ATMEGA8单片机驱动LCD1602液晶C程序_AVR单片机_微控实验网！51单片机AVR单片机教程站 www.mcusy.cn

ATMEGA8单片机驱动LCD1602液晶C程序

发布时间：2009/8/6 阅读次数：4363 字体大小: 【小】【中】【大】

调试过程总结一下：
1）由于找不到de1620资料，不知道它de操作时序。看到一些帖子说1620和1602没区别，还shi有点将信将疑。后面用网友编写de1602程序试验，才知道它们俩没啥区别。
2）关于shi否检测LCD处于空闲，觉得还shi最好在写指令和写数据时都加上。不检测，会导致显示结果不正常。
3）由于连线很多14根（加上背光就shi16根），如果有一根除了问题就会影响到显示。所以我shi用万用表一根线一根线量了之后才通电试验de。
4）看到很多帖子都建议在初始化LCD前延时几十毫秒。本例中并没有延时，显示也正常。
5）总de说来，不shi很难。在遇到问题时只要能够仔细分析，就能找出原因和解决方法。自己前几天在试程序时就shi显示结果不对，一直在检查自己de程序，没想到原来shi单片机deFlash到寿命了……那个郁闷啊…………

头文件中有五个函数:

Function1.unsigned char AskBusy(void) 询问LCD1620shi否空闲, 返回值"1"空闲, "0"为忙;
Function2.WritEDAta(char data) 写数据到LCD1620;
Function3.WriteCommand(char command) 写指令到LCD1620;
Function4.PutOneCharLCD(x,y,*Disp) 在LCD1620上显示一个字符, x,y定义位置
Function5.PutStringLCD(a,b,*DispString) 在LCD1620上显示一个字符串, a,b定义初始位置. Function6.LCD_Init() 初始化LCD

在使用此头文件之前,必须有以下宏定义:

#define DataPortPullup PORTx
#define DataPortDirection DDRx
#define ReadLCDPin PINx
#define CtrlPortPullup PORTx
#define CtrlPortDirection DDRx
#define RS_Bit Px?
#define RW_Bit Px?
#define E_Bit Px?

其中“x”代表B,C,D(mega8中无A口)，"?"代表“0~1”

完整头文件如下（解释搞了一大堆，也学学用英语……）：

/*******************************************************/
/* Project :1620 Display Headfile */
/* Date :2008,3,11 */
/* Author :lhy */
/* Version :v1.1 */
/* Rework :lhy */
/* Rework Date :2008.4.28 */
/* */
/* Comments : */
/* 1 Function Description */
/* Function1.unsigned char AskBusy(void) */
/* --Calls this Fun to ask if LCD is busy, */
/* 1--free,0--busy; */
/* Function2.WritEDAta(char data) */
/* --Write data to LCD */
/* Function3.WriteCommand(char command) */
/* --write command to LCD */
/* Function4.PutOneCharLCD(x,y,*Disp) */
/* --Put one char to LCD. */
/* Function5.PutStringLCD(a,b,*DispString) */
/* --Put String to LCD. Max length 32bits. */
/* */
/* 2 How to use */
/* Before use this HeadFile, */
/* need to define as below: */
/* #define DataPortPullup PORTx */
/* #define DataPortDirection DDRx */
/* #define ReadLCDPin PINx */
/* #define CtrlPortPullup PORTx */
/* #define CtrlPortDirection DDRx */
/* #define RS_Bit Px? */
/* #define RW_Bit Px? */
/* #define E_Bit Px? */
/* x -> A,B,C,D... */
/* ? -> 0,1,2,3,4,5,6,7 */
/* And set control port output,like this: */
/* CtrlPortDirection |= */
/* (1<<E_Bit) | (1<<RS_Bit) | (1<<RW_Bit); */
/* 3 Add the Function "LCD_Init(void)" */
/* Before this Fun, you must set control port */
/* output. */
/*******************************************************/

