I2C RTC DS1307

yea i know I2C. the above program is working very fine and also i am able to set the time also.DS1307 requires
1. start
2.writing the address read (DO)or Write(D1)
3.Read ACK
4.Send ACk
5.Send not ACK
6. STOP
but configuring the port is not same like 8051
because in 8051 Seperately we can do program
but here the data direction may change whole ports

I am not able to understand your program actually...
As you said you are able to set time.. how you know that time is getting set? and moreover if I2C is working... what is the problem then.. i am kind of confused :-s

i am using modbus protocol and also i will set the time from system . the same way i get the time from RTC through USART of ATMEGA8515. ...

you need to translate the data sent via serial terminal...
like if you are reading as..
"12:44 am"
then you need to code the way that you break up this data and store the values in respective variables and then store it in the RTC as you are doing already...

ok.thanks.but we are connecting our device to PLC DCS, due to that we are using modbus protocol