So I've noticed that a few DS3231/DS3232 RTC modules you buy off the internet have a I2C EEPROM chip on them. Why? The DS3232 has SRAM already, and a rechargeable battery. The DS3231 doesn't need storage if it has a rechargeable battery on it does it?
So do I need a EEPROM chip if I'm building my own custom RTC with a DS3232?
No. The EEPROM is just a convenience that not many people have asked for; it obviously has more storage capacity than the built-in RAM.
Problem with the built-in RAM is that of the battery ever runs flat, it will loose its content. So it's your call if you need permanent storage next to e.g. the EEPROM storage in an AVR chip (e.g. 328P in an Uno).
But you don't need dedicated EEPROM to store that, as you said, store it in the MCU EEPROM, correct?
If you have an MCU that has EEPROM then use that.
Not all MCUs have EEPROM.
ATMEGA328PB has 1kb, so that should be ok.
Those are not just DS3231, they are combo boards and are flawed. I have the raw chips but prefer the Chronodot modules. I can add EEPROM if I need it.
I am building a dedicated board with a on-board RTC, so modules won't work for me. But I've heard that Chronodot is really good.
In that case all you need is a raw DS3232, I got a handful from Aliexpress.
This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.