#ifndef _LCD1620_h
#define _LCD1620_h

//Calls this Fun to ask if LCD is busy,1--free,0--busy
unsigned char AskBusy(void)
{
DataPortDirection = 0x00;
DataPortPullup = 0xff;//enable pullup res
CtrlPortPullup |= (1<<RW_Bit);//Set RW
CtrlPortPullup &= ~(1<<RS_Bit);//Clear RS
CtrlPortPullup |= (1<<E_Bit);//set enable pin
if((ReadLCDPin & (1<<7))==0)
return 1;//lcd is free
else
return 0;//lcd is busy
}

//wait until LCD was free
void WaitForFree(void)
{
unsigned char BusyBit;
do
{
BusyBit = AskBusy();
}
while(BusyBit !=1);
CtrlPortPullup &= (~1<<E_Bit);//Clear enable pin
}

//Write data to LCD
void WritEDAta(char data)
{
WaitForFree();
CtrlPortPullup &= ~(1<<RW_Bit);//Clear RW
CtrlPortPullup |= (1<<RS_Bit);//Set RS

DataPortDirection = 0xff;
DataPortPullup = data;
CtrlPortPullup |= (1<<E_Bit);//set E
CtrlPortPullup &= ~(1<<E_Bit);//Clear E
}

//write command to LCD
void WriteCommand(char command)
{
WaitForFree();
CtrlPortPullup &= ~(1<<RS_Bit);//Clear RS
CtrlPortPullup &= ~(1<<RW_Bit);//Clear RW
DataPortDirection |= 0xff;
DataPortPullup = command;

CtrlPortPullup |= (1<<E_Bit);//set E
CtrlPortPullup &= ~(1<<E_Bit);//Clear E
}

//Write one char to LCD.
void PutOneCharLCD(unsigned char x,unsigned char y,unsigned char *Disp)
{
unsigned char Location;
if(x == 0)
{
Location = y | (1<<7);
}
else if(x == 1)
{
Location = y | (1<<6) |(1<<7);
}
WriteCommand(Location);
WritEDAta(*Disp);
}

//Write String to LCD. Max length 32bits(determined by the location of the first byte).
void PutStringLCD(unsigned char a,unsigned char b,unsigned char *DispString)
{
do
{
PutOneCharLCD(a,b,DispString);
b ++;
DispString ++;
}
while((b <= 15) && (*DispString));

if(*DispString)
{
a ++;//Jump to 2nd row.
b = 0;
do
{
PutOneCharLCD(a,b,DispString);
b ++;
DispString ++;
}
while((b <= 15) && (*DispString));
}
}

//Initialize the LCD1620
void LCD_Init(void)
{
WriteCommand(0x38);//16X2,5X7 lattice,8 bit for transmit
WriteCommand(0x08);//Close the display and cursor
WriteCommand(0x0f);//Set cursor and enable dispaly
WriteCommand(0x06);
WriteCommand(0x01);//Clear the screen
}

#endif

把此头文件包含到主程序中：

/*******************************************************/
/* Project :1620 Display Function */
/* Compiler :ICCAVR 6.03A */
/* Date :2008,4，28 */
/* Author :lhy */
/* Chip type :Atmega8 */
/* Comments : */
/*******************************************************/

＃i nclude "iom8v.h"

#define DataPortPullup PORTD
#define DataPortDirection DDRD
#define ReadLCDPin PIND
#define CtrlPortPullup PORTC
#define CtrlPortDirection DDRC
#define RS_Bit PC0
#define RW_Bit PC1
#define E_Bit PC2

＃i nclude "LCD1620.h"

void main()
{
OSCCAL=0XA5;
CtrlPortDirection |= ((1<<E_Bit)|(1<<RS_Bit)|(1<<RW_Bit));
LCD_Init();
PutStringLCD(0,0,"Li Heng Yuan is a good boy!!");
}

上一篇：基于Atmel的无线传感器网络节点的研究与实现下一篇：ATMEGA8单片机驱动4线步进机C程序

我要评论