我用CH376芯片查询U盘总容量和剩余容量读出来的数据不对，插入32GU盘实际为29.71G，剩余14.19G，但读出来的数据为总扇区0xB6C40009，剩余扇区0xC6684003，插入另外一个32GU盘实际为27.86G，剩余21.44G，读出来的数据为总扇区0x7BD14009，剩余扇区0x63622003，文件系统都是FAT32；请教各位大神，帮我看下是哪里的问题，下面是我查询容量的代码

void?QueryDiskSize(BYTE?mDiskNAme)
void QueryDiskSize(BYTE mDiskNAme)
{
	BYTE mData0,mData1,mData2,mData3;
	LONG mTimer;
	mTimer=0;
	CH376->mCH376CMD=DISK_QUERY;//<<8;
	DelayUs(2);
	while(INT_CH376==1){mTimer=mTimer+1;if(mTimer>5000000)return;}
	mData0=CH376GetIntStatus();
	if(mData0==USB_INT_SUCCESS)
	{
		CH376->mCH376CMD=RD_USB_DATA0;//<<8;
		DelayUs(2);
		//得出总容量
		mData0=CH376->mCH376DAT;//>>8;
		LCDStringData(100,150,"TCap=%H",mData0);
		mData1=CH376->mCH376DAT;//>>8;
		LCDStringData(200,150,"%H",mData1);
		mData2=CH376->mCH376DAT;//>>8;
		LCDStringData(250,150,"%H",mData2);
		mData3=CH376->mCH376DAT;//>>8;
		LCDStringData(300,150,"%H",mData3);
		//mTemp2=mTemp2>>1;//得出总空间大小(以Kb为单位)
		mSysRun.mDisk[mDiskNAme].mTotalCapacity=mData0|((WORD)mData1<<8)|((LONG)mData2<<16)|((LONG)mData3<< 24);//得出扇区数
		//得出可用容量
		mData0=CH376->mCH376DAT;//>>8;
		LCDStringData(100,170,"FCap=%H",mData0);	
		mData1=CH376->mCH376DAT;//>>8;				
		LCDStringData(200,170,"%H",mData1);			
		mData2=CH376->mCH376DAT;//>>8;
		LCDStringData(250,170,"%H",mData2);
		mData3=CH376->mCH376DAT;//>>8;
		LCDStringData(300,170,"%H",mData3);
		//mTemp2=mTemp2>>1;//得出总空间大小(以Kb为单位)
		mSysRun.mDisk[mDiskNAme].mFreeCapacity=mData0|((WORD)mData1<<8)|((LONG)mData2<<16)|((LONG)mData3<< 24);;
		DelayUs(1);
		mSysRun.mDisk[mDiskNAme].mFileSystem=CH376->mCH376DAT;
	}
	else
	{
		mSysRun.mDisk[mDiskNAme].mTotalCapacity=0;
		mSysRun.mDisk[mDiskNAme].mFreeCapacity=0;
		mSysRun.mDisk[mDiskNAme].mFileSystem=0;
	}
	SMatchingStringData("TotalCapacity=%H\r\n",mSysRun.mDisk[mDiskNAme].mTotalCapacity);
	SMatchingStringData("mFreeCapacity=%H\r\n",mSysRun.mDisk[mDiskNAme].mFreeCapacity);
	SMatchingStringData("mFileSystem=%H\r\n",mSysRun.mDisk[mDiskNAme].mFileSystem);
}

您好，您联系xcc@wch.cn邮箱直接发您一份查询容量的代码试下， 另外计算方式为 32位数据*512/1024/1024/1024=XXGB