#include "drv_at24cxx.h"
#include "stdio.h"
#include "string.h"


static I2C_t *prv_i2c = NULL;//私有i2c指针

I2C_t* AT24C_Init(I2C_HandleTypeDef *hi2c)
{
	I2C_t* i2c;
	i2c = (I2C_t *)malloc(sizeof(I2C_t));
	
	i2c->hi2c = hi2c;
	i2c->address = DEV_ADDR;
	i2c->page_num = PAGE_NUM;
	i2c->page_size = PAGE_SIZE;
	i2c->capacity = CAPACITY_SIZE;
	i2c->addr_num = ADDR_BYTE_NUM;
	
		i2c->delay = 2;
	
	
	/**
	* 给全局变量赋值
	*/
	prv_i2c = i2c;
	
	return i2c;
}




unsigned char AT24C_Write(uint16_t addr,uint8_t* buff,uint16_t len)
{
	if(!prv_i2c)
	{
		return HAL_ERROR;
	}
	
	HAL_StatusTypeDef rst;
	
	uint16_t i = 0;
    uint16_t cnt = 0;        //写入字节计数
	uint16_t head;
	uint16_t left;
	uint16_t tail;
	
	if((len + addr - 1)/prv_i2c->page_size == addr/prv_i2c->page_size)		//如果在同一页
	{
		rst = HAL_I2C_Mem_Write(prv_i2c->hi2c, prv_i2c->address | 0x00, addr, prv_i2c->addr_num, buff, len, 0xFFFF);
		HAL_Delay(prv_i2c->delay * len);
	}
	else
	{
		head = (addr / prv_i2c->page_size+1) * prv_i2c->page_size - addr;	//开始页剩余待写入字节数
		left = len - head;													//除去开始页剩下字节数
		tail=left-left/prv_i2c->page_size*prv_i2c->page_size;				//末页待写入字节数
		
		rst = HAL_I2C_Mem_Write(prv_i2c->hi2c, prv_i2c->address | 0x00, addr, prv_i2c->addr_num, buff, head, 0xffff);
		HAL_Delay(prv_i2c->delay * head);
		
		for(i=0; i<left/prv_i2c->page_size; i++)
		{
			rst = HAL_I2C_Mem_Write(prv_i2c->hi2c, prv_i2c->address | 0x00, addr + head + i * prv_i2c->page_size, prv_i2c->addr_num, buff + head + i * prv_i2c->page_size , prv_i2c->page_size, 0xFFFF);
			HAL_Delay(prv_i2c->delay*prv_i2c->page_size);
			
			if(rst != HAL_OK)
			{
				return (unsigned char)rst;
			}
		}
		
		rst = HAL_I2C_Mem_Write(&hi2c1, prv_i2c->address | 0x00, addr + head + i * prv_i2c->page_size, prv_i2c->addr_num, buff + head+ i * prv_i2c->page_size, tail, 0xffff);
		HAL_Delay(prv_i2c->delay * tail);
	}
	
	return (unsigned char)rst;
}

unsigned char AT24C_Read(uint16_t addr,uint8_t* buff,uint16_t len)
{
	if(!prv_i2c)
	{
		return HAL_ERROR;
	}
	
	HAL_StatusTypeDef rst;
	
	if(addr + len < 0x8000)
	{
		rst = HAL_I2C_Mem_Read(prv_i2c->hi2c, prv_i2c->address | 0x01, addr, prv_i2c->addr_num, buff, len, 0xffff);
	}
	
	return (unsigned char)rst;
}

uint8_t AT24C_Check(void)
{
        uint8_t temp;
        uint8_t data = 0XAB;

        AT24C_Read(0x00,&temp,1);//避免每次开机都写AT24CXX                           

        if(temp != 0XAB)
		{
                return 1;                   
		}
        else//排除第一次初始化的情况
        {
            AT24C_Write(0x00,&data,1);
            AT24C_Read(0x00,&temp,1);
			
			if(temp != 0XAB)
			{
					return 1;
			}
        }
        return 0;                                                                                          
}



void AT24C_Fill(uint8_t fill)
{
	uint8_t erase[512];//这个缓存太大
	memset(erase,fill,512);
	for(uint16_t i=0;i<64;i++)
	{
		AT24C_Write(i*512,erase,512);
	}
}