but SOIC package only it seems. I have a project where I really want to avoid using SM devices as other people will be building them.
"I was planning to feed the 1Hz output from SQW to timer/counter2 in order to wake the Arduino from sleep mode every 20 or 30 seconds."Won't that wake it every second? Or will you increment a counter every time, and when high enough, then do something?
#define PIN_TC2 15
The DS3231 is easier to solder than you think...most of the pins are connected to ground. So much good stuff comes in SOIC and smaller, that I think any serious electronics experimenter should have some SMT breakouts and be able to do drag soldering. I actually prefer SMT to through-hole for hand assembly.