如何将输出数据从DS1307打印到LCD 16x2

Question

我有个简单的项目。我有一个ATmega32连接到一个16x2LCD和一个DS13027芯片。我使用8位数据与16x2液晶显示器。下面是密码。

#define F_CPU 8000000UL

#define LCD_DPRT  PORTA     
#define LCD_DDDR  DDRA      
#define LCD_DPIN  PINA      
#define LCD_CPRT  PORTB     
#define LCD_CDDR  DDRB      
#define LCD_CPIN  PINB      
#define LCD_RS  0           
#define LCD_RW  1           
#define LCD_EN  2

#include <avr/io.h>
#include <util/delay.h>

void i2c_stop(void);
void i2c_write(unsigned char data);
void i2c_start(void);
void i2c_init(void);
unsigned char i2c_read(unsigned char ackVal);
void rtc_init(void);
void rtc_setTime(unsigned char deviceRegister, unsigned char value);
unsigned char *rtc_getTime(unsigned char deviceRegister);
void lcdCommand( unsigned char cmnd );
void lcdData( unsigned char data );
void lcd_init();
void lcd_gotoxy(unsigned char x, unsigned char y);
void lcd_print( const char * str );

int main(void) {

    unsigned char *hours;

    rtc_init();
    rtc_setTime(0x02, 0x22);

    hours = rtc_getTime(0x02);

    lcd_init();
    lcd_gotoxy(1,1);
    lcd_print(hours[0]);
    lcd_gotoxy(2,1);
    lcd_print(hours[1]);

    while (1);
    return 0;
}

void i2c_stop(void){
    TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
}

void i2c_write(unsigned char data){
    TWDR = data;
    TWCR = (1<<TWINT) | (1<<TWEN);
    while(!(TWCR & (1<<TWINT)));
}

void i2c_start(void){
    TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
    while(!(TWCR & (1<<TWINT)));
}

void i2c_init(void){
    TWSR = 0x00;
    TWBR = 0x47;
    TWCR = 0x04;
}

unsigned char i2c_read(unsigned char ackVal){
    TWCR = (1<<TWINT) | (1<<TWEN) | (ackVal<<TWEA);
    while( !( TWCR & (1<<TWINT)) );
    return TWDR;
}

void rtc_init(void){
    i2c_init();
    i2c_start();
    i2c_write(0xD0);
    i2c_write(0x07);
    i2c_write(0x00);
    i2c_stop();
}

void rtc_setTime(unsigned char deviceRegister, unsigned char value){
    i2c_start();
    i2c_write(0xD0);
    i2c_write(deviceRegister);
    i2c_write(value);
    i2c_stop();
}

unsigned char *rtc_getTime(unsigned char deviceRegister){

    unsigned char *data;

    i2c_start();
    i2c_write(0xD0);
    i2c_write(deviceRegister);
    i2c_stop();

    i2c_start();
    i2c_write(0xD1);
    *data = i2c_read(0);
    i2c_stop();

    return data;
}

void lcdCommand( unsigned char cmnd ){
  LCD_DPRT = cmnd;          
  LCD_CPRT &= ~ (1<<LCD_RS);
  LCD_CPRT &= ~ (1<<LCD_RW);
  LCD_CPRT |= (1<<LCD_EN);  
  _delay_us(1);             
  LCD_CPRT &= ~ (1<<LCD_EN);
  _delay_us(100);           
}

void lcdData( unsigned char data ){
  LCD_DPRT = data;          
  LCD_CPRT |= (1<<LCD_RS);  
  LCD_CPRT &= ~ (1<<LCD_RW);
  LCD_CPRT |= (1<<LCD_EN);  
  _delay_us(1);             
  LCD_CPRT &= ~ (1<<LCD_EN);
  _delay_us(100);           
}

void lcd_init(){
  LCD_DDDR = 0xFF;
  LCD_CDDR = 0xFF;

  LCD_CPRT &=~(1<<LCD_EN);  
  _delay_us(2000);          
  lcdCommand(0x38);         
  lcdCommand(0x0E);         
  lcdCommand(0x01);         
  _delay_us(2000);          
  lcdCommand(0x06);         
}

void lcd_gotoxy(unsigned char x, unsigned char y){  
 unsigned char firstCharAdr[]={0x80,0xC0,0x94,0xD4};//table 12-5  
 lcdCommand(firstCharAdr[y-1] + x - 1);
 _delay_us(100);    
}

void lcd_print( const char * str ){
  unsigned char i = 0 ;
  while(str[i]!=0)
  {
    lcdData(str[i]);
    i++ ;
  }
}

当我运行这个程序时，LCD上什么都不会出现。我不知道为什么它不输出时间在液晶显示器上。

1. 为什么不显示在LCD上？
2. 如何输出LCD上的小时(代码明智)？

Answer 1

可能是显示项。如果您有一个与标准控制器HD44780兼容的显示器，您可以尝试以下方法(多年前我在PIC程序集中为1x16编写了它，所以我不会直接在这里发布此代码)：

Enable

• lcdCommand(0x38)

• 在LCD数据总线上放置0x30，保持RW和RS行低(命令模式)等待25 RS

• Strobe启用，即Ena=high、等待1或2 s、Ena=low

• 等待4.1ms

H19Strobe Enable H 210H 111等待140

• H 212/code>H 113µ//；功能集:以8位模式显示，5x7 Font

• lcdCommand(0x0C) //0x0E可能与yout lcd

• lcdCommand(1) //clear

• lcdCommand(0x06) //；入口模式集一样正确:自动增长，没有Shift

• lcd_gotoxy(1,1)