Reason for corruption of data from DS3232.

jaikumar · Joined: 15 Dec 2006 Posts: 109

Hi All,

I am using a DS3232 with 18F2550 I2C. When i set the date and time it works. but when i switch on and off a few times either the date or time
gets corrupted. The value some times is even greater than 12 for month.

Data does not get corrupted as long as power is not switched on/off

Need help on what might be the causes.

Thanks and Regards,
Jai.

bkamen · Posted: Thu Mar 17, 2011 12:17 am

You do have a battery attached, yes?

-Ben
_________________
Dazed and confused? I don't think so. Just "plain lost" will do. :D

jaikumar · Joined: 15 Dec 2006 Posts: 109

Yes. Battery voltage is also fine.

jaikumar · Joined: 15 Dec 2006 Posts: 109

When using CCS ICD-U64 the MCLR pin is kept at 4.5 V. I removed the ICD connections during power cycle. The data has not got corrupted. Will test further to determine if this is THE cause.

regards
jai

jaikumar · Joined: 15 Dec 2006 Posts: 109

That was not the cause.
Any other ideas?

regards,
jai

temtronic · Posted: Thu Mar 17, 2011 5:45 am

Other things to look at.

Properly designed power supply,especially EMI filtering...

Enable PUT in Fuses...

Correct ground layout and local bypass caps, one per chip.

Correct pullups, based on Vdd and speed..

Ttelmah · Joined: 11 Mar 2010 Posts: 19504

Take us through the supply circuitry, and the layout of the I2C connections (pullup values, do you have inline resistors as well?).

Best Wishes

PCM programmer · Joined: 06 Sep 2003 Posts: 21708