RTC with the ability to wake the CM4

I finally have a CM4 for my IO board - CM4-IO-WIRELESS-BASE - Waveshare Wiki

It looks like it has much of the same features and parts as the official io board:

It mentions on the link above that the official board has a RTC with the ability to wake the pi (same as the waveshare wireless io one). That’s my goal here, to schedule tasks, shutdown, and wake up on the RTC alarm to repeat.

What I’ve got from support at waveshare so far is that I need to “solder a 0R resistor to GL-EN”

So far I have it detecting the RTC and can sync the time from the system clock, display the time from the hardware clock, etc, but can’t seem to find ANY documentation on how to program the alarm? The closest thing I’ve found is this:

It looks like it was written for something called the Alarm Pi board from AB Electronics, and uses rtc-pcf8563. Is this the same as the PCF85063AT on the official io board and my waveshare one? For anyone who can point me in the right direction, thank you!

Hi Lewis,

Looks like a generous maker has written a python library for the RTC chip on this board:

Give that a look and let us know how you go!


@Lewis -did this solution work for you? I am trying to achieve exactly the same thing.
Also, does it work with camera enabled? I was told by Waveshare that the CM4 IO board RTC will not work alongside active camera. If I want to use an RTC, cannot use camera. Is this true in your experience?

I actually gave up with that board unfortunately. I asked someone from waveshare IIRC and they said something about soldering a 0R resistor somewhere to get it to work the way I wanted. I ended up using WittyPi and it’s so much easier. I also wasn’t using the Pi camera, but yes, maybe there is a conflict with the pi camera, not sure about that.

I’m actually using the Pi with DSLR/gphoto2