flash.c.svn-base

lwip协议在arm7+uCos系统上的移植

/***************************************************************************
  文件名称：flash.c
  版本号：	1.0
  日期：	2005-12-16
  说明：	搭配flash.h使用，对flash进行擦写
  调用列表：--
  修改历史：--
*****************************************************************************/
#include "semihosting.h"
#include "delay.h"
#include "flash.h"


/****************************************************************************
  函数名称：EraserFlash(int type,int address)
  说明：	擦除Flash
  调用函数：Delay()
  输入参数：type 擦除类型，address擦除地址
  输出参数：0擦除失败，1擦除成功
****************************************************************************/
int EraserFlash(int type,unsigned int address)
{
	volatile int old_s,new_s;
	
	WriteFlash(0x5555,0xaa);
	WriteFlash(0x2aaa,0x55);
	WriteFlash(0x5555,0x80);
	WriteFlash(0x5555,0xaa);
	WriteFlash(0x2aaa,0x55);
	
	Delay(0);//Reset the clock
	
	switch(type)
	{
		case 1:
			WriteFlash(0x5555,0x10);
			Delay(1500);
			break;
		case 2:
			WriteFlash(address,0x50);
			Delay(300);
			break;
		case 3:
			WriteFlash(address,0x30);
			Delay(300);
			break;
		default :
			return 0;
	}
	
	old_s = ReadFlash(0x0);
	new_s = ReadFlash(0x0);
	if((old_s & 0x40) == (new_s & 0x40))
		return 1; 
	else
		return 0;
}


/****************************************************************************
  函数名称：WriteFH(int address,unsigned short data)
  说明：	擦除Flash
  调用函数：
  输入参数：address 写入地址，date 写入数据
  输出参数：0写入失败，1写入成功
****************************************************************************/
int WriteFH(unsigned int address, unsigned short data)
{
	volatile unsigned short old_s,new_s;
	int WriteOver = 1;
	
	if(address > 0xfffff)   //SST39VF160's highest address
		return 0;
		
	WriteFlash(0x5555,0xaa);
	WriteFlash(0x2aaa,0x55);
	WriteFlash(0x5555,0xa0);
	WriteFlash(address,data);
	
	
	old_s = ReadFlash(0x0);
	while(WriteOver)
	{
		new_s = ReadFlash(0x0);
		if((old_s & 0x40) == (new_s & 0x40))
			WriteOver = 0; 
		else
			old_s = new_s;
	}
	
	if(data == ReadFlash(address))
		return 1;
	else
		return 0;
		
}
/****************************************************************************
  函数名称：ReadFID(unsigned short* MID, unsigned short* DID)
  说明：	读取flash的ID
  调用函数：
  输入参数：MID指向manufacturer ID， DID指向device ID
  输出参数：无
****************************************************************************/
void ReadFID(unsigned short* MID, unsigned short* DID)
{
	WriteFlash(0x5555,0xaa);
	WriteFlash(0x2aaa,0x55);
	WriteFlash(0x5555,0x90);
	
	*MID = ReadFlash(0x0);
	*DID = ReadFlash(0x1);
	
	WriteFlash(0x5555,0xaa);
	WriteFlash(0x2aaa,0x55);
	WriteFlash(0x5555,0xf0);
}