stat = NFRdDat();
		//printf("%x\n", stat);
	}while(!(stat&0x40));
	NFWrCmd(READCMD0);
	return stat&1;
}
#endif

/********************************************************************
Function name: NFReadID
Parameter    : void     
Description	 : 讀取NAND FLASH的ID號
Return		 : 返回讀取的ID號
Argument     :                            
Autor & date : void
*********************************************************************/
static U32 NFReadID(void)
{
	U32 id, loop = 0;

	NFChipEn();
	NFWrCmd(READIDCMD);
	NFWrAddr(0);
	while(NFIsBusy()&&(loop<10000)) loop++;
	if(loop>=10000)
		return 0;
	id  = NFRdDat()<<8;
	id |= NFRdDat();
	NFChipDs();
	
	return id;
}

/********************************************************************
Function name: NFReadStat
Parameter    : void     
Description	 : 讀取NAND FLASH的狀態
Return		 : 返回讀取的狀態
Argument     :                            
Autor & date : void
*********************************************************************/
static U16 NFReadStat(void)
{
	U16 stat;
	
	NFChipEn();	
	NFWrCmd(QUERYCMD);
	stat = NFRdDat();	
	NFChipDs();
	
	return stat;
}


/********************************************************************
Function name: NFEraseBlock
Parameter    : U32 addr : 要擦除塊的地址     
Description	 : 擦除地址為addr的塊
Return		 : void
Argument     :                            
Autor & date : void
*********************************************************************/
static U32 NFEraseBlock(U32 addr)
{
	U8 stat;

	addr &= ~0x1f;
		
	NFChipEn();	
	NFWrCmd(ERASECMD0);		
	NFWrAddr(addr);
	NFWrAddr(addr>>8);
	if(NandAddr)
		NFWrAddr(addr>>16);
	NFWrCmd(ERASECMD1);		
	stat = NFWaitBusy();
	NFChipDs();
	
#ifdef	ER_BAD_BLK_TEST
	if(!((addr+0xe0)&0xff)) stat = 1;	//just for test bad block
#endif
	putch('.');
	return stat;
}

/********************************************************************
Function name: NandReadPage
Parameter    : addr : 地址    *buf:要寫入的數據
Description	 : 向地址addr寫入數據*buf
Return		 : void
Argument     : addr = page address                                   
Autor & date :
*********************************************************************/
static void NFReadPage(U32 addr, U8 *buf)
{
	U16 i;
	
	NFChipEn();
	NFWrCmd(READCMD0);
	NFWrAddr(0);
	NFWrAddr(addr);
	NFWrAddr(addr>>8);
	if(NandAddr)
		NFWrAddr(addr>>16);
//	InitEcc();
	NFWaitBusy();		
	for(i=0; i<512; i++)
		buf[i] = NFRdDat();		
	NFChipDs();
}

/********************************************************************
Function name: NandWritePage
Parameter    : addr : 地址    *buf:要寫入的數據 blk_idx
Description	 : 向地址addr寫入數據*buf
Return		 : void
Argument     : addr = page address                                   
Autor & date :
*********************************************************************/
//addr = page address
static U32 NFWritePage(U32 addr, U8 *buf, U16 blk_idx)
{
	U16 i, stat;
//	U8 tmp[3];
	U8 ecc_code[3];
	U8 oob_info[16];
		
	for(i=0; i<sizeof(oob_info); i++)
		oob_info[i] = 0xff;
	
	nand_calculate_ecc(buf, ecc_code);
	oob_info[eccpos[0]] = ecc_code[0];
	oob_info[eccpos[1]] = ecc_code[1];
	oob_info[eccpos[2]] = ecc_code[2];
	nand_calculate_ecc(buf+256, ecc_code);
	oob_info[eccpos[3]] = ecc_code[0];
	oob_info[eccpos[4]] = ecc_code[1];
	oob_info[eccpos[5]] = ecc_code[2];
	oob_info[BLK_IDXL]  = blk_idx;
	oob_info[BLK_IDXH]  = blk_idx>>8;
	oob_info[FMT_TAG]   = format_tags[addr&0x1f];
	
