//-------------------------------------------------------------------------
/*FAT16.C?-?LINO?TECH
??Designed?by?Carter
??2008-03-19
*/

#include?	

#include	“FAT16.h“
#include	“sd.h“
//------------------------------------------------------------------------
#define	SEC_Size				512
#define	MBR_Sector				0				//絕對地址
#define	FAT_Sector				0				//邏輯地址
//-------------------------------------------------------------------------
uint8_t		BUFFER[SEC_Size];
uint8_t		PB_RelativeSector;
uint16_t	BPB_BytesPerSec;
uint8_t		BPB_SecPerClus;
uint16_t	BPB_RsvdSecCnt;
uint8_t		BPB_NumFATs;
uint16_t	BPB_RootEntCnt;
uint16_t	BPB_TotSec16;
uint16_t	BPB_FATSz16;							//FAT占用的sectors
uint32_t	BPB_HiddSec;
//-------------------------------------------------------------------------
uint8_t?ReadSector（uint32_t?sector?uint8_t*?buffer?）
{
????int8?stat;
????
????hwInterface?sdNow;??
????sdNow.sectorCount?=?1;
????stat?=?sd_readSector（&sdNowsectorbuffer512）;
????
????if（stat==0）
????{
????????return?SD_SUCC;
????}
????else
????{
????????return?SD_FAIL;
????};
}
uint8_t?WriteSector（uint32_t?sector?uint8_t*?buffer）
{
????hwInterface?sdNow;??
????sdNow.sectorCount?=?1;
????sd_writeSector（&sdNowsectorbuffer）;
????
????return?0;
}

uint8_t?ReadBlock（uint32_t?LBA）{					//絕對地址讀一個扇區
	if（ReadSector（LBABUFFER）!=0）return?SD_FAIL;
	return?SD_SUCC;
}
//-------------------------------------------------------------------------
uint8_t?WriteBlock（uint32_t?LBA）{					//絕對地址寫一個扇區
	if（WriteSector（LBABUFFER）!=0）return?SD_FAIL;
	return?SD_SUCC;
}
//-------------------------------------------------------------------------
uint8_t?ReadFatBlock（uint32_t?Add）{					//邏輯地址讀一個扇區
//	return?ReadBlock（Add+PB_RelativeSector）;??//for?HardDisk
??	return?ReadBlock（Add+BPB_HiddSec）;
}
//-------------------------------------------------------------------------
uint8_t?WriteFatBlock（uint32_t?Add）{				//邏輯地址寫一個扇區
//	return?WriteBlock（Add+PB_RelativeSector）;??//for?HardDisk
????return?WriteBlock（Add+BPB_HiddSec）;
}
//-------------------------------------------------------------------------
void?CopyBytes（uint8_t?*psuint8_t?*pduint16_t?size）{	//內存拷貝
	for（;size;size--）*pd++=*ps++;
}
//-------------------------------------------------------------------------
uint8_t?IsEqual（uint8_t?*pauint8_t?*pbuint8_t?size）{	//內存比較
	for（;size;size--）if（*pa++!=*pb++）return?0;
	return?1;
}
//-------------------------------------------------------------------------
void?EmptyBytes（uint8_t?*pduint16_t?size）{			//內存清空
	for（;size;size--）*pd++?=0;
}
//-------------------------------------------------------------------------
uint8_t?ReadMBR（void）{									//讀取MBR數據結構
	uint8_t?ok;
	FAT_MBR?*?MBR=（FAT_MBR*）BUFFER;
	ok=ReadBlock（MBR_Sector）;
	if（ok==SD_FAIL）return?SD_FAIL;
	if（MBR->MBR_Signature!=0xAA55）return?SD_FAIL;		//讀有效標志
		
	//獲取參數
	PB_RelativeSector=MBR->MBR_pb[0].PB_RelativeSector;//讀邏輯地址與絕對地址的偏移
	return?SD_SUCC;
}