flash.c

用89C51SND1C实现MP3播放器的源代码.用KEIL c51编写.

#include <stdio.h>
#include <stdlib.h>
#include <string.h>


#include <REGSND1.H>
#include "flash.h"
#include "uart.h"

xdata BYTE rKM29UXDATA  	_at_	0x4000;

extern unsigned char databuff[SectorLength];

long int Current_Cluster,DataRead=0,DataRemain=0;
unsigned short FAT_Table[SectorLength];

unsigned int Check_Flash_Id(void)
{
	int i;
	unsigned int id;

	FC_CMD;
	rKM29UXDATA = 0x90;

	FC_ADDR;
	rKM29UXDATA = 0;
	FC_DATA;

	for(i=0;i<5;i++);	//wait 100ns
	id = rKM29UXDATA<<8;
	for(i=0;i<5;i++);	//wait 100ns
	id += rKM29UXDATA;
	FC_INACTIVE;
	return id;
}
void Flash_Reset()		//flash reset
{ 
	int i;
	//  rPDATC = rPDATC | WP;	//write unprotect
	FC_CMD;
	rKM29UXDATA = 0xff;	//reset command
	for (i=0;i<3000;i++);	//delay 	
}
/********************************************************/
/*功能：擦除FLASH的1Block(对应文件系统为1Cluster)          */
/*     每一个簇为16KB，因此KM29U128共有1024个簇            */
/*输入：unsigned int cluster/block(需要擦除的Block Number)*/
/*返回：OK或FAIL                                         */
/********************************************************/

unsigned char Erase_Cluster(unsigned int cluster) 
{
	unsigned int blockPage = (cluster<<5);

	FC_CMD;
	rKM29UXDATA = 0x60;

	FC_ADDR;	     
	rKM29UXDATA = blockPage & 0xff;  
	rKM29UXDATA = (blockPage>>8) & 0xff;

//	for(i=0;i<2;i++);		//tWC  50ns
    
	FC_CMD;
	rKM29UXDATA = 0xd0;
    
//	for(i=0;i<3;i++);
    
	FC_DATA;
	WAITRB;					//wait max 3ms

	FC_CMD;
	rKM29UXDATA = 0x70;
	FC_DATA;
	if (rKM29UXDATA & 0x1) //erase error
	{
		FC_INACTIVE;
		return FALSE;
	}
	else 
	{
		FC_INACTIVE;   
		return TRUE;
	}
}

/********************************************************/

int VerifyPage(unsigned int block,unsigned int page,unsigned char *buffer)
{
	ReadPage(block,page,databuff);
	if(strncmp((char *)databuff,(char *)buffer,528)==0)
		return 1;
	else
		return 0;
}

/*****************************************************************/
/*功能：读取FLASH的某个Block中的1page数据                           */
/*     在文件系统中，有如下对应关系：Block=Cluster                   */
/*                               Page =Sector                    */
/*输入：unsigned int block,page,unsigned char *pPage(存放数据的地址)*/
/*****************************************************************/

void ReadPage(unsigned int block,unsigned int page,unsigned char *pPage)
{
	int i=512;
	unsigned int blockPage = (block<<5) + page;

	FC_CMD;               
	rKM29UXDATA = 0x00;
	FC_ADDR;
	rKM29UXDATA = 0;
	rKM29UXDATA = blockPage & 0xff;
	rKM29UXDATA = (blockPage>>8) & 0xff;
//	for(i=0;i<3;i++);
	FC_DATA;
	WAITRB;	//random access ,wait max. 10us 
//	__RdPage528(pPage);		//which is written with assemble in flash.s
	while(i--) {*pPage++=rKM29UXDATA;}
	FC_INACTIVE;
}

/*****************************************************************/
/*功能：向FLASH的某个Block中的1page写入数据                         */
/*     在文件系统中，有如下对应关系：Block=Cluster                   */
/*                               Page =Sector                    */
/*输入：unsigned int block,page,unsigned char *pPage(存放数据的地址)*/
/*输出：0:Fail;1:OK                                               */
/*****************************************************************/

int WritePage(unsigned int block,unsigned int page,unsigned char *pPage)  
{
	int i=512;
	unsigned int blockPage = (block<<5) + page;
//	unsigned char *Source;                                      //the begin addr of data to write
//	Source=pPage;
	FC_CMD;
	rKM29UXDATA = 0x80;
	FC_ADDR;
	rKM29UXDATA = 0;
	rKM29UXDATA = blockPage & 0xff;
	rKM29UXDATA = (blockPage>>8) & 0xff;
	FC_DATA;
	while(i--)
		{rKM29UXDATA=*pPage++;}         //data input->as the same as _WrPage528()
//	__WrPage528(pPage); //which is written with assemble in flash.s

	FC_CMD;
	rKM29UXDATA = 0x10;
//	for(i=0;i<10;i++);  //twb=100ns. why is it 10? spec is false?  
                        //No. It's because of LED of PE1.
	WAITRB;	//wait max 500us;
	rKM29UXDATA = 0x70;
	FC_DATA;
//	for(i=0;i<3;i++);  //twhr=60ns
	if((rKM29UXDATA & 0x1))	//		
	{
		FC_INACTIVE;	
		return 0;
	}
	else
	{
		FC_INACTIVE;	    
		#if (WRITEVERIFY==1)
			return VerifyPage(block,page,pPage);	
		#else
			return 1;
		#endif
	}
}