Project Overview

This project utilizes the following components to build a light control system with multiple modes of operation:

Components

• Red Button: Connected to GND and GPIO4
• Blue Button: Connected to GND and GPIO5
• LCD: Connected to GND, 5V, GPIO17 (SCL), GPIO18 (SDA)
• Potentiometer: Middle pin connected to ADC1CH5/PIN6, others to 3V3 and GND
• Photoresistor (LDR):
  • Connected as: 5V --- LDR --- ADC2CH2/PIN13
  • Voltage Divider: LDR connected to a 10KΩ resistor that bridges to GND
• PIR/Motion Sensor:
  • Middle pin connected to GPIO19, others to GND and 5V

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Functionality

Buttons

• Red Button: Cycles through power modes:

  • OFF: Turns off the light but allows adjustments to brightness or light mode.
  • ON: Brightness is controlled using the potentiometer (values mapped from 0-4095 to 0-100%).
  • AUTO: Lights turn on as long as motion is detected (signal HIGH from PIR sensor).
    • The duration of the HIGH signal can be adjusted on the PIR sensor (up to 250 seconds).

• Blue Button: Switches between light modes:

  • COOL WHITE
  • DAYLIGHT
  • NIGHT LIGHT
  • WARM WHITE

Automatic Brightness Adjustment

• In AUTO mode, brightness is determined by the LDR instead of the potentiometer.
• The LDR value reflects ambient light:
  • Values are normalized from 0-4095 to a range of 0-100.
  • Brightness is calculated as 100 - normalized_value.

Example:

• If the LDR detects maximum light (value = 4095):
  • Normalized value = 100.
  • Brightness = 0% (light is dimmed).
• If the LDR detects no light (value = 0):
  • Normalized value = 0.
  • Brightness = 100% (light is fully bright).