C51單片機通過I2C對EEPROM進行頁讀取的問題求助

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Calemnt

發布時間: 2018-11-13 07:58

正文摘要:

我在嘗試移植教材上的程序時，發現在頁讀取EEPROM時，第9位應答位假如直接置1或置0，就可以順利讀取，但由形參傳遞1或0給應答位時，就只能讀到一串0，這是什么原因？

回復

ID:111634 發表于 2018-11-14 08:23

實例49 讀寫AT24C02

ID:424091 發表于 2018-11-13 22:11

ahshmj 發表于 2018-11-13 15:53
怎么用圖形貼出來，而不用文本格式呢？別人想試一試程序還要照圖抄一遍？

大佬求幫忙看看

ID:424091 發表于 2018-11-13 17:39

----------------------------------------------------------------主函數
#include <reg52.h>
#define u8 unsigned char
#define u16 unsigned int

extern void Int_Lcd();
extern void Lcd_Show(u8 x,u8 y,u8 *set);
extern void EE_Read(u8 *buf,u8 addr,u8 len);
extern void EE_Write(u8 *buf,u8 addr,u8 len);

void Str_Convert(u8 *str,u8 *src,u8 len);

void main()
{
u8 buf[5]={5,2,8,6,1};
u8 str[20];

Int_Lcd();
// EE_Write(buf,0x00,sizeof(buf));       //EEPROM寫入
EE_Read(buf,0x00,sizeof(buf));       //EEPROM讀取
Str_Convert(str,buf,sizeof(buf));    //字符串轉化函數
Lcd_Show(0,0,str);                   //1cd1602顯示
while(1);
}

void Str_Convert(u8 *str,u8 *src,u8 len)
{
u8 tem;
while(len--)
{
tem=*src>>4;
if(tem<=9)
*str++=tem+'0';
else
*str++=tem-10+'a';
tem=*src&0x0f;
if(tem<=9)
*str++=tem+'0';
else
*str++=tem-10+'a';
*str++=' ';
src++;
}
}
----------------------------------------------------------------LCD1602
#include <reg52.h>
#define u8 unsigned char
#define u16 unsigned int
#define LCD_DB P0

sbit LCD_RS=P2^6;
sbit LCD_RW=P2^5;
sbit LCD_E=P2^7;

void LCD_Wait_Ready()
{
u8 sta;

LCD_DB=0xff;
LCD_RS=0;
LCD_RW=1;
do
{
LCD_E=1;
sta=LCD_DB;
LCD_E=0;
}
while(sta & 0x80);
}

void LCD_Write_Cmd(u8 cmd)
{
LCD_Wait_Ready();
LCD_RS=0;
LCD_RW=0;
LCD_DB=cmd;
LCD_E=1;
LCD_E=0;
}

void LCD_Write_Dat(u8 dat)
{
LCD_Wait_Ready();
LCD_RS=1;
LCD_RW=0;
LCD_DB=dat;
LCD_E=1;
LCD_E=0;
}

void Lcd_Set_Cursor(u8 x,u8 y)
{
u8 addr;
if(y==0)
addr=0x00+x;
else
addr=0x40+x;
LCD_Write_Cmd(addr | 0x80);
}

void Lcd_Show(u8 x,u8 y,u8 *str)
{
Lcd_Set_Cursor(x,y);
while(*str!='\0')
{
LCD_Write_Dat(*str++);
}
}

void Int_Lcd()
{
LCD_Write_Cmd(0x38);
LCD_Write_Cmd(0x0c);
LCD_Write_Cmd(0x06);
LCD_Write_Cmd(0x01);
}
----------------------------------------------------------------I2C
#include <reg52.h>
#include <intrins.h>
#define u8 unsigned char
#define u16 unsigned int

sbit SCL=P2^1;
sbit SDA=P2^0;
sbit LED1=P0^0;
sbit LED2=P0^1;

void Dealy()
{
u8 i;

for(i=0;i<10;i++)
_nop_();
}

void I2C_Start()
{
SDA=1;
SCL=1;
Dealy();
SDA=0;
Dealy();
SCL=0;
Dealy();
}

void I2C_Stop()
{
SCL=0;
SDA=0;
Dealy();
SCL=1;
Dealy();
SDA=1;
Dealy();
}

bit I2C_Write(u8 dat)       //I2C寫入
{
bit ack;
u8 mask;

for(mask=0x80;mask>0;mask>>=1)
{
if((mask & dat)==0)
SDA=0;
else
SDA=1;
Dealy();
SCL=1;
Dealy();
SCL=0;
Dealy();
}
SDA=1;
Dealy();
SCL=1;
ack=SDA;
Dealy();
SCL=0;
Dealy();
return (~ack);
}

u8 I2C_Read(bit ack)       //I2C讀取
{
u8 dat,i;

SDA=1;
Dealy();          //延時10us
for(i=0;i<8;i++)
{
SCL=1;
Dealy();
dat<<=1;
dat |= SDA;
Dealy();
SCL=0;
Dealy();
}
SDA=ack;    //SDA由形參ack控制
Dealy();
SCL=1;
Dealy();
SCL=0;
Dealy();
return dat;
}

u8 I2C_ReadACK()
{
u8 dat,i;

SDA=1;
Dealy();       //延時10us
for(i=0;i<8;i++)
{
SCL=1;
Dealy();
dat<<=1;
dat |= SDA;
Dealy();
SCL=0;
Dealy();
}
SDA=0;    //SDA直接置0
Dealy();
SCL=1;
Dealy();
SCL=0;
Dealy();
return dat;
}

u8 I2C_ReadNAK()
{
u8 dat,i;

SDA=1;
Dealy();
for(i=0;i<8;i++)
{
SCL=1;
Dealy();
dat<<=1;
dat |= SDA;
Dealy();
SCL=0;
Dealy();
}
SDA=1;    //SDA直接置1
Dealy();
SCL=1;
Dealy();
SCL=0;
Dealy();
return dat;
}
----------------------------------------------------------------EEPROM
#include <reg52.h>
#define u8 unsigned char
#define u16 unsigned int

extern void I2C_Start();
extern void I2C_Stop();
extern bit I2C_Write(u8 dat);
extern bit I2C_Read(bit ack);
extern u8 I2C_ReadACK();
extern u8 I2C_ReadNAK();

void EE_Read(u8 *buf,u8 addr,u8 len)    //EEPROM讀取，len讀取長度
{
do
{
I2C_Start();
if(I2C_Write(0x50<<1))
break;
I2C_Stop();
}
while(1);
I2C_Write(addr);          //寫入讀取的起始地址
I2C_Start();
I2C_Write((0x50<<1)|0x01);
while(len>1)
{
*buf++=I2C_Read(0);    //應答位置0
// *buf++=I2C_ReadACK();
len--;
}
*buf=I2C_Read(1);          //應答位置1
// *buf=I2C_ReadNAK();
I2C_Stop();
}

void EE_Write(u8 *buf,u8 addr,u8 len)    //EEPROM寫入
{
while(len>0)
{
do
{
I2C_Start();
if(I2C_Write(0x50<<1))
break;
I2C_Stop();
}
while(1);
I2C_Write(addr);
while(len>0)
{
I2C_Write(*buf++);
len--;
addr++;
if((addr&0x07)==0)
break;
}
I2C_Stop();
}
}

ID:424091 發表于 2018-11-13 17:35