flash.c

来自「51单片机用c语言实例 包括ad」· C语言 代码 · 共 85 行

/******************************************************/
/*    文件名: Flash.c                                 */
/*    功能描述: 编程扩展AT29C010, 了解Flash特性       */
/******************************************************/

#define START_ADDR     ((unsigned char volatile xdata *) 0x0000)
#define ADDR_UNLOCK1   ((unsigned char volatile xdata *) 0x5555)
#define ADDR_UNLOCK2   ((unsigned char volatile xdata *) 0x2AAA)

sfr AUXR  = 0x8E;

void delay()
{
	unsigned int i;
	for(i=0; i<1000; i++);
}

void unprotect()				// 取消软件数据保护
{
	*ADDR_UNLOCK1 = 0xAA;
	*ADDR_UNLOCK2 = 0x55;
	*ADDR_UNLOCK1 = 0x80;
	*ADDR_UNLOCK1 = 0xAA;
	*ADDR_UNLOCK2 = 0x55;
	*ADDR_UNLOCK1 = 0x20;
}

void erase()					// 芯片擦除
{
	*ADDR_UNLOCK1 = 0xAA;
	*ADDR_UNLOCK2 = 0x55;
	*ADDR_UNLOCK1 = 0x80;
	*ADDR_UNLOCK1 = 0xAA;
	*ADDR_UNLOCK2 = 0x55;
	*ADDR_UNLOCK1 = 0x10;
}

void unp_write()				// 无保护写
{
	unsigned int i;
	unsigned char *Des;
	Des = START_ADDR;
	for(i=0; i<128; i++)
	{
		*Des = 0x55;			//全部写0x55
		Des++;
	}
}

void p_write()					// 带保护写
{
	unsigned int i;
	unsigned char *Des;
	Des = START_ADDR;
	*ADDR_UNLOCK1 = 0xAA;
	*ADDR_UNLOCK2 = 0x55;
	*ADDR_UNLOCK1 = 0xA0;
	for(i=0; i<128; i++)		//写0～128到Flash
	{
		*Des = i;
		Des++;
	}
}

void main()
{
	AUXR = 0x2;

	p_write();		// 带保护写
	delay();

	unp_write();	// 不带保护写
	delay();

	unprotect();	// 去除保护
	unp_write();		
	delay();

	erase();		// 擦除	

	while(1);
}