Thanks for sharing this!
Question: Can this RTC be used to delay interrupt pulse signals, or 'stretch' the signal, from a sensor? I should know this, but it's been quite a while since my undergraduate DSP class
If I'm understanding the datasheet correctly, it would seem that this is possible as long as frequency is below a certain frequency.
I'd like to use one of these to modify the signal coming into a Moteino to allow the Moteino enough time to send off a packet without being interrupted on INT1. The pulses are expected to be as short as ~5 ms, but not periodic. Of course, the ATMega328 is perfectly capable of handling this, but I don't think I can put the RFM69 in TX mode, fill the buffer, and send fast enough to handle this.
I've considered using the ATMega's CTC mode to simply poll the pin, but the sleep/wakeup control is appealing as well and I figure it might be easier to have this all taken care of by this RTC.