Example 14: RGB NeoPixel (WS2812B)

Experiment Overview

Drive WS2812B (NeoPixel) RGB LEDs via single-wire protocol for full-color control. FastBee has a built-in NEO_PIXEL peripheral type (type: 45), supporting color, brightness and LED count settings.

Hardware Wiring

Board Label	GPIO Pin	Connected Device
DATA	GPIO4	WS2812B data pin (DIN)

WS2812B power supply recommends 5V, data line can connect directly to 3.3V GPIO (most WS2812B are compatible).

JSON Configuration Example

{
  "peripherals": [
    {
      "id": "ws2812b",
      "name": "WS2812B RGB LED",
      "type": 45,
      "enabled": false,
      "pins": [4],
      "params": {
        "count": 8,
        "brightness": 64
      }
    }
  ]
}

Parameter Description

Parameter	Description	Range
count	Number of LEDs	1~255
brightness	Global brightness	0~255

Peripheral Execution Linkage

Scenario 1: Set Single LED Color (Platform Trigger)

Function: Set LED #0 to red via cloud platform command

Web Interface Configuration Steps

Step 1: Create Rule

1. Click left menu Peripheral Configuration → Switch to Peripheral Execution Management tab
2. Click New Rule button
3. Fill in basic configuration:
   • Rule Name: Set RGB Color
   • Report Data: ✅ Enable
   • Enabled: ✅ Enable

Step 2: Configure Trigger

1. Click Add Trigger button

2. Fill in trigger configuration:

   Field	Value	Description
   Trigger Type	Select Platform Trigger	Receive cloud platform commands
   Operator	Select Match Pattern	Match command
   Comparison Value	{"cmd":"color"}	Color control command

Step 3: Configure Action

1. Click Add Action button

2. Fill in:

   • Action Type: Select Set RGB
   • Target Peripheral: Select ws2812b
   • LED Index: 0 (LED #0)
   • R Value: 255
   • G Value: 0
   • B Value: 0

3. Click Save button

---

Scenario 2: Set All to Same Color (Platform Trigger)

Function: Set all LEDs to green via cloud platform command

Web Interface Configuration Steps

1. Create rule, name: All Green
2. Trigger configuration:
   • Trigger Type: Select Platform Trigger
   • Operator: Select Match Pattern
   • Comparison Value: {"cmd":"all_green"}
3. Action configuration:
   • Action Type: Select Fill RGB
   • Target Peripheral: Select ws2812b
   • R Value: 0
   • G Value: 255
   • B Value: 0
4. Click Save

Common RGB Color Values

Color	R	G	B	Description
Red	255	0	0	Pure red
Green	0	255	0	Pure green
Blue	0	0	255	Pure blue
White	255	255	255	White
Yellow	255	255	0	Yellow
Purple	255	0	255	Purple
Cyan	0	255	255	Cyan

Notes

1. Power: Each WS2812B draws ~60mA at full brightness, multiple LEDs need independent 5V power
2. Level: Some WS2812B need 5V logic level, add level shifting or 330Ω resistor in series on DIN
3. Timing Sensitive: WS2812B has strict timing requirements, recommend using RMT peripheral (ESP32 uses it by default)
4. Refresh Rate: More LEDs = slower refresh, 100 LEDs ~3ms
5. Data Order: Color order may be GRB instead of RGB, depending on model