Real Time Clock Battery?

What pins are connected to a Real time clock battery. What voltage battery is needed? Do you have any suggestion as to a hardware item for this?


You need a 3V battery on VBAT pin

Just an extension on this question: What code is to be used to update the clock?
Or does it get updated every time you upload new code?

This should be detailed in the ebook

i whas working on the Real TIme Clock of page 103 of the e book yesterday, and i managed to get the clock + date on the lcd & Keypad shield.
First line was the date
second line was the time.

i will be trying to connect 3 volts to the v bat in tonight and keep u updated

Hmmz, i put 3 volts on the vbat in, but when i pull the usb connector out than and wait a minut and plug it back in the clock starts from zero???

anybody ?:stuck_out_tongue:

Can you show us a little schematic on how you wired it?

i just put 3 volts on the vbat in,

  • on vbat
  • on gnd

Check the battery if it fresh. (use multimeter)

When you (plug in or) pull out the usb might cause the connection wires of the battery get loose.

The clock starts from zero might be because there is no power go to the RTC, and it haven’t been set since you get you FEZ.

After you set the time into the RTC, are you issuing a call to:


each time you reboot the system?

The system clock is not automatically loaded from the RTC

The batery shows 02.94 volts is that enough???

i will set the time into the RTC tomorow and keep u informed

2.9V should be just fine.