Question 1

How to wire HC-SR04 to a MicroPython board?

Accepted Answer

Connect the HC-SR04's VCC, GND, trigger, and echo pins to your board's power and GPIO pins. In code, specify the trigger and echo pin numbers when creating the HCSR04 object, as shown in the README examples.

Question 2

What's the difference between distance_cm and distance_mm methods?

Accepted Answer

`distance_cm()` returns a float in centimeters, using floating-point operations. `distance_mm()` returns an integer in millimeters without floating-point, ideal for systems lacking FPU support, such as some low-end microcontrollers.

Question 3

Why does my sensor keep throwing 'Out of range' errors?

Accepted Answer

This error occurs when the echo signal times out, often due to objects beyond the sensor's range (default 4m limit), incorrect wiring, or environmental interference. Adjust the `echo_timeout_us` parameter or check connections.

Question 4

Micropython hcsr04 driver vs other MicroPython ultrasonic libraries: which is better?

Accepted Answer

This driver uses `machine.time_pulse_us()` for better accuracy and offers integer-only calculation, but other libraries might have more features or broader sensor support. Choose based on your need for precision and resource constraints.

Question 5

How to use multiple HC-SR04 sensors with this driver?

Accepted Answer

Instantiate separate HCSR04 objects for each sensor with unique trigger and echo pin assignments. Ensure your board has sufficient GPIO pins and manage timing to prevent signal interference between sensors.

Question 6

Does this driver work with ESP32 or Raspberry Pi Pico?

Accepted Answer

Yes, it should work with any MicroPython-compatible board like ESP32 or Raspberry Pi Pico, as it relies on standard MicroPython APIs without hardware-specific code, but test for compatibility as noted in the README.

Question 7

How to improve distance measurement accuracy in noisy environments?

Accepted Answer

Use the integer `distance_mm()` method to reduce floating-point errors, ensure stable power supply, and consider averaging multiple readings or adding external shielding. The driver's configurable timeout can help adjust for range limits.

micropython-hcsr04

What is micropython-hcsr04?

Overview

Use Cases

Best For

Found a gem we're missing?

Not Ideal For

Pros & Cons

Pros

Cons

Frequently Asked Questions