	NFChipEn();
	NFWrCmd(PROGCMD0);
	NFWrAddr(0);
	NFWrAddr(addr);
	NFWrAddr(addr>>8);
	if(NandAddr)
		NFWrAddr(addr>>16);
//	InitEcc();	
	for(i=0; i<512; i++)
		NFWrDat(buf[i]);
		
	if(!addr) {
		NFWrDat('b');
		NFWrDat('o');
		NFWrDat('o');
		NFWrDat('t');		
	} else {		
		for(i=0; i<sizeof(oob_info); i++)
			NFWrDat(oob_info[i]);
	}
    	
	NFWrCmd(PROGCMD1);
	stat = NFWaitBusy();
	NFChipDs();
	
#ifdef	WR_BAD_BLK_TEST
	if((addr&0xff)==0x17) stat = 1;	//just for test bad block
#endif
	
	if(stat)
		printf("Write nand flash 0x%x fail\n", addr);
	else {	
		U8 RdDat[512];
		
		NFReadPage(addr, RdDat);
		for(i=0; i<512; i++)
			if(RdDat[i]!=buf[i]) {
				printf("Check data at page 0x%x, offset 0x%x fail\n", addr, i);
				stat = 1;
				break;
			}
	}
		
	return stat;	
}

/********************************************************************
Function name: NandFlashInit
Parameter    : void
Description	 : 初始化Nand Flash
Return		 : void
Argument     :                                    
Autor & date :
*********************************************************************/
static U32 nand_id;
void NandFlashInit(void)
{
	int i;	
	
	support = 0;
	nand_id = NFReadID();
	
	for(i=0; NandFlashChip[i].id!=0; i++)
		if(NandFlashChip[i].id==nand_id) {			
			nand_id = i;
			NandFlashSize = NandFlashChip[i].size;
			support  = 1;
			NandAddr = NandFlashSize>SIZE_32M;
			if(!pNandPart[0].size) {
				pNandPart[0].offset = 0;
				pNandPart[0].size   = NandFlashSize;
				pNandPart[1].size   = 0;				
			}			
			return;
		}
	
}

/********************************************************************
Function name: NandFlashStatusRep
Parameter    : void
Description	 : 讀取Nand Flash的相關信息
Return		 : void
Argument     :                                    
Autor & date :
*********************************************************************/
void NandFlashStatusRep(void)
{
	if(support) {
		printf("Nand Flash ID is 0x%x, Size = %dM, Status = 0x%x\n", NandFlashChip[nand_id].id, NandFlashChip[nand_id].size>>20, NFReadStat());
	} else {
		printf("No supported Nand Flash Found!\n");
	}
}

/********************************************************************
Function name: NandFlash_Test
Parameter    : void
Description	 : 用來測試NAND讀寫實驗
Return		 : void
Argument     :                                    
Autor & date :
*********************************************************************/

void NandFlash_Test( void )
{
	U16 m,n ;
	U8 d[640] ;
	
	//擦除NandFlash
  	printf( "\nNand Flash Erase Block!\n\n" ) ;
	for( m = 0 ; m < 0x200 ; m += 0x20 )		NFEraseBlock( m ) ;

	//給要寫入nandflash的數組賦值
	for( m = 0 ; m < 640 ; m++ )	d[m] = m ;
	
	//頁寫方式將數組依次寫入nandflash，一次寫入512字節
   	printf( "\nNand Flash Write Page!\n\n" ) ;
	NFWritePage( 0, d, 0 ) ;

	//將數組全部清零
	for( m = 0 ; m < 640 ; m++ )	d[m] = 0 ;

	//頁讀方式將nandflash的0地址數據讀出并寫到數組
   	printf( "\nNand Flash Read Page!\n\n" ) ;
	NFReadPage( 0, d ) ;

	//將數組里面的數據依次打印出來，驗證寫入與讀出是否相符
    for( m = 0; m < 40; m++ )
    {
		for( n = 0; n < 16; n++ )
		    printf( "%2x ", d[m*16+n] ) ;
		printf("\n");
    }

}
#endif	/* NAND_SUPPORT */