The Raspberry Pi is a pretty capable device that has been the foundation of countless projects. However, it’s not without flaws. Namely, the power management capabilities. There’s also scenarios where the device isn’t easily reached, and when RPIs crash, it’s a headache to reset the device.
While the included hardware can reset a Pi, it doesn’t possess the ability to turn it off and on again. There’s no way to completely power down a Raspberry Pi, it’s always pulling power in some form. The owner of South Berkeley Electronics had this problem when they were setting up Raspberry Pi-based cameras around a campus.
The solar-powered solutions worked great, but they soon ran into issues with low light conditions and outages throughout the network. This required manually resetting the Pis, which was neither fun nor efficient.
That’s when they got the idea for the PiDog2. This handy hat for Raspberry PI has the ability to cut power from the Pi after a set period of time. It also has the ability to power up the device as well. Finally, it can provide the Pi with a measurement of the 5V and 3.3V supplies, along with two other voltages of your choosing.
The result? Your software can make choices about when to shut down and save battery or avoid flash corruption. The PiDog2 will wake up or boot the Pi again periodically and decide if it’s best to power back down or operate normally.
The PiDog2 is powered by an ATtiny84 microcontroller connected to the Pi via the GPIO header and the SPI interface. You can still use other SPI devices that work off other chip selects. A Python library allows you to interact with the registers, and a good portion of the soldering is already done when you receive the kit.
