Power Requirements for the Prototype Pocket Mesh
The Raspberry Pi 3 requires 2.5 amps of power at 5 volts for normal operation.
The core problem with the pmesh’s power system at the moment is that the pi has zero internal power management support, and powers up as soon as power is detected at the inputs.
Since the battery control board we have applies power as soon as it detects a closed circuit, we have a boot loop that we can’t stop, meaning we can never really shut the pmesh ‘off’.
This is a problem.
What the power system should look like -
- First and formost, graceful shutdown on low battery. This requires detecting low battery, and acting on it.
This is a solved problem. we have developed a circuit and a rough code base to allow the pi to monitor the batterypack, and engage in a controlled shutdown.
- A hibernation mode would be desirable.
This probably isn’t happening.
- Wake on lan would also be a desirable feature.
I see no way to implement this with the tools and parts we have access to.
But graceful shutdown on low battery is an absolute must. otherwise, the SD-cards will constantly get corrupted.