]=0xc
rx[7]=0xe
rx[8]=0x10
rx[9]=0x12
SPI2 WR 25xx Successful
SPI2 test over