16: LCD1602 display

#How to do it

**Schematic**

Code

******************************************************************

* 【Course 17】 ****LCD1602 Experiment***********

* 【illustrate】 ****

* 【Description】 ****Display characters on LCD1602

******************************************************************  

---------------------------------------------------------

Basic operations:

Read status: RS=0,RW=1,EN=1

Output: D0~D7=status word;

Write instruction: RS=0, RW=0, EN=falling edge pulse

D0~D7=instruction code;

Read data: RS=1, RW=1, EN=1

Output: D0~D7=data;

Write data: RS=1, RW=1, EN=falling edge pulse

D0~D7=data;

*********************************************************/

#include //51 header file,

//---------Two commonly used macro definitions-------------- 

#define uint8 unsigned char

#define uint16  unsigned int

//--------1602 control pin definition-------------

sbit RS = P2^5;

sbit RW = P2^6;

sbit EN = P2^7;

//----------Displayed data------------

uint8 Data1[7]="welcom!";

uint8 Data2[13]="www.yxarm.net";

//-----------Function declaration------------------

void DelayMS(uint16 dly);

//----------Declaration of LCD module---------------

bit BUSY(void);

void Write_cmd(uint8 cmd);

void Write_dat(uint8 dat);

void LCD_Init(void);

//---------Main Task---------------------

void main(void)

{

uint8 i;

LCD_Init();

while(1)

{

Write_cmd(0x85); //First line

for(i=0;i<7;i++)

Write_dat(Data1[i]);

Write_cmd(0xc2); //The second line

for(i=0;i<13;i++)

Write_dat(Data2[i]);

}

}

/********************************************************

** Name: void DelayMS(uint16 dly)

** Function: millisecond delay (12M crystal oscillator)

** Entry parameter: dly user's delay parameter   

** Export parameters: None   

*********************************************************/

void DelayMS(uint16 dly)

{

uint16 x,y;

for(x=dly;x>0;x--)

for(y=124;y>0;y--);

}

/********************************************************

** Name: bit BUSY(void)

** Function: Check whether LCD1602 is in busy state;

** Input parameters: None   

** Export parameter: bit Bit

Returns 1, then BUSY

Return 0, then OK   

*********************************************************/

bit BUSY(void)

{

bit Bit;

RS = 0;

RW = 1;

EN = 1;

DelayMS(1);

Bit = (bit)(P0 & 0x80); //The highest bit is the busy signal bit

EN = 0;

return Bit;

}

/********************************************************

** Name: void Write_cmd(uint8 cmd)

** Function: Write command

** Input parameter: cmd control command   

** Export parameters: None   

*********************************************************/

void Write_cmd(uint8 cmd)

{

while(BUSY()); //测忙

RS = 0;

RW = 0;

EN = 0;

P0 = cmd;

EN = 1;

DelayMS(1);

EN = 0;

}

/********************************************************

** Required: void Write_dat(uint8 dat)

** Function: write data

** Input parameter: dat data to be displayed  

** Export parameters: None   

*********************************************************/

void Write_dat(uint8 dat)

{

while(BUSY()); //测忙

RS = 1;

RW = 0;

EN = 0;

P0 = that;

EN = 1;

DelayMS(1);

EN = 0;

}

/********************************************************

** Name: void LCD_Init(void)

** Function: LCD initialization

** Input parameters: None 

** Export parameters: None   

*********************************************************/

void LCD_Init(void)

{

Write_cmd(0x38); //Function setting

DelayMS(1);

Write_cmd(0x0c); //Display switch control

DelayMS(1);

Write_cmd(0x06); //Input mode setting

DelayMS(1);

Write_cmd(0x01); //Clear the LCD display content

DelayMS(1);

}