令人极度困惑的指针问题，求大神帮忙看看

发布于 2020-01-11 11:23:55 浏览：1575 订阅该版

* 本帖最后由 朋友，你好 于 2020-1-11 12:08 编辑 *

```void save_data(uint8_t* msg, uint16_t size)
{            
    uint32_t len = 8192;
    uint8_t data[80];
    uint8_t i = 0;
    while(len < 20400)
    {
        nwy_flash_read(len, data, 80);
        rt_thread_delay(1);
        for(i=0; i<77;)
        {
            rt_kprintf("i = %d,data = %x,len = %d<br>",i, data*,len);
            if(*(uint16_t*)(&data*) == 0xdaeb)
            {
                rt_kprintf("data = UPLOAD_DATA_FLAG<br>");
                i += 5+(data[i+3]<<8|data[i+4]);
            }
            else if(*(uint32_t*)(&data*) == 0xffffffff)
            {
                rt_kprintf("data = %x<br>", data*);               
                rt_memset(data, 0, 80);
                *(uint16_t*)data = UPLOAD_DATA_FLAG;
                data[2] = 1;
                data[3] = size>>8;
                data[4] = size;
               
                rt_memcpy(&data[5], msg, size);
                SPI_W25QXX_Write_NoCheck(data, len+i, 5+size);
                return;               
            }
            else
            {
                i++;
            }
                
        }
        len += 80;
    }
    if(len >= 20400)
    {
        *(uint16_t*)data = UPLOAD_DATA_FLAG;
        data[2] = 1;
        data[3] = size>>8;
        data[4] = size;
       
        rt_memcpy(&data[5], msg, size);
        nwy_flash_write(FLASH_UPLOAD_DATA_ADDR, data, 5+size);
        rt_memset(data, 0xff, 1);
        nwy_flash_write(FLASH_UPLOAD_DATA_ADDR+4096, data, 1);
        nwy_flash_write(FLASH_UPLOAD_DATA_ADDR+8192, data, 1);
    }     
}```

运行结果如下：

i = 0,data = eb,len = 8192
data = UPLOAD_DATA_FLAG
i = 48,data = eb,len = 8192
data = UPLOAD_DATA_FLAG
i = 0,data = 0,len = 8272
psr: 0x01000000
 pc: 0x08013d24
 lr: 0x08017c47
r12: 0x00000000
r03: 0x08013ce3
r02: 0x40013800
r01: 0x00000000
r00: 0x2000564f
hard fault on thread: UploadData
thread                           pri  status      sp     stack size max used left tick  error
-------------------------------- ---  ------- ---------- ----------  ------  ---------- ---
at_clnt0                           9  suspend 0x00000098 0x00000600    35%   0x00000005 000
UploadData                        10  running 0x00000164 0x00001400    36%   0x0000000a 000
tshell                            10  suspend 0x0000007c 0x00000800    07%   0x0000000a 000
tidle0                            31  ready   0x00000054 0x00000100    32%   0x00000019 000
timer                              4  suspend 0x0000005c 0x00000180    23%   0x00000009 000

当把程序改成如下形式之后，就没问题了，可以正常运行。

```void save_data(uint8_t* msg, uint16_t size)
{            
    uint32_t len = 8192;
    uint8_t data[80];
    volatile uint8_t i = 0;
    while(len < 20400)
    {
        nwy_flash_read(len, data, 80);
        rt_thread_delay(1);
        for(i=0; i<77;)
        {
//            if(*(uint16_t*)(&data*) == 0xdaeb)
            if((data* == 0xeb) && (data[i+1] == 0xda))
            {
                i += 5+(data[i+3]<<8|data[i+4]);              
            }                                  
//            else if(*(uint32_t*)(&data*) == 0xffffffff)
            else if((data* == 0xff) && (data[i+1] == 0xff) && (data[i+2] == 0xff) && (data[i+3] == 0xff))
            {               
                *(uint16_t*)data = UPLOAD_DATA_FLAG;
                data[2] = 1;
                data[3] = size>>8;
                data[4] = size;
                
                rt_memcpy(&data[5], msg, size);
                SPI_W25QXX_Write_NoCheck(data, len+i, 5+size);
                return;                
            }
            else
            {
                i++;
            }                
        }
        len += 80;
    }
    if(len >= 20400)
    {
        *(uint16_t*)data = UPLOAD_DATA_FLAG;
        data[2] = 1;
        data[3] = size>>8;
        data[4] = size;
       
        rt_memcpy(&data[5], msg, size);
        nwy_flash_write(FLASH_UPLOAD_DATA_ADDR, data, 5+size);
        rt_memset(data, 0xff, 1);
        nwy_flash_write(FLASH_UPLOAD_DATA_ADDR+4096, data, 1);
        nwy_flash_write(FLASH_UPLOAD_DATA_ADDR+8192, data, 1);
    }     
}
```求解。。。