$13 HAT aims Raspberry Pi at real-world I/O projects

Pimoroni’s $13 “Explorer HAT” add-on for the Raspberry Pi can drive motors and touchscreens, integrate sensors, interface with 5V devices, and more.

The Raspberry Pi Foundation’s HAT (Hardware Attached on Top) add-on board standard enables the Linux-ready Raspberry Pi SBC to automatically configure its GPIO signals and drivers for use with external devices. Pimoroni has released Explorer HAT and Explorer HAT Pro models that support the HAT standard on the Raspberry Pi 2 Model B, as well as the first-generation Model B+ and Model A+ boards.




Explorer HAT board (left) and breadboard
(click image to enlarge)

The Explorer HAT provides four buffered 5V inputs for integrating inputs from Arduino boards or 5V Trinkets. There are also four powered 5V outputs supporting delivery of up to 500mA power to stepper motors, solenoids, and relays. The board is further equipped with a mini-breadboard, four LEDs, four capacitive touchpads, and four capacitive alligator clips.


Explorer HAT Pro with breadboard on a Raspberry Pi, bare and encased
(click images to enlarge)

The Explorer HAT Pro offers all these features, and adds analog inputs and a pair of H-bridge motor drivers for driving motors such as micro-metal gear-motors. The Pro version also supplies “a heap of useful (unprotected) 3v3 goodies from the GPIO,” says Pimoroni.


Explorer HAT Pro front (left) and rear views. The touchpads are labeled 1-4 and the clip pads are 5-8.
(click images to enlarge)

Specifications listed for the Explorer HAT include:

• 4x 5V tolerant inputs with 5-channel buffers with 2V-5V support
• 4x powered 5V outputs (darlington array) at up to 500mA per channel (1 Amp total)
• 4x capacitive touch pads on front edge
• 4x capacitive alligator clip pads on side edge
• 4x independently controllable LEDs
• Mini-breadboard
• Weight — 16g without breadboard
• Dimensions — 65 x 56 x 13mm
• Pro version adds:
  • 4x analog inputs
  • 2x H-bridge motor drivers for bidirectional drive of 2x 5V motors at up to 200mA per channel; supports soft-PWM for full speed control
  • Unprotected 3v3 GPIO “goodies”

Further information

The Explorer HAT is available for $12.95 at Adafruit’s Pimoroni Explorer HAT shopping page. More information may be found in Adafruit’s Pimoroni Explorer HAT announcement.

Much the same info may be found at Pimeroni’s own Explorer Hat product page, where you can buy the Explorer Hat for 10 Pounds ($14.80) and the Pro version for 18 Pounds ($26.65). Documentation, examples, and a Python library may be found at the Explorer Hat page on GitHub. GitHub is currently fending off pro-censorship denial of service attacks.