单片机的学习（15）--LCD1602

14.1LCD1602的基础知识

1.LCD1602介绍

LCD1602(Liquid Crystal Display)液晶显示屏是一种字符型液晶显示模块，可以显示ASCII码的标准字符和其它的一些内置特殊字符，还可以有8个自定义字符
显示容量：16×2个字符，每个字符为5*7点阵

2.引脚及应用电路

3.内部结构框图

4.时序结构

5.LCD1602指令集

6.字符值

7.LCD1602操作流程

14.2LCD1602功能函数代码

1.显示一个字符

（1）工程目录

（2）main.c函数

#include <REGX52.H>
#include "LCD1602.h"
void main()
{
	LCD_Init();
	LCD_ShowChar(2,3,'A');
	while(1)
	{
		
	}
}

（3）LCD1602.c函数

#include <REGX52.H>

sbit LCD_RS=P2^6;
sbit LCD_RW=P2^5;
sbit LCD_E=P2^7;
#define LCD_DataPort P0

void LCD_Delay()		//@11.0592MHz  1ms
{
	unsigned char data i, j;

	
	i = 2;
	j = 199;
	do
	{
		while (--j);
	} while (--i);
}

void LCD_WriteCommand(unsigned char Command)
{
	LCD_RS=0;
	LCD_RW=0;
	LCD_DataPort=Command;
	LCD_E=1;
	LCD_Delay();
	LCD_E=0;
	LCD_Delay();
}

void LCD_WriteData(unsigned char Data)
{
	LCD_RS=1;
	LCD_RW=0;
	LCD_DataPort=Data;
	LCD_E=1;
	LCD_Delay();
	LCD_E=0;
	LCD_Delay();
}
void LCD_Init(void)
{
	LCD_WriteCommand(0x38);
	LCD_WriteCommand(0x0C);
	LCD_WriteCommand(0x06);
	LCD_WriteCommand(0x01);
}

void LCD_ShowChar(unsigned char Line,unsigned char Column,unsigned char Char)
{
	if(Line==1)
	{
		LCD_WriteCommand(0x80|(Column-1));
	}
	else
	{
		LCD_WriteCommand(0x80|(Column-1)+0x40);
	}
	LCD_WriteData(Char);
}

补充知识点：字符和字符串
字符：根据一定规则建立的数字到字符的映射(ASCII码表)
例如：0x21=‘!’.0x41=‘A’.0x00=\0’
定义方法：char x=‘A’：(等效干char x=0x41:)

字符数组：存储字符变量的一个数组
定义方法：char y[]=f’A’，‘B’，‘C’;(等效于char y[]={0x41，0×42，0×43；)

字符串：在字符数组后加一个字符串结束标志，本质上是字符数组定义方法：char z[]="ABC”；(等效于char z[]=f’A’，‘B’，’C’，\O；)

2.显示一组字符串

（1）代码

void LCD_ShowString(unsigned char Line,unsigned char Column,unsigned char String[])
{
	unsigned char i;
	LCD_SetCursor(Line,Column);
	for(i=0;String[i]!='\0';i++)
	{
		LCD_WriteData(String[i]);
	}
}

2.显示数字

（1）无符号代码

void LCD_ShowNum(unsigned char Line,unsigned char Column,unsigned int Number,unsigned char Length)
{
	unsigned char i;
	LCD_SetCursor(Line,Column);
	for(i=Length;i>0;i--)
	{
		LCD_WriteData('0'+Number/LCD_Pow(10,i-1)%10);
		
	}
}

（2）有符号代码

void LCD_ShowSignedNum(unsigned char Line,unsigned char Column,int Number,unsigned char Length)
{
	unsigned char i;
	unsigned int Number1;
	LCD_SetCursor(Line,Column);
	if(Number>=0)
	{
		LCD_WriteData('+');
		Number1=Number;
	}
	else
	{
		LCD_WriteData('-');
		Number1=-Number;
	}
	for(i=Length;i>0;i--)
	{
		LCD_WriteData('0'+Number1/LCD_Pow(10,i-1)%10);
		
	}
}

2.显示进制

（1）十六进制

void LCD_ShowHexNum(unsigned char Line,unsigned char Column,unsigned int Number,unsigned char Length)
{
	unsigned char i;
	unsigned char SingleNumber;
	LCD_SetCursor(Line,Column);
	for(i=Length;i>0;i--)
	{
		SingleNumber=Number/LCD_Pow(16,i-1)%16;
		if(SingleNumber<10)
		{
			LCD_WriteData('0'+SingleNumber);
		}
		else
		{
			LCD_WriteData('A'+SingleNumber-10);
		}
	}
}

（1）二进制

void LCD_ShowBinNum(unsigned char Line,unsigned char Column,unsigned int Number,unsigned char Length)
{
	unsigned char i;
	LCD_SetCursor(Line,Column);
	for(i=Length;i>0;i--)
	{
		LCD_WriteData('0'+Number/LCD_Pow(2,i-1)%2);
		
	}
}