AD/DA的转换

最新推荐文章于 2025-02-08 21:58:20 发布

原创最新推荐文章于 2025-02-08 21:58:20 发布 · 614 阅读

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本文介绍了一种使用51单片机进行IIC接口编程的方法，包括IIC总线的基本操作如启动、停止、发送和接收数据等，并实现通过IIC接口与AT24C02 EEPROM进行数据读写。此外还展示了如何初始化LCD1602显示器并显示数据，以及如何读取AD转换结果。

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#include <reg52.h>
#include "./delay/delay.h"
#define LCD_WRITE_DATA 1
#define LCD_WRITE_COM 0
#define LCDPORT P0
#define SUCC 0
#define ERR 1
sbit RS = P2^4;
sbit RW = P2^5;
sbit E = P2^6;
sbit SCL = P1^0;
sbit SDA = P1^1;
bit ack = 0;
void iic_start()
{
SDA = 1;
SCL = 1;
delay_us(1);
SDA = 0;
delay_us(1);
SCL = 0;
}
void iic_stop()
{
SDA = 0;
SCL = 1;
delay_us(1);
SDA = 1;
delay_us(1);
SCL = 0;
}
bit iic_send_byte(unsigned char byte)
{
unsigned char i;
SDA = 1;
for(i = 0;i < 8;i++)
{
SDA = byte & 0x80;
SCL = 1;
delay_us(1);
SCL = 0;
byte <<= 1;
}
SCL = 1;
SDA = 1;
delay_us(1);
if(0 == SDA)
{
ack = 1;
}
else
{
ack = 0;
}
SCL = 0;
return ack;
}
void iic_noack()
{
SDA = 1;
SCL = 1;
delay_us(1);
SCL = 0;
}
void iic_ack()
{
SDA = 0;
SCL = 1;
delay_us(1);
SCL = 0;
}
unsigned char iic_rcv_byte()
{
unsigned char i;
unsigned char temp = 0;
unsigned char a;
SDA = 1;
for(i = 0;i < 8;i++)
{
SCL = 0;
delay_us(1);
SCL = 1;
if(SDA == 1)
{
a = 0x01;
}
else
{
a = 0x0;
}
temp |= (a<<(7-i));
delay_us(1);
}
SCL = 0;
return temp;
}
unsigned char AT24C02_send_str(unsigned char devaddr,unsigned char romaddr,unsigned charchar *s,unsigned char num)
{
unsigned char i;
iic_start();
iic_send_byte(devaddr);
if(0 == ack) return ERR;
iic_send_byte(romaddr);
if(0 == ack) return ERR;
for(i = 0;i < num;i++)
{
iic_send_byte(*s);
if(0 == ack) return ERR;
s++;
}
iic_stop();
return SUCC;
}
unsigned char AT24C02_rcv_byte(unsigned char devaddr,unsigned char romaddr,unsigned charchar *s,unsigned char num)
{
unsigned char i;
iic_start();
iic_send_byte(devaddr);
if(0 == ack) return ERR;
iic_send_byte(romaddr);
if(0 == ack) return ERR;
iic_start();
iic_send_byte(devaddr + 1);
for(i = 0;i < num - 1;i++)
{
*s = iic_rcv_byte();
iic_ack();
s++;
}
*s = iic_rcv_byte();
iic_noack();
iic_stop();
return SUCC;
}
void lcd1602_write_data(unsigned char byte,unsigned char flag)
{
if(flag)
{
RS = 1;
}
else
{
RS = 0;
}
RW = 0;
E = 1;
LCDPORT = byte;
delay_us(5);
E = 0;
}
void lcd_init()
{
delay_ms(15);
lcd1602_write_data(0x38,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write_data(0x38,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write_data(0x38,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write_data(0x38,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write_data(0x08,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write_data(0x01,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write_data(0x06,LCD_WRITE_COM);
delay_ms(5);
lcd1602_write_data(0x0c,LCD_WRITE_COM);
delay_ms(5);
}
void lcd_write_str(unsigned char x,unsigned char y,unsigned charchar *p)
{
if((x > 15) || (y > 1))
{
return;
}
if(0 == y)
{
lcd1602_write_data(0x80+x,LCD_WRITE_COM);
}
else
{
lcd1602_write_data(0x80+0x40+x,LCD_WRITE_COM);
}
while(*p != '\0')
{
lcd1602_write_data(*p,LCD_WRITE_DATA);
p++;
}
}
unsigned char AD_read()
{
unsigned char temp;
iic_start();
iic_send_byte(0x90);
if(0 == ack) return ERR;
iic_send_byte(0x40);
iic_start();
iic_send_byte(0x90+1);
if(0 == ack) return ERR;
}
temp = iic_rcv_byte();
iic_noack();
iic_stop();
return temp;
void lcd_dis_char(unsigned char x, unsigned char y, unsigned char byte)
{
if((x > 15) || (y > 1))
{
return ;
}
if(0 == y)
{
lcd1602_write_data(0x80 + x,LCD_WRITE_COM);
}
else
{
lcd1602_write_data(0x80 + 0x40 + x,LCD_WRITE_COM);
}
lcd1602_write_data(byte,LCD_WRITE_DATA);
}
unsigned char DA_write(unsigned char num)
{
iic_start();
iic_send_byte(0x90);
if(0 == ack) return ERR;
iic_send_byte(0x40);
if(0 == ack) return ERR;
iic_send_byte(num);
if(0 == ack) return ERR;
iic_stop();
return SUCC;
}
void main()
{
unsigned char num;
unsigned char test;
unsigned char v;
lcd_init();
while(1)
{
test = AD_read();
v = test*100 / 51;
lcd_dis_char(0,0,(test/100)+0x30);
lcd_dis_char(1,0,(test%100/10)+0x30);
lcd_dis_char(2,0,(test%10)+0x30);
lcd_dis_char(0,1,(v/100)+0x30);
lcd_dis_char(1,1,'.');
lcd_dis_char(2,1,(v%100)/10+0x30);
lcd_dis_char(3,1,(v%10)+0x30);
DA_write(num);
num++;
delay_ms(2);
}
}