Why the Cruiser Has Qwiic Instead of RS-485

The Interceptor had RS-485. The Cruiser doesn’t. If that sounds like we removed a feature, keep reading.
By Exaviz Team |
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The Interceptor had RS-485. The Cruiser doesn’t.

If that sounds like we removed a feature, keep reading.

RS-485 is a serial bus. It connects one class of device: industrial controllers, sensors with serial output, Modbus equipment. It requires custom wiring, termination resistors, and possibly an oscilloscope when things go wrong.

The Cruiser has two Qwiic ports instead.

Qwiic is a standardized I2C connector. A 4-pin JST plug shared by SparkFun Electronics, Adafruit Industries (STEMMA QT), and dozens of other manufacturers. No soldering, no termination, no wiring. Click it in. It works. And the ecosystem has hundreds of modules.

Here’s the part some people may miss: because Qwiic carries I2C, it opens the door to I2C-to-UART bridge hardware that supports RS-485 signaling. The capability isn’t gone. It’s one adapter away instead of being hard-wired to a single protocol. And now you also get access to everything else.

What “everything else” looks like:

  • A Qwiic Single Relay ($18, SparkFun). Switch a 240VAC / 5.5A circuit over I2C. Lighting, irrigation, garage doors, HVAC. Controllable from Home Assistant.
  • An SCD-40 true CO2 sensor ($45, Adafruit). Server room or grow tent air quality monitoring with temperature and humidity. Automated alerts when ventilation fails.
  • An MCP9601 thermocouple amplifier ($15, Adafruit). Read K, J, T, N, S, E, B, and R type thermocouples over I2C. 3D printer enclosures, kilns, HVAC ducts.
  • A Qwiic Scale with NAU7802 ADC ($18.50, SparkFun). 24-bit load cell measurements. Propane tank level, beehive weight, package detection.
  • A PA1010D GPS module ($30, Adafruit). Precision location and time over I2C. Asset tracking, NTP time source, geofencing.
  • A 128x32 OLED display ($12.50, Adafruit). Mount it on your rack enclosure and show live PoE power draw per port, system uptime, IP address.

One of the first things a hardware integrator asked us for on the Interceptor was GPIO and I2C access. It would have required a custom add-on board. On the Cruiser, it’s two Qwiic ports, built in. Voltage selectable between 3.3V and 5V. Daisy-chainable.

We didn’t remove a feature. We replaced one protocol with an ecosystem.

Oh, and the Cruiser’s Qwiic ports are also compatible with Adafruit’s STEMMA QT connector. But that’s a post for another day.

Full specs and pre-order at exaviz.com. Documentation at exa-pedia.com.

(Photo Courtesy of Jeff Geerling)

Last modified March 4, 2026