memory.c

是电表处理芯片CS5460A的单片机程序,已经经过产品的验证.

#include <reg51.h>
#include <main.h>
#include <memory.h>
#define    PAGE_SIZE       7

//uchar code table_bit[8]={0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80};
extern uchar code table_bit[8];

sbit SCL=P1^6;
sbit SDA=P1^7;

	
void Set_Start_Condition(void)
{	
	SCL=LOW;
	Delay();	
	SDA=HIGH;
	Delay();
	SCL=HIGH;
	Delay();
	SDA=LOW;
}


void Set_Stop_Condition(void)
{
	SCL=LOW;
	Delay();
	SDA=LOW;
	Delay();
	SCL=HIGH;
	Delay();
	SDA=HIGH;
}


void Send_Byte_Memory(uchar  value)
{
   	uchar  i;
   	for(i=8;i>0;i--)
   	{		
      	SCL=LOW;
      	if(TEST_BIT(value,i-1))
         	SDA=HIGH;
      	else
         	SDA=LOW;	
			SCL=HIGH;            
			Delay();
	}
	SCL=LOW;
	SDA=HIGH;
	SCL=HIGH;
}

uchar Revice_Byte_Memory(void)
{
    uchar  i,value=0;
    for(i=8;i>0;i--)
    {		
        SCL=HIGH;
        Delay();
        if(SDA) 
        	SET_BIT(value,i-1);
        SCL=LOW;
        Delay();
    }
    return value;
}

uchar Write_Device(uchar  addr)
{	
   uchar  i,k;
   for(k=0;k<100;k++)
   {		
      SDA=LOW;
      Delay();
      Send_Byte_Memory(0xa0);
//		SDA=HIGH;	//ADD THIS 2002-04-19		        
      if(SDA==HIGH)continue;
      else goto ack_ok;
   }
   return 1;
ack_ok:                
    i=addr&0xff;
    Send_Byte_Memory(i);
    return 0;
}

uchar Read_From_Memory(uchar *s,uchar  addr,uchar  len)
{
   	uchar i;
		   	
   	if(Write_Device(addr))
      	return 1;
  		 	
   	Set_Start_Condition();
   	Send_Byte_Memory(0xa1);

	SCL=LOW;
	SDA=HIGH;
   	s[0]=Revice_Byte_Memory();
   	for(i=1;i<len;i++)
   	{		                 
    	SDA=LOW;
    	SCL=HIGH;
    	SCL=LOW;
    	SDA=HIGH;
      	s[i]=Revice_Byte_Memory();
   	}
	SCL=HIGH;
	SDA=HIGH;    	
   	Set_Stop_Condition();
   	return 0;
}
	
uchar Write_To_Memory(uchar  *s,uchar  addr,uchar  len)
{ 	
   	uchar temp;
	
start_label:
   	if(Write_Device(addr))
    	return 1;
  	
   	while(len>0)
   	{		
     	len--;
      	Send_Byte_Memory(*s);
      	temp=addr&PAGE_SIZE;
      	addr++;
      	s++;
      	if(temp==PAGE_SIZE)
      	{	
         	Set_Stop_Condition();
         	goto start_label;
      	}
   	}
    Set_Stop_Condition();
    return 0;
}
 
void Delay(void)
{
	;		
}