What it is and how it works
The kit includes one potentiometer labelled 10 kΩ. Its resistive track has a nominal resistance between its ends. A moving contact, the wiper, touches different points along the track as the shaft turns. Three electrical terminals let it work as an adjustable voltage divider.
With the ends connected to a suitable supply and ground, the wiper voltage changes with rotation. ESP32 converts that voltage into an analogue reading, which software can map to a setting. The 10 kΩ marking is neither a voltage nor a count of rotation steps; it does not establish a perfectly linear response.
What we can use it for
- Choose how quickly an LED blinks.
- Adjust the threshold at which a light sensor triggers an indicator.
- Control a graphic bar or select a value on the OLED.
First exercise
With power disconnected, identify the track ends and wiper using resistance measurements. After correct wiring, watch the reading while slowly turning the shaft. Record the smallest and largest results, then map them to a simple 0–100 scale.
Handling notes
Use 3.3 V for this exercise, never 5 V towards an ESP32 analogue input. Select the ADC pin and range settings for the specific ESP32 variant; a raw reading is not necessarily an accurate voltage measurement. Do not force the shaft beyond its end stops. Here the potentiometer supplies a control signal rather than powering a motor or another large load.
Source: SparkFun — Reading a Potentiometer. Adapt their supply examples to ESP32 logic levels.