firmware-base/docs-c/components/LEDFeedback.md

title	description	keywords
LED Feedback Component Documentation	Documentation for the LED Feedback component providing visual status indicators using addressable LED strips	LED Feedback, NeoPixel, WS2812B, SK6812, ESP32, visual indicator

LED Feedback

Path: src/LEDFeedback.cpp

Revision History: Initial documentation

The LED Feedback component provides visual status indication through addressable LED strips (NeoPixel compatible). It offers multiple display modes including fading effects, level indicators, and tri-color blinking patterns that can be controlled via Modbus.

REQUIREMENTS

• Digital output pin connected to WS2812B/SK6812 compatible LED strip
• 5V power supply for the LED strip (separate from microcontroller logic)
• Modbus TCP connection for remote control

FEATURES

• Multiple display modes:
  • OFF: All LEDs turned off
  • FADE_R_B: Smooth color transition between red and blue
  • RANGE: Level indicator (0-100%) using lit LEDs
  • TRI_COLOR_BLINK: Three-section traffic light style blinking (red, yellow, green)
• Modbus control interface for mode selection and parameters
• Adjustable update rate for animations
• Configurable pixel count to support different strip lengths

DEPENDENCIES

• Adafruit_NeoPixel - Library for controlling addressable LED strips
• ArduinoLog - Logging functionality
• ModbusTCP - For Modbus communication

graph TD
    LEDFeedback --> Component
    LEDFeedback --> Adafruit_NeoPixel
    LEDFeedback --> ModbusTCP
    LEDFeedback --> ArduinoLog
    LEDFeedback --> Bridge

BEHAVIOUR

stateDiagram-v2
    [*] --> OFF
    OFF --> FADE_R_B: Modbus write mode=1
    OFF --> RANGE: Modbus write mode=2
    OFF --> TRI_COLOR_BLINK: Modbus write mode=3
    
    FADE_R_B --> OFF: Modbus write mode=0
    FADE_R_B --> RANGE: Modbus write mode=2
    FADE_R_B --> TRI_COLOR_BLINK: Modbus write mode=3
    
    RANGE --> OFF: Modbus write mode=0
    RANGE --> FADE_R_B: Modbus write mode=1
    RANGE --> TRI_COLOR_BLINK: Modbus write mode=3
    RANGE: Update level via Modbus
    
    TRI_COLOR_BLINK --> OFF: Modbus write mode=0
    TRI_COLOR_BLINK --> FADE_R_B: Modbus write mode=1
    TRI_COLOR_BLINK --> RANGE: Modbus write mode=2

TODOS

PERFORMANCE

• Consider power consumption optimization for battery-powered applications
• Investigate using DMA-based LED control to reduce CPU usage
• Add brightness control via Modbus to manage power usage

SECURITY

• Validate Modbus values more strictly to prevent unexpected behavior
• Consider adding access control for mode changes

COMPLIANCE

• Verify EMC compliance when LEDs change rapidly (potential for EMI)
• Ensure ADA compliance for visual indicators in public/commercial settings

RECOMMENDATIONS

• Use adequate power supply for LED strips (60mA per pixel at full brightness)
• Consider adding a level-shifting circuit when connecting 3.3V microcontrollers to 5V LED strips
• Add physical protection for LEDs in industrial environments
• Implement custom modes for specific application requirements

EXAMPLE

This example shows how to initialize and mount an LED Feedback component in an application:

#ifdef PIN_LED_FEEDBACK_0
  ledFeedback_0 = new LEDFeedback(
      this,                  // owner
      PIN_LED_FEEDBACK_0,    // pin
      LED_PIXEL_COUNT_0,     // pixelCount
      ID_LED_FEEDBACK_0,     // id
      LED_FEEDBACK_0_MB_ADDR // modbusAddress
  );
  if (ledFeedback_0)
  {
    components.push_back(ledFeedback_0);
    Log.infoln(F("LEDFeedback_0 initialized. Pin:%d, Count:%d, ID:%d, MB:%d"),
               PIN_LED_FEEDBACK_0, LED_PIXEL_COUNT_0,
               ID_LED_FEEDBACK_0, LED_FEEDBACK_0_MB_ADDR);
  }
  else
  {
    Log.errorln(F("LEDFeedback_0 initialization failed."));
  }
#endif

References