RTC DS3231 Battery Mode

Projects Programming
1

Hey There!

I'm programming an DS3231 with a standalone µC and i can communicate with the RTC and it send me the contents of his registers.

The breaking point is the writing into the registers. The RTC doesn't accept any data i give but it acknowledges them (to be seen on the oszi).

I have a rootet board where the RTC is put on and only powered by a battery. My question is if i have any programming failure or if the RTC can't be written in Battery mode. In the Datasheet i have only found the nice sentence
"The time and calendar data are set or initialized by writing the appropriate register bytes"

Did anyone have this problem before and could help me?

cheers

2

Hello and welcome,

Read this, it might be helpful :slight_smile:

3

Generally, if you can read the RTC, you can write it. Perhaps you are not coding for it directly, but using a layer of software. If so, we can't help you because we don't know what it is, or what the command set is.

4

Im using a Cortex-M3 µC and a I2C library with it. The RTC acknowledges every frame I'm sending...

5

Then you need to examine the library. Look at the write functions. By the way, this is an Arduino forum.

6

aarg:
By the way, this is an Arduino forum.

Yeah I know but there nobody knows anything about this device...

So but the heck was on me... the implementation of writing was wrong... i only set two times the address and didn't write anything....

Thanks

7

If you have specific questions about the DS3231, feel free to ask. But it sounds like you have it fixed.