Tag Archives: neoPixel

In this exciting lesson, we build a real-time Emotion Detector that can recognize basic human emotions using just a Raspberry Pi, a camera, and the power of MediaPipe. The system watches your face and identifies whether you look Neutral, Smiling, Surprised, or Angry — and then reacts instantly by changing the color of a NeoPixel ring and displaying the detected emotion on both the camera preview and a small OLED display.Using MediaPipe’s Face Mesh solution, the program tracks 468 facial landmarks in real time. From these points, we carefully calculate key facial ratios — such as eye openness, mouth width, and mouth height relative to head width. These measurements allow us to create simple but effective rules that distinguish between different emotional expressions. For example, a wide mouth combined with raised cheeks indicates a smile, while a small mouth opening and narrowed eyes suggests anger.The project beautifully integrates several powerful technologies:

Picamera2 for high-performance camera capture
OpenCV for image processing and on-screen text display
MediaPipe Face Mesh for accurate facial landmark detection
NeoPixel RGB ring that lights up in different colors depending on the detected emotion
SSD1306 OLED display that shows both the emotion name and a simplified wireframe of your face

One of the most satisfying parts of this project is seeing the NeoPixel ring instantly change color to match your emotion — green for happy, cyan for surprised, red for angry, and yellow for neutral. The OLED also mirrors the detected emotion, making the entire system feel alive and responsive.This lesson is a fantastic step forward in understanding how to combine computer vision with physical outputs on the edge. You will learn how to extract meaningful measurements from facial landmarks, build rule-based emotion logic, and synchronize visual feedback across multiple devices (camera preview, NeoPixel, and OLED).By the end of Lesson 47, you will have a working real-time emotion recognition system running entirely on a Raspberry Pi — a great foundation for more advanced projects like mood-reactive lights, interactive robots, or even assistive technology.

# ====================================================================
# DISCLAIMER:
# This code is provided as-is for educational and experimental 
# purposes only. The author makes no representations or warranties of 
# any kind concerning the safety, suitability, or accuracy of this 
# code. Use at your own risk. The author assumes no liability for any 
# damages, system failures, security breaches, or network issues 
# resulting from the use or implementation of this script.
# ====================================================================

import cv2
import time
from picamera2 import Picamera2
import mediapipe as mp
import numpy as np
#################################
import board
import adafruit_ssd1306
from PIL import Image, ImageDraw, ImageFont
import time

import neopixel_spi as neopixel
import colorsys
spi=board.SPI()
LC = 12
PO = neopixel.GRB
strip = neopixel.NeoPixel_SPI(spi, LC,
            pixel_order=PO,auto_write=False)
strip.fill(0)
strip.show()

wOLED = 128
hOLED = 64
I2C_ADDRESS = 0x3C
i2c = board.I2C()
oled = adafruit_ssd1306.SSD1306_I2C(wOLED, hOLED, i2c, addr = I2C_ADDRESS)
fontLarge = ImageFont.truetype("/usr/share/fonts/truetype/dejavu/DejaVuSans-Bold.ttf",14)
#################################
W=1280
H=720
tStart = time.time()
fps = 0

piCam = Picamera2(1)
piCam.preview_configuration.main.size = (W, H)
piCam.preview_configuration.main.format = "RGB888"
piCam.preview_configuration.controls.FrameRate = 60
piCam.preview_configuration.align()
piCam.configure("preview")
piCam.start()

textLowerLeft = (int(W*.01),int(H*.05))
fontFace = cv2.FONT_HERSHEY_SIMPLEX
fontThickness = int(W/425)
fontScale = H*.0015
fontColor = (0,0,255)

faceMesh = mp.solutions.face_mesh.FaceMesh(
    
    max_num_faces=1,
    refine_landmarks=True,
    min_detection_confidence=0.5,
    min_tracking_confidence=0.5)

cv2.namedWindow('Camera',cv2.WINDOW_GUI_NORMAL)
cv2.moveWindow('Camera',0,65)
cv2.resizeWindow('Camera',W,H)
while True:
    deltaT = time.time() - tStart
    tStart=time.time()
    fps = fps*.95 + (1/deltaT)*.05
    frame = piCam.capture_array()
    frame = cv2.flip(frame, -1)

    rgb = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
    results = faceMesh.process(rgb)
    
    if results.multi_face_landmarks:
        for faceLandMarks in results.multi_face_landmarks:
            #print(faceLandmarks)
            image = Image.new("1",(wOLED,hOLED))
            draw = ImageDraw.Draw(image)
            lmAll = []
            j=0
            for lm in faceLandMarks.landmark:
                xOLED = int(lm.x*wOLED)
                yOLED = int(lm.y*hOLED)
                draw.point((xOLED,yOLED), fill = 255)
                #print(xOLED,yOLED)
                lmAll.append((xOLED,yOLED))
                x = int(lm.x*W)
                y = int(lm.y*H)
                #cv2.putText(frame,str(j),(x,y),fontFace, .3, (0,255,0),1)
                j = j+1
            for idx in mp.solutions.face_mesh.FACEMESH_CONTOURS:
                #print(idx)
                lineStart = idx[0]
                lineEnd = idx[1]
                pt1 = lmAll[lineStart]
                pt2 = lmAll[lineEnd]
                draw.line((pt1[0],pt1[1],pt2[0],pt2[1]), width=1, fill = 255)

            keyLM = faceLandMarks.landmark
            
            headRight = 323
            headLeft = 93
            headWidth = keyLM[headRight].x -keyLM[headLeft].x
            cv2.putText(frame,str(headRight),(int(keyLM[headRight].x*W),int(keyLM[headRight].y*H)),fontFace, .3, (0,255,0),1)
            cv2.putText(frame,str(headLeft),(int(keyLM[headLeft].x*W),int(keyLM[headLeft].y*H)),fontFace, .3, (0,255,0),1)
            
            leftEyeTop = 159
            leftEyeBottom = 145
            leftEyeHeight =keyLM[leftEyeBottom].y -keyLM[leftEyeTop].y
            leftEyeLeft = 130
            leftEyeRight = 154
            leftEyeWidth = keyLM[leftEyeRight].x -keyLM[leftEyeLeft].x
            leftEyeRatio = leftEyeHeight/leftEyeWidth*100 
            
            rightEyeTop = 385
            rightEyeBottom = 253
            rightEyeHeight = keyLM[rightEyeBottom].y -keyLM[rightEyeTