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to use the USB cable.
Raspberry Pi A+
doesn’t need to use the pogo pins for back-powering Raspberry Pi,
but the situation changes when integrating with Witty Pi. The pogo pins will also be
used to make sure the USB hub can work in self-power mode, otherwise the USB hub
can only pull power via the upstream USB port, which can only provided very limited
current.
For Raspberry Pi A, B and compute module with development kit
, Witty Pi 2
could not be mounted on them because of the incompatible GPIO pin header. Also
they could not use the pogo pins to power the USB hub, so the USB hub can only
work in bus-power mode. Having all these factors considered,
it doesn’t worth the
effort to put them together.
If you are using Raspberry Pi Zero, and have soldered the 40-pin header on it,
then you can also integrate it with Witty Pi 2 and the USB hub. Just use the pogo pins
to power the USB hub, like we did on model A+, B+ and 2B/3B.
