DS1307 RTC with 8051 ? comes while printing

[td]

hi
i our project,we have connected 89lv51 with RTC DS1307.
here we set the time as
time23:59:36
date31/10/12
and displayed on hyperterminal.at that time, we are getting the time.it is incrementing and displayed on hyper.but some times, it is showing ?.

 

time23:59:36

date31/10/12



time23:59:37

date31/10/12



time????

date??/??/??



time????

date??/??/??



time23:59:40

date31/10/12



time23:59:41

date31/10/12



time????

date??/??/??

......................................

.................................

..............................

time00:01:51

date01/11/12



time00:01:52

date01/11/12





time????

date??/??/??



time00:01:54

date01/11/12



time00:01:55

date01/11/12



time00:01:57

date1?/??/??



time????

date??/??/??



time????

date??/??/??



time????

date??/??/??



time00:02:02

date01/11/12





in this, time and date are incrementing in correct way.but , some times, '?' is coming..

please help me to solve this...

 

[Dexter]

^{it seems the problem is either in programming}

^{or in i2c protocal}

no problem in hardware

 

[td]

THANKS FOR REPLAY…..

 I WILL PASTE MY CODE.BUT I DONT KNOW HOW TO POST. BCOZ THE PROGRAM IS TOO LARGE. I USED    [/CODE]

 

THEN ALSO ONLY SMALL PORTION IS INCLUDING WITHIN THAT TAG….

 

 

I GOT READY MADE PROGRAM./IN THAT I HAVE DONE SMALL CHANGES TO DISPLAY ON HYPERTERMINAL INSTEAD OF LED.THEN ALSO I M NOT GETTIND..

 

PLEASE GUIDE ME..

 

[CODE]   [/CODE]

 

THEN ALSO ONLY SMALL PORTION IS INCLUDING WITHIN THAT TAG….

 

 

I GOT READY MADE PROGRAM./IN THAT I HAVE DONE SMALL CHANGES TO DISPLAY ON HYPERTERMINAL INSTEAD OF LED.THEN ALSO I M NOT GETTIND..

 

PLEASE GUIDE ME..

 

[AJISH ALFRED]

Check the pull up resistors on the I2C lines are soldered properly. Also try changing the RTC chip.

Check for the ‘I2C receive data buffer full’ flag, and try to display only after all the bits are received in the receive buffer.

I hope you got the idea. Any doubts, kindly update.

[Author]

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