main.c

some reference exercise of C language

// Khai bao cac file header
#include	<AT89X52.H>
#include	<Kit8051.h>

// Khai bao cac bien toan cuc
unsigned char code string1[] = "Truong CDSP HN";
unsigned char code string2[] = "8051 Starter Kit";

// Khai bao cac ham
void InitSystem(void);
void Delay(unsigned int n);
void InitLCD(void);
void WriteCommand(unsigned char command);
void WriteCharacter(unsigned char character);
void WriteLCD(unsigned char x);
void SendString2LCD(unsigned char code *p);
void DisplayText(void);

// Dinh nghia cac ham
void InitSystem(void)
{
	// Cam LCD
	LCD_E = 0;
	// Sang den backlight
	LCD_BL = 0;
	// Tre de LCD tu khoi tao ben trong (it nhat 15ms)
	Delay(100);
	// Tat den backlight
	LCD_BL = 1;
	InitLCD();
}
void Delay(unsigned int n)
{
	unsigned int i,j;
	for(i=0;i<n;i++)
		for(j=0;j<100;j++);
}
void InitLCD(void)
{
	WriteCommand(0x30);
	WriteCommand(0x30);
	WriteCommand(0x30);
	
	// 8 bit, 2 lines, font 5x7
	WriteCommand(0x38);
	// Display on, hide cursor
	WriteCommand(0x0C);

	// Xoa man hinh
	WriteCommand(0x01);
}
void DisplayText(void)
{
	// Dich con tro den vi tri thu 2, dong thu nhat
	WriteCommand(0x81);
	SendString2LCD(string1);
	// Dich con tro den dau dong thu hai
	WriteCommand(0xC0);
	SendString2LCD(string2);
}
void WriteLCD(unsigned char x)
{
	LCD_RW = 0;
	LCD_DATA = x;

	LCD_E = 1;
	LCD_E = 0;
	Delay(5);
}
void WriteCommand(unsigned char command)
{
	LCD_RS = 0;
	WriteLCD(command);
}
void WriteCharacter(unsigned char character)
{
	LCD_RS = 1;
	WriteLCD(character);
}
void SendString2LCD(unsigned char code *p)
{
	unsigned char i=0;
	while(p[i]!=0)
	{
		WriteCharacter(p[i]);
		i++;
		Delay(200);
	}
}
// Chuong trinh chinh
void main(void)
{
	// Khoi tao he thong
	InitSystem();
	DisplayText();
	// Vong lap vo tan
	while(1);
}