Date and Time lost with Teensy 4.1

[Videophile]

This is my first post here!

I don't know if newcomers need to presents themselves here, but just in case: I have already done several projects with Arduino and a few with Teensy boards, so I would qualify me as an "advanced hobbyist". Usually, when I have a problem, I find the solution in the technical documentation or in forums. But in this case, I am running out of ideas...

So here is my problem: I use a Teensy 4.1, I have connected a coin battery to VBAT, the voltage is correct (2,99V), but still, the date and time revert to 01/01/1970 00:00 each time I switch off the Teensy. The Teensy is powered through USB for now. I use the setTime function to set the date and time, and I get the current date and time using the year(), month(), etc. functions. I use the Arduino 2.0 IDE.

What am I doing wrong ?

 

[PaulS]

Welcome to the forum!
You may have missed the Forum Rule at the top of this page: "Always post complete source code & details to reproduce any issue!"

It helps a lot when you post your code so that other forum members can just copy and paste the code into their Arduino IDE and try to reproduce [and help solve] the problem. Photo's of your setup will also help.

Please use code tags by clicking the # sign when posting code:



Paul

 

[PaulStoffregen]

What am I doing wrong ?

Blind guessing... (since you didn't show us what you've attempted)

Maybe you're using the Time library?

Maybe you didn't use setSyncProvider() to cause the Time library to sync to Teensy's RTC clock? To see how, open the example by clicking File > Examples > Time > TimeTeensy3.

 

[Videophile]

@PaulS: sorry for not respecting the forum rules, I will post my code next time. As usual, I didn't read the manual, but this is no excuse . However, for this issue, it won't be needed, because...

...@PaulStoffregen: spot on, thanks a lot for your help!