stm32f4 - FATFS与定时器中断STM32f407VG冲突

Question

*嗨，我目前正在从事一个需要读取 3 个 ADC 值、日期和时间的项目。这些值使用 FATFS 存储在 SD 卡中的 .txt 文件中。以 1000Hz 的频率进行读数非常重要。.txt 文件如下所示：

2021;07;01;00;36;37;0010;0.583;-0.416;-0.765;
2021;07;01;00;36;37;0023;0.577;-0.422;-0.779;
2021;07;01;00;36;37;0032;0.567;-0.416;-0.752;
2021;07;01;00;36;37;0043;0.583;-0.430;-0.776;
2021;07;01;00;36;37;0052;0.567;-0.438;-0.776;

因此，我知道执行 f_write 和 f_sync 函数所需的时间是可变的，我决定使用定时器中断来读取 ADC 值并将它们存储在缓冲区中（我实际上使用 2 个缓冲区，稍后将讨论），同时使用主循环将数据写入txt文件。我正在尝试以下似乎与 f_write 函数一致的问题：

2000;07;01;00;50;27;4559;0.717;-0.309;-0.682;
2000;07;01;00;50;27;4569;0.717;-0.320;-0.704;
2000;07;01;00;50;27;4579;79;0.709;-0.314;-0.701;
2000;07;01;00;50;27;4589;0.709;-0.322;-0.706;
2000;07;01;00;50;27;4599;0.701;-0.314;-0.706;

错误在上面的第三行。似乎每次我填充缓冲区并调用 f_write 函数时，我都会重复或丢失多达 3 个字符。如果我调试代码，似乎缓冲区是正确的。所以我猜问题出在 f_write 函数被定时器中断停止。有任何想法吗？

ps：我使用2个缓冲区来存储数据，这样当其中一个被复制到txt文件时，另一个正在接收数据。

/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
    /* If flag is set, write data to SD card */
    if(myData.flagPrint2SdCard == 1)
    {
        /* Write data to SDCARD */
        if(myData.flagCurrentDataBuffer == 2)
        {
            UINT bytesWritten=0;
            f_write(&SDFile,myData.dataBuffer_1,strlen(myData.dataBuffer_1),bytesWritten);
        }
        else if (myData.flagCurrentDataBuffer == 1)
        {
            UINT bytesWritten=0;
            f_write(&SDFile,myData.dataBuffer_2,strlen(myData.dataBuffer_2),bytesWritten);
        }
        /* Sync FATFS */
        fatRes = f_sync(&SDFile);
        /* Reset print to sd card flag */
        myData.flagPrint2SdCard = 0;
    }
}

void TIM3_IRQHandler(void)
{
/* X values */
ADC_Select_X();
HAL_ADC_Start(&hadc1);
HAL_ADC_PollForConversion(&hadc1,100);
myData.digX = (float)HAL_ADC_GetValue(&hadc1) - (float)2048;
HAL_ADC_Stop(&hadc1);
myData.gX = (myData.digX*myData.voltsPerDigit)/ myData.senX;

/* Y values */
ADC_Select_Y();
HAL_ADC_Start(&hadc1);
HAL_ADC_PollForConversion(&hadc1,100);
myData.digY = (float)HAL_ADC_GetValue(&hadc1) - (float)2048;
HAL_ADC_Stop(&hadc1);
myData.gY = (myData.digY*myData.voltsPerDigit)/ myData.senY;

/* Z values */
ADC_Select_Z();
HAL_ADC_Start(&hadc1);
HAL_ADC_PollForConversion(&hadc1,100);
myData.digZ = (float)HAL_ADC_GetValue(&hadc1) - (float)2048;
HAL_ADC_Stop(&hadc1);
myData.gZ = (myData.digZ*myData.voltsPerDigit)/ myData.senZ;

/* Date and time values */
HAL_RTC_GetTime(&hrtc,&rtcTime,RTC_FORMAT_BIN);
HAL_RTC_GetDate(&hrtc,&rtcDate,RTC_FORMAT_BIN);
//  subSec

if(myData.flagCurrentDataBuffer == 1)
{
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_1[myData.pointerDataBuffer], "20%02u;", rtcDate.Year);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_1[myData.pointerDataBuffer], "%02u;", rtcDate.Month);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_1[myData.pointerDataBuffer], "%02u;", rtcDate.Date);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_1[myData.pointerDataBuffer], "%02u;", rtcTime.Hours);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_1[myData.pointerDataBuffer], "%02u;", rtcTime.Minutes);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_1[myData.pointerDataBuffer], "%02u;", rtcTime.Seconds);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_1[myData.pointerDataBuffer], "%04u;", (uint32_t)(-0.609815651324625*(float)rtcTime.SubSeconds+(float)9999));
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_1[myData.pointerDataBuffer], "%.3f;", myData.gX);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_1[myData.pointerDataBuffer], "%.3f;", myData.gY);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_1[myData.pointerDataBuffer], "%.3f;", myData.gZ);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_1[myData.pointerDataBuffer], "\r\n");
}
else if(myData.flagCurrentDataBuffer == 2)
{
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_2[myData.pointerDataBuffer], "20%02u;", rtcDate.Year);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_2[myData.pointerDataBuffer], "%02u;", rtcDate.Month);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_2[myData.pointerDataBuffer], "%02u;", rtcDate.Date);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_2[myData.pointerDataBuffer], "%02u;", rtcTime.Hours);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_2[myData.pointerDataBuffer], "%02u;", rtcTime.Minutes);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_2[myData.pointerDataBuffer], "%02u;", rtcTime.Seconds);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_2[myData.pointerDataBuffer], "%04u;", (uint32_t)(-0.609815651324625*(float)rtcTime.SubSeconds+(float)9999)); ;
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_2[myData.pointerDataBuffer], "%.3f;", myData.gX);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_2[myData.pointerDataBuffer], "%.3f;", myData.gY);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_2[myData.pointerDataBuffer], "%.3f;", myData.gZ);
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_2[myData.pointerDataBuffer], "\r\n");
}

if(myData.dataCounter >= 450)
{
    /* Switch buffers */
    SwitchBuffers();

    myData.dataCounter = 0;

    /* Set flag to write data to SD card */
    myData.flagPrint2SdCard = 1;
}
else
{
    myData.dataCounter++;
}

/* Interruption handler */
HAL_TIM_IRQHandler(&htim3);
}

void SwitchBuffers(void)
{
/* Switch buffer flag switched */
if(myData.flagCurrentDataBuffer == 1)
{
    /* Add string terminator to buffer */
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_1[myData.pointerDataBuffer], "\0");
    myData.flagCurrentDataBuffer = 2;
}
else if(myData.flagCurrentDataBuffer == 2)
{
    /* Add string terminator to buffer */
    myData.pointerDataBuffer += sprintf(&myData.dataBuffer_2[myData.pointerDataBuffer], "\0");
    myData.flagCurrentDataBuffer = 1;
}

/* Reset pointer data buffer */
myData.pointerDataBuffer = 0;
}

标签： stm32f4fatfs