Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Time issue with DS1307 Interfaced With PIC18F452

Status
Not open for further replies.
B

bilal shareef

Member level 1
Joined
Dec 11, 2010
Messages
36
Helped
1
Reputation
2
Reaction score
1
Trophy points
1,288
Activity points
1,549
I am using DS1307 in my project for timing ... DS1307 has got a backup battery which runs the time when we has switched of the controller. . . but the problem is that when i turn off the power of DS1307
it stops and does not measure the time....And when i switch on the controller again .. it resumes form the time where i switched it off....

According to the datasheet and the function of the DS1307 it should run all the time wether we have given it the supply or not .. by using it backup battery ... i need help to solve this problem.....
 

Can you post the circuit?
Also, I hate to ask, but is this a real circuit or simulated circuit?
 

RTC-sim.gif

this is the circuit diagram ... And this is the real circuit ... on simulation it works fine but on hardware it has the above mentioned problem....
 

This is your simulated circuit, not your real circuit. The real circuit would have a battery (what voltage/size?) and I'd like to see how it is connected, e.g. is the -ve terminal of the battery connected to 0V? Also, what kind of crystal did you use, was it the small cylindrical ones, or HC49/U style? What supply does the DS1307 run from when it is powered from the main supply? None of this information is available from the circuit diagram. Also, can you post a photo of the DS1307 portion of your hardware?
 

okay! please see the image that i have attached. It has the details. I could not attach a real hardware photo cause i have no connecting cable. Earlier i told you that when i turned off main supply suppose the time was 12:35 at that moment, then swtiching On the supply after some, the time was found to be 12:35 and continued so on. That measns it was being retained by the cell in the memory of DS1307. So, i did a little experiment. I took out the cell from it's socket and then turned on my hardware and fed a new time. I set a time on it. and then I turned off the main supply. After some time, when i switched ON the circuit, the time was found to be 00. It means that the old time was lost and was not being retained if the cell was gone.DS.png
 

Sounds like a duff battery, maybe on the verge of storing the clock state, but not enough power to drive the xtal.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top