lcd.c~

avr MP3 的源程序,包含文件系统,适合初学者

/*------------------------------------------------------------
FileName     : lcd.c
Created by   : ZhengYanbo
Created date : 2006.3.17
Last modified: 2006.3.25
Comments:    : serial drive for st7920
-------------------------------------------------------------*/

#include "lcd.h"
#include "type.h"

flash byte CGRAM[] = {0x10};

//**********************************************************
//初始化与LCD连接的端口
void LCD_port_init(void)
//**********************************************************
{    
    //SID output mode
    SID_PIN_OUT();
    //CLK output mode
    CLK_PIN_OUT();
    //CS output mode
    CS_PIN_OUT(); 
}

//**********************************************************
//用串行方式写一个字节数据到LCD
void serial_write_byte(byte data)
//**********************************************************
{
    byte i;
    
    //SID pin output mode
    SID_PIN_OUT();
    CLK_PIN_OUT();
    CS_PIN_OUT();
    for(i=0; i<8; i++)
    {
    if(data & 0x80) 
     SET_SID();
    else
     CLR_SID();
    //send clk
    CLR_CLK();
    #asm("nop");
    SET_CLK();
    data<<=1;
    }
}

//**********************************************************
//以串行方式从LCD中读一个字节,返回数据
byte serial_read_byte(void)
//**********************************************************
{   
    byte i, temp=0;
    
    //SID pin input mode
    SID_PIN_IN();
    CLK_PIN_OUT();
    CS_PIN_OUT();
    for(i=0; i<8; i++)
    {
    temp<<=1;
    //send clk
    CLR_CLK();
    #asm("nop");
    SET_CLK();
    //wait pin steady
    #asm("nop");
    temp |= (byte)SID_PIN;
    }
    return(temp);    
}

//**********************************************************
//读LCD的状态,读出BF信号
byte LCD_read_status(void)
//**********************************************************
{
    byte temp;
    
    LCD_Enable();
    //send 0b11111100
    serial_write_byte(LCD_READ_STATUS);
    //read upper 4 bits
    temp = serial_read_byte() & 0xF0;
    //read lower 4 bits
    temp = (serial_read_byte() & 0xF0)>>4 + temp;
    LCD_Disable();
    //return its value
    return(temp);
}

//**********************************************************
//忙信号BF检查
//返回: 1->success    0->error(time out)
byte check_busy(void)
//**********************************************************
{
    byte time_out;
    
    time_out=255;
    while(LCD_read_status()&0x80) 
    {
    time_out--;
    //check time out
    if(time_out==0) return 0;
    };
    return 1;
}

//**********************************************************
//写命令到LCM
void LCDWriteCmd(byte command)
//**********************************************************
{   
    //not check BF state
    //delay_us(100);
    //check busy
    check_busy();
    LCD_Enable();
    //send 0b11111000
    serial_write_byte(LCD_WRITE_COMMAND);
    //write upper 4 bits
    serial_write_byte(command & 0xF0);
    //write lower 4 bits
    serial_write_byte((command<<4) & 0xF0);
    LCD_Disable();        
}

//**********************************************************
//写数据到LCM
void LCDWriteData(byte data)
//**********************************************************
{
    //not check BF state
    //delay_us(100);
    //check busy
    check_busy();
    LCD_Enable();
    //send 0b11111010
    serial_write_byte(LCD_WRITE_DATA);
    //write upper 4 bits
    serial_write_byte(data & 0xF0);
    //write lower 4 bits
    serial_write_byte((data<<4) & 0xF0);
    LCD_Disable();
}

//***********************************************************
//Initialize LCD, then print logo
void InitLCD(void)
//***********************************************************
{   
    delay_ms(50);       //Wait LCD ready
    
    LCD_port_init();    //Init LCD port
    
    LCDWriteCmd(0x30);  //function set
    delay_us(100);
    LCDWriteCmd(0x30);  //function set
    delay_us(100);
    LCDWriteCmd(0x0C);  //display on, cursor off
    delay_us(100);
    LCDWriteCmd(0x01);  //clear lcd
    delay_ms(10);
    LCDWriteCmd(0x06);  //Entry mode set 
    
    //Write LCD CGRAM
    LCD_Write_CGRAM(128);      
 
    //Printing Logo
    //LCDclrscr();
    gotoxy(0,0);
    writestring("VS1003 Player");
    gotoxy(1,0);
    writestring("版本: CF v1.0");
    delay_ms(2000);
    //second screen
    LCDclrscr();
    writestring("Key & Com Ctrl");
    gotoxy(1,0);
    writestring("Date:2007.5.18");
    delay_ms(2000);
}

//***********************************************************
void LCD_Write_CGRAM(byte nBytes)
//***********************************************************
{
    //Load user's font characters
    byte i; 
    
    //Set CGram addres;                              
    LCDWriteCmd(0x40);
    //load CGRAM characters  
    for(i=0;i<nBytes;i++) LCDWriteData(CGRAM[i]);  
}

//***********************************************************
void writechar(byte value)
//***********************************************************
{
    //Write 1 character
    //#asm("cli");
    LCDWriteData(value);
    //Set High status
    LCD_Hi_Z();
}

//***********************************************************
//Write a string from flash ROM
void writestring(byte flash *strn)
//***********************************************************
{   
    while (*strn!=0) writechar(*strn++); 
}

//***********************************************************
//Gotoxy function. X=line number, Y=character position
void gotoxy(byte line, byte position)
//***********************************************************
{
    byte address;

    address=lcdLineStart[line]+position;
    LCDWriteCmd(address);
}

//***********************************************************
//Clear LCD
void LCDclrscr(void)
//***********************************************************
{
    LCDWriteCmd(0x01);
    delay_ms(5); //Writing cycle time is 4.6ms for LCD128X64.
}

//***********************************************************
//Setup curson blink, based on player state
void blink(byte on_off)
//***********************************************************
{ 
    //if on_off = 1 blink on, if on_off=0 blink off
    LCDWriteCmd(0x0C + (on_off & 1));
}

//***********************************************************
//Write a decimal number on LCD
void writeNumber(word value)
//***********************************************************
{
    byte temp[8],i=0;
 
    do {
    temp[i++]=value%10;
    value=value/10;
    }
    while (value>0);
    //start from back and print the number 
    for(;i>0;) writechar(temp[--i]+48);
}

//end of lcd.c