Kookabus

I²C boards for machines that run on real batteries.

Hot-swap power, servo drive and sensing on one 4-pin bus. Works with Qwiic and PiicoDev. Designed in Australia.

The boards

Each board has its own site with the full technical detail: specifications, connectors, addresses and code.

Kookabus-01

Dual 5S hot-swap battery board

Available 25 October 2026AUD $59

Two 5S packs in, one load out, 100 W peak. Pull a pack and the load never notices. Bus voltage, current and power come back over I²C from an INA226, so your code knows when it is time to swap.

Open the Kookabus-01 site
Kookabus-02

Serial bus servo driver

Coming soon

Drives up to four ST3215 digital servos, or any compatible serial bus servo, from the same I²C connector. Position, speed and load feedback come back over the bus.

See what is planned

One connector across the family

Every Kookabus board carries two 4-pin bus connectors, so boards chain from one to the next and back to your controller.

YOUR CONTROLLER Pi, Pico, Arduino KOOKABUS-01 ADDR A0 A1 KOOKABUS-02 ADDR A0 A1 GND 3V3 SDA SCL

The connector is the 4-pin JST-SH 1.0 mm used by PiicoDev and Qwiic, with the same pin order, so the boards plug straight into those ecosystems and their cables.

Signals
GND, 3.3 V, SDA, SCL. Logic is 3.3 V.
Chaining
Two connectors per board. Cable in on one, out to the next on the other.
Addressing
Solder jumpers A0 and A1 on each board select its I²C address, so several of the same board share a bus.
Pull-ups
Boards ship with 4.7 kΩ pull-ups on. Cut the PU jumper on all but one board per bus, or on all of them if the host has its own.