GUIDED BUILD / C++
Build an Arduino distance beacon
Make a tabletop proximity display with an ultrasonic sensor, three LEDs, bounded reads and testable C++ state transitions.
What you will build
A UNO R4 WiFi sketch with explicit unknown echoes, distance bands, hysteresis and rollover-aware scheduling.
The course supplies guided source code and local tests. Board behavior requires your own firmware build and physical validation; these guides do not grant automatic skill mastery.
Before you start
The desktop C++ tests run without a board. The physical sketch targets the 5 V Arduino UNO R4 WiFi and HC-SR04-style module in the Elite Explorer family.
Your build sequence
- 01
Define a useful distance display
Keep measurement units and missing echoes explicit.
- 02
Wire a 5 V UNO R4 experiment
Connect the module and LEDs using an explicit board-specific pin map.
- 03
Test thresholds and hysteresis in C++
Handle invalid measurements before selecting a display band.
- 04
Run a loop with a bounded echo wait
Connect the policy to the Arduino API without claiming a nonblocking sensor driver.
- 05
Measure the physical build
Compare an actual tabletop setup with the nominal conversion.
- 06
Finish a reproducible C++ hardware project
Keep the interface, limits and next scheduling question clear.
- 01Desktop policy tests
- 02Target firmware build
- 03Physical observations
- 04Repeatable project notes
Parts for the physical build
- Arduino UNO R4 WiFi and USB data cable
- HC-SR04-style ultrasonic module supported by the kit guide
- Three LEDs, one 330 Ω resistor per LED, breadboard and jumpers
Existing compatible parts work too. Equipment cards appear in the relevant lessons.