Tiny RTC Module

[Simon X. (simon1720)]

Hallo zusammen ich habe ein Problem. Ich versuche ein Tiny RTC Module in 
Betrieb zu nehmen mit einem Atmega644PA. Dafür habe ich folgendes 
Programm. Allerdings komme ich nicht mehr weiter. Wen ich mit eine 
Analyser die I2C Leitung ausmesse, sehe ich das das Signal nur einmal 
gesendet wird aber nur bis zur hälfte. Ich hoffe mir kann hier jemand 
helfen dieses Problem zu lösen. Im Anhang ist der C Code.

#include <avr/io.h>

#define uint unsigned int 
#define uchar unsigned char

void twi_init(void);
void writebyte(uchar temp);
uchar TWI_Write(uchar addr,uchar dat);
uchar TWI_Read(uchar addr);
uchar Decimal_to_BCD(uchar temp);
uchar BCD_to_Decimal(uchar temp);  
void delay_2(uint z);
void delay_1(void);
void write_ds1307(void);
void read_ds1307(void);


//sda=PD1;//;TWI Data transmission bit
//scl=PD0;//;TWI Clock control state flag
//RS=PC0;//define the I / O hardware interface of LCD1602
//RW=PC1;//define the I / O hardware interface 0f LCD1602 
//E=PC2; //define the I / O hardware interface 0f LCD1602 
uchar count;
uchar Hours=16;//Definition of hours
uchar Minutes=21;//Definition of minutes
uchar Seconds=0;//Definition of seconds

uint  Year=12;//Definition of year
uchar Month=7;//Definition of month
uchar Date=27;//Definition of date
uchar Weeks=5;//Definition of weeks 


#define START     0X08   //start() has been successfully sent
#define RESTART   0X10 //The restart() has been successfully sent
#define MT_SLA_ACK   0X18 //Load data has been sent ack()
#define MT_SLA_NACK 0X20 //Load data has been sent nack()
#define MT_DAT_ACK   0X28  //Data has been sent ack()
#define MT_DAT_NACK 0X30 //Data has been sent nack()
#define SL_SLA_ACK   0X40 //Data has been loaded from the machine to send ack()
#define SL_SLA_NACK 0X48 //Data has been loaded from the machine to send nack()
#define SL_DAT_ACK   0X50  //Slave data has been sent ack()
#define SL_DAT_NACK 0X58  //Slave data has been sent nack()

#define start()   TWCR=((1<<TWINT)|(1<<TWSTA)|(1<<TWEN)) //Send start signal
#define restart()   TWCR=((1<<TWINT)|(1<<TWEN)|(1<<TWSTA)) //Sent to re-start signal
#define wait()    while(!(TWCR & (1<<TWINT))) //Waiting for the signal
#define state()   (TWSR&0XF8) //The register TWSR state extraction
#define stop()     TWCR=((1<<TWEN)|(1<<TWINT)|(1<<TWSTO)) //Stop signal
#define twi()    (TWCR=(1<<TWINT)|(1<<TWEN))  //Open the TWI function
#define setnoAck()  (TWCR&=~(1<<TWEA))        //Make Not Ack response

#define r_direction 0xD1 //Read the device address
#define w_direction 0xD0 //Write device address

void twi_init(void)  //TWI initialization
{
   TWCR |=(1<<TWEN); //Start twi function
   TWBR=0X20;  //Set the baud rate for the host mode
   TWSR=0;    //Clear Status Register
}

void writebyte(uchar temp)//A byte data write to the TWI
{
  TWDR=temp;
  TWCR=((1<<TWINT)|(1<<TWEN));
}
uchar TWI_Write(uchar addr,uchar dat) //Write data to TWI
{
   start();//start signal
   wait();//Start TWI function
   if(state()!=START)//Wait for the nack/ack() signal
   return 1;

   writebyte(w_direction);//write    Device address
   wait();
   if(state()!=MT_SLA_ACK)
   return 1;

   writebyte(addr);//write      Byte address
   wait();
   if(state()!=MT_DAT_ACK)
   return 1;

   writebyte(dat);//write     data
   wait();
   if(state()!=MT_DAT_ACK)
   return 1;

   stop();//stop signal
   return 0;
}

uchar TWI_Read(uchar addr) //Read data from TWI
{
     uchar temp=0;
     start();//
  wait();
  if(state()!=START) 
  return 1;           //ACK*/     

