RTC chip not keeping time when powered off

[aliyesami]

my DS1307 is not keeping time when powered off , it though saves the current time when powered which is wiered .
It simply continues from the point it left off .
I checked the pin 3 is getting 3.2V from a lithium battery as the datasheet is requiring .
and i am not setting any time in my code also if i had done that i would get same time all the time after power up but as i said it continues from the time I power it off.

thanks

 

[Roll No Three]

May be you have not unset(0) the CH bit in register0 of DS1307

 

[aliyesami]

May be you have not unset(0) the CH bit in register0 of DS1307

I set the time by putting 0x00 into register 00h , doesnt this set the bit 7 in seconds register to 0 ?

 

[Golden Electronics]

Refer my blog it may help u.

 

[aliyesami]

read your blog , i am following all the guidelines there except its not on pcb its on breadboard but I know that can't be my issue as many many people are using RTC circuit on breadboard.
what about the CH bit ? it seems to best fit my problem.

 

[Roll No Three]

Can you plz tell what you are doing in your code.
Also if you have some simulator available like proteus;you can check your code on it too.

 

[aliyesami]

its working now .. the issue was stray capacitence because of breadboard, the issue was fixed by soldering the crystal directly to the chip and putting a 0.01uf capacitor across VBAT - GND.

 

[Roll No Three]

great!!!