Zio Ultrasonic Distance Sensor
Ultrasonic distance sensor (20-4000mm range). Uses HC-SR04 with STM8L051 MCU for I2C interface. Ideal for obstacle detection and level measurement.
Say it to PAL
“Tell me when something is in the way.”
The code PAL writes
p.onSensorChange('zio-ultrasonic', 'distance', (dist) => {
if (dist > 0 && dist < 300) p.notify('Object detected at ' + dist + 'mm');
});
await p.waitUntilStopped();“How far away is that?”
The code PAL writes
const dist = await p.read('zio-ultrasonic', 'distance');
if (dist > 0) {
p.log('Distance: ' + dist + 'mm (' + (dist / 10).toFixed(1) + 'cm)');
} else {
p.log('No object in range');
}When to pick it
Use for broad obstacle detection, liquid level measurement, or when you need ultrasonic (not laser) distance sensing. Good complement to VL53L1X for different surface types.
Good to know
- Minimum range is 20mm. Objects closer than 2cm are invisible.
- Soft fabrics and acoustic foam absorb ultrasound — may not detect these surfaces.
- Reading rate is limited by sound travel time (~60ms round trip at 4m).
About it
The Zio Ultrasonic Distance Sensor combines an HC-SR04 ultrasonic transducer with an STM8L051 MCU to provide distance readings over I2C. Measures distances from 20mm to 4000mm (2cm to 4m) using time-of-flight of ultrasonic pulses. Wider beam angle than laser-based sensors (15 degrees), making it better for detecting broad obstacles. Configurable I2C address. Ideal for obstacle detection, liquid level measurement, parking sensors, and room occupancy detection.
Where to buy
Facts
Tested
It is in our catalog, but nobody has checked it on a real board. It may not work yet. Its driver is written, but it has not been tested on hardware yet.
I2C address
The Zio Ultrasonic Distance Sensor answers at I2C address 0x2E. Whether the address can be changed is not recorded in this catalog.
Current
15 mA
The catalog lists a typical draw of 15 mA for the Zio Ultrasonic, copied from the maker’s description and not measured by Palpable.
Board size
45 × 21.54 mm
The Zio Ultrasonic board measures 45 × 21.54 mm and stands 13.6 mm tall with its parts. It has 2 mounting holes. These dimensions are from the maker’s mechanical drawing.
Chips
HC-SR04, STM8L051
Its sensor is the Generic HC-SR04. Its microcontroller is the STMicroelectronics STM8L051.
Free to reuse
Every fact here is open data under CC BY 4.0. Copy it into your own docs or code, and credit Palpable. Download it
This record was last changed on September 20, 2026.