I am using the RTClib library to talk to a DS1307 RTC circuit connected to an Arduino. The library makes it a breeze to time stamp data and perform tasks at fixed times. Hats off to the author of RTClib.
The only thing that I can't resolve is this: The RTC time is set to the PC time when the sketch is compiled. By the time the program is uploaded there can be a 20-40 second difference between PC time and RTC time. This can start to make some datasets look a little screwy.
I understand the RTC can be set on the fly with an ethernet shield, but I don't have one. Can anyone think of a way the RTC be reset/adjusted while the Arduino code is running to get it exactly right (well, to within 1 second)?
Any advice much appreciated.
Accurately setting Ds1307 with RTClib after compiling sketch
Moderators: adafruit_support_bill, adafruit
Please be positive and constructive with your questions and comments.
-
- Posts: 6
- Joined: Wed Dec 14, 2011 3:27 pm
- Franklin97355
- Posts: 23912
- Joined: Mon Apr 21, 2008 2:33 pm
Re: Accurately setting Ds1307 with RTClib after compiling sketch
You could put a check in the start of the program to see if a pin was pulled low and if so ask for the date and time.
- fat16lib
- Posts: 595
- Joined: Wed Dec 24, 2008 1:54 pm
Re: Accurately setting Ds1307 with RTClib after compiling sketch
The softDS1307 example in my I2cMaster library allows you to accurately set the DS1307. It will work with the Data Logging shield on a Mega or 328 Arduino.
You can download it from this post http://forums.adafruit.com/viewtopic.php?f=25&t=13722. The file is i2cv2.zip.
Here is the menu and entries for setting the time:
You can download it from this post http://forums.adafruit.com/viewtopic.php?f=25&t=13722. The file is i2cv2.zip.
Here is the menu and entries for setting the time:
The current time is 12/18/2011 Sun 13:49:06
Control: 00
Options are:
(0) Display date and time
(1) Set time
(2) Set date
(3) Set Control
(4) Dump all
(5) Set NV RAM
Enter option: 1
Enter hours (00-23): 13
Enter minutes (00-59): 50
Enter seconds (00-59): 00
The current time is 12/18/2011 Sun 13:50:00
Control: 00
- boomerang
- Posts: 7
- Joined: Wed Feb 08, 2012 8:02 am
Re: Accurately setting Ds1307 with RTClib after compiling sketch
Would this involve sending the time over serial? I would love to be able to do this. I could be poised to hit 'enter' while watching the clock for the time I've set to come by.franklin97355 wrote:You could put a check in the start of the program to see if a pin was pulled low and if so ask for the date and time.
Is there a library for this?
Please be positive and constructive with your questions and comments.