stm32f103,usb读取sd卡速度慢得问题

2019-03-23 20:14发布

USB端点0为控制模式,端点1批量发送,端点2为批量接受,枚举正常,可以读写,问题在于读写的速度太慢了,1M的文件需要20s。请高手帮忙

usb_endp.c中


void EP2_OUT_Callback(void)
{
  Mass_Storage_Out();
}

usb_bot.c中

void Mass_Storage_Out (void) //对电脑来说,是out,主要是对批量传输中用到的CBW命令封装包的一些解析
{
  u8 CMD;
  CMD = CBW.CB[0];
  Data_Len = GetEPRxCount(ENDP2);

  PMAToUserBufferCopy(Bulk_Data_Buff, ENDP2_RXADDR, Data_Len);// CBW才31个字节,而ENDP2的Count有64个字节

  switch (Bot_State) //Bot_State
  {
    case BOT_IDLE: //IDLE为空闲的意思
      CBW_Decode();
      break;
    case BOT_DATA_OUT:
      if (CMD == SCSI_WRITE10)
      {
        SCSI_Write10_Cmd();
        break;
      }
      Bot_Abort(DIR_OUT);
      Set_Scsi_Sense_Data(ILLEGAL_REQUEST, INVALID_FIELED_IN_COMMAND);
      Set_CSW (CSW_PHASE_ERROR, SEND_CSW_DISABLE);
      break;
    default:
      Bot_Abort(BOTH_DIR);
      Set_Scsi_Sense_Data(ILLEGAL_REQUEST, INVALID_FIELED_IN_COMMAND);
      Set_CSW (CSW_PHASE_ERROR, SEND_CSW_DISABLE);
      break;
  }
}



void CBW_Decode(void)  
{
  u32 Counter;

  for (Counter = 0; Counter < Data_Len; Counter++) //取出CBW包
  {
    *((u8 *)&CBW + Counter) = Bulk_Data_Buff[Counter];
  }
  CSW.dTag = CBW.dTag;
  CSW.dDataResidue = CBW.dDataLength;
  if (Data_Len != BOT_CBW_PACKET_LENGTH) //CBW包的长度是否等于31个字节
  {
    Bot_Abort(BOTH_DIR);
    /* reset the CBW.dSignature to desible the clear feature until receiving a Mass storage reset*/
    CBW.dSignature = 0;
    Set_Scsi_Sense_Data(ILLEGAL_REQUEST, PARAMETER_LIST_LENGTH_ERROR);
    Set_CSW (CSW_CMD_FAILED, SEND_CSW_DISABLE);
    return;
  }

  if (CBW.dSignature == BOT_CBW_SIGNATURE) //判断CBW签名
  {
    /* Valid CBW */
    if ((CBW.bLUN != 0) || (CBW.bCBLength < 1) || (CBW.bCBLength > 16))
//判断逻辑地址,和数据长度
    {
      Bot_Abort(BOTH_DIR);
      Set_Scsi_Sense_Data(ILLEGAL_REQUEST, INVALID_FIELED_IN_COMMAND);
      Set_CSW (CSW_CMD_FAILED, SEND_CSW_DISABLE);
    }
    else
    {
      switch (CBW.CB[0])   //分类处理CBW包中的命令。
      {
        case SCSI_REQUEST_SENSE:
          SCSI_RequestSense_Cmd ();
          break;
        case SCSI_INQUIRY:
          SCSI_Inquiry_Cmd();
          break;
        case SCSI_START_STOP_UNIT:
          SCSI_Start_Stop_Unit_Cmd();
        case SCSI_ALLOW_MEDIUM_REMOVAL:
          SCSI_Start_Stop_Unit_Cmd();
          break;
        case SCSI_MODE_SENSE6:
          SCSI_ModeSense6_Cmd ();
          break;
        case SCSI_MODE_SENSE10:
          SCSI_ModeSense10_Cmd ();
          break;
        case SCSI_READ_FORMAT_CAPACITIES:
          SCSI_ReadFormatCapacity_Cmd();
          break;
        case SCSI_READ_CAPACITY10:
          SCSI_ReadCapacity10_Cmd();
          break;
        case SCSI_TEST_UNIT_READY:
          SCSI_TestUnitReady_Cmd();
          break;
        case SCSI_READ10:
          SCSI_Read10_Cmd();  //READ(10)命令用来读取实际的磁盘数据,操作码为0x28
          break;
        case SCSI_WRITE10:
          SCSI_Write10_Cmd();
          break;
        case SCSI_VERIFY10:
          SCSI_Verify10_Cmd();
          break;
          /*Unsupported command*/

        case SCSI_MODE_SELECT10:
          SCSI_Mode_Select10_Cmd();
          break;
        case SCSI_MODE_SELECT6:
          SCSI_Mode_Select6_Cmd();
          break;
        case SCSI_FORMAT_UNIT:
          SCSI_FormatUnit_Cmd();
          break;
        case SCSI_SEND_DIAGNOSTIC:
          SCSI_Send_Diagnostic_Cmd();
          break;
        case SCSI_READ6:
          SCSI_Read6_Cmd();
          break;
        case SCSI_READ12:
          SCSI_Read12_Cmd();
          break;
        case SCSI_READ16:
          SCSI_Read16_Cmd();
          break;
        case SCSI_READ_CAPACITY16:
          SCSI_READ_CAPACITY16_Cmd();
          break;
        case SCSI_WRITE6:
          SCSI_Write6_Cmd();
          break;
        case SCSI_WRITE12:
          SCSI_Write12_Cmd();
          break;
        case SCSI_WRITE16:
          SCSI_Write16_Cmd();
          break;
        case SCSI_VERIFY12:
          SCSI_Verify12_Cmd();
          break;
        case SCSI_VERIFY16:
          SCSI_Verify16_Cmd();
          break;

        default:
        {
          Bot_Abort(BOTH_DIR);
          Set_Scsi_Sense_Data(ILLEGAL_REQUEST, INVALID_COMMAND);
          Set_CSW (CSW_CMD_FAILED, SEND_CSW_DISABLE);
        }
      }
    }
  }
  else
  {
    /* Invalid CBW */
    Bot_Abort(BOTH_DIR);
    Set_Scsi_Sense_Data(ILLEGAL_REQUEST, INVALID_COMMAND);
    Set_CSW (CSW_CMD_FAILED, SEND_CSW_DISABLE);
  }
} 此帖出自小平头技术问答
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