Add support for PCF8523 alarms

[VallesMarinerisExplorer]

Hi RTClib,

I have an adafruit data logger shield with the PCF8523 and I want to wake up my arduino by sending a signal from the interrupt pin on the RTC. I have been looking at the example for the DS3231 for an alarm and trying to adapt the code for the PCF8523, but there are no alarm functions for the PCF8523. Is it possible to use the PCF8523 to create an alarm or am I limited by the hardware and should just get a DS3231?

Thanks!

Alex

[edgar-bonet]

The PCF8523 does have an alarm mode, but it is not supported by RTClib. You could try to implement that support yourself, based on the datasheet of that RTC. Alternatively, depending on your timing requirements, the countdown timer may be usable, and it is supported by the library.