The PiTopping Board snaps onto your Raspberry Pi and is controlled using the GPIO pins (it uses only the RS232 Tx and Rx pins, all other GPIO pins are re-exposed and usable). With the PiTopping, you have the following added abilities:
Eight analog or digital sensor ports. You get a basic set of sensors with the PiTopping kit, but you can always get more from places such as SEEED studio.
Four servo or DC motor ports. You can also use these ports to activate lights and relays as well.
Infrared remote control receiver. The PiTopping understands the codes from any SONY remote control.
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