  writebyte(w_direction);  //Write TWI slave address and write
  wait(); 
  if(state()!=MT_SLA_ACK) 
  return 1;            //ACK*/

  writebyte(addr);    //Write the corresponding device register address
  wait();
  if(state()!=MT_DAT_ACK) 
  return 1;//*/

  start();                  //TWI re-start
  wait();
  if (state()!=RESTART)  
  return 1;//*/

  writebyte(r_direction);  //Write TWI slave device address and read
  wait();
  if(state()!=SL_SLA_ACK)  
  return 1;           //ACK*/

  twi();              //Start the TWI read
  wait();
  if(state()!=SL_DAT_NACK) 
  return 1;          //ACK*/  

  temp=TWDR;//Read the TWI of the receive data
  stop();//
  return temp;


}
/////////////////////////////////////////
//////////////////////////////////////////
uchar Decimal_to_BCD(uchar temp)//Decimal converted to BCD code
{
  uchar a,b,c;
  a=temp;
  b=0x00;
  if(a>=10)
  {
    while(a>=10)
    {
      a=a-10;
      b=b+16;
      c=a+b;
      temp=c;
    }
  }
  return temp;
}

uchar BCD_to_Decimal(uchar temp)//BCD to decimal
{
  uchar a,b,c;
  a=temp;
  b=0x00;
  if(a>=16)
  {
    while(a>=16)
    {
      a=a-16;
      b=b+10;
      c=a+b;
      temp=c;
    }
  }
  return temp;
}
////////////////////////////////////////  
void delay_2(uint z)//0.1msDelay
{ 
  uchar x,x1;
  for(x1=0;x1<z;x1++)
  {
    for(x=0;x<114;x++);
  }
}

void delay_1(void)//0.1msDelay
{ 
  uchar x,x1;
  for(x1=0;x1<2;x1++)
  {
    for(x=0;x<100;x++);
  }
}

void write_ds1307(void)//write ds1307
{
  //Write a data to the device: (0xd0 is device write address; 0x01 ~ 06 are seconds to years register; Seconds ~ Year, data to be written)//
  Seconds=Decimal_to_BCD(Seconds);//Decimal converted to BCD code
  Minutes=Decimal_to_BCD(Minutes);//
  Hours=Decimal_to_BCD(Hours);//
  
  Date=Decimal_to_BCD(Date);//
  Year=Decimal_to_BCD(Year);//
  Month=Decimal_to_BCD(Month);//
  
  TWI_Write(0x00,Seconds);//write Seconds
  TWI_Write(0x01,Minutes);//write Minutes
  TWI_Write(0x02,Hours);//write Hours
  
  TWI_Write(0x03,Weeks);//write Weeks

  TWI_Write(0x04,Date);//write Data
  TWI_Write(0x05,Month);//write Month
  TWI_Write(0x06,Year);//write Year
}

void read_ds1307(void)//read ds1307
{
  //Read a data to the device: (0xd0 is the DS1307 device write address; 0x01 ~ 06 are seconds to years register; 0xd1 is DS1307 device read address) 
  Seconds=TWI_Read(0x00);
  Seconds=BCD_to_Decimal(Seconds);//BCD code converted to decimal
  
  Minutes=TWI_Read(0x01);
  Minutes=BCD_to_Decimal(Minutes);//

  Hours=TWI_Read(0x02);
  Hours=BCD_to_Decimal(Hours);//
  
  Weeks=TWI_Read(0x03);//

  Date=TWI_Read(0x04);
  Date=BCD_to_Decimal(Date);//
  
  Month=TWI_Read(0x05);
  Month=BCD_to_Decimal(Month);//

  Year=TWI_Read(0x06);
  Year=BCD_to_Decimal(Year);//
}  

int main(void)
{
  DDRA = 0x77;
  DDRB = 0x77;
  
  DDRC = 0x00;
  PORTC = 0x03;
  
  twi_init();//TWI Initialization
  
  //write_ds1307();//Write the initial value on ds1307//(Modification time initial value when used)
  while(1)
  {
    read_ds1307();
    
    if(Seconds & 1)
    {
      PORTA = 0x07;
    }
     else
     {
       PORTA = 0x00;
     }
    
    for(uint16_t i = 0x0FFF; i; i--);
  }
}