This is a placeholder topic for “Witty Pi 4 - Realtime Clock and Power Management for Raspberry Pi” comments.
The Witty Pi 4 is an add-on board that adds a real-time clock and power management to your Raspberry Pi. It can define your Raspberry Pi’s ON/OFF sequence…Read more
It says the full size Witty Pi 4 SKU: CE08679 has been replaced by the mini (sized comparatively to the Pi Zero)
Are there any disadvantages to using the mini on a full size Pi? Is it still possible to stack with a 3rd HAT with a USBC cable connected, for example?
I thought the full size Witty Pi and the mini were launched together and one had lesser features?
Welcome to the forum, thanks for posting
The technical specifications are quite similar, the Mini can kick out another 500mA and doesn’t use a coin cell / JST-PH for power but instead appears to use a super-cap but otherwise, they should be nearly identical for use functionally speaking (they both use the same RTC and ATTiny) except, as you’ve noted, the form factor is quite different.
Unfortunately, I don’t have one here to be able to assemble and check the available clearance for you, but as long as you’re using a different I2C address for the other devices on the bus it uses (I believe it is 0x08 by default at the moment) and you’re not drawing excessive load/using the same GPIO as the board for other peripherals (see section 15.3 in the user manual) then you should be good to go assuming that the other boards that you intend to use fit.
All the best with the project and if you have any other questions please feel free to shoot them through.
Thanks for the detailed response! I think it’s also missing the DC-DC converter for higher voltages but that’s fine for me so I think I’ll be going with this mini.
I’m planning to combine this with a 4G HAT, most likely the Waveshare one. It looks like the Witty Pi uses GPIO 2, 3, 4, 14 and 17.
4G HAT also uses 4 and 14. Is this a problem and would it be better to just use a USB modem?
Pretty new to using extra hardware.
That’s a bit of a tricky combo as you can change the default I2C pins the Witty Pi uses but not GPIO pins 4 and 17.
Since Pin 4 may be contested by both HATs you may need to explore a different modem connection.