MTRTC001 - Chronodot Precision Clock Module

I'm using this rtc is the heart of my first arduino gadget, a high end digital clock. The hookup is super simple and the unit keeps great time and has advanced features like battery backup and 2 alarm settings that are useful. One heads up, for basic "read the time" type operations various libraries and code written for the DS1307 rtc work fine. However, if you need to implement an alarm clock...you'd be better off starting with a library for the DS3231 rtc, which is what the chronodot is. I was pretty far into my coding before figuring this out and since many of the functions were implemented differently in the correct library, I had a lot of editing to do that I could have avoided.Anyway...the chronodot works great and I'll be using it on my future clock projects as well.

I built a clock with a cheap RTC, but it drifts like a sailor who doesn't account for current OR magnetic north. I swapped out that RTC for this one, and without even changing my sketch at all, the Chronodot just worked perfectly with it. Where my old RTC would drift about 20 minutes per month, this one's been spot on for weeks now. Winner.

Pretty neat little device. But if you get one, use Truchsess's I2CLibrary rather than the standard Wire library on the Arduino. Wire doesn't handle repeat-START well and loses its synch over time. Good software library support for this.

Works great with my Arduino project, and I am a beginner. Easy to connect, great software interfaces readily available. And, you get the bonus of having an ambient temperature value available too if that is useful for your project.

Plug and play real time clock for the Pi. Just wire it up as described here: http://rpi.fatdog.eu/?p=chronodot-rtc. The wiring diagram is the key; software configuration is optional.The wiring will poke outside a standard Raspberry Pi case but the Chronodot itself fits inside nicely.

The chip is an amazing product, and the Macetech board is the best mounting of it for breadboard/small projects. As it comes with a battery, it's a real value. Recommended.

Works great in my Bulbdial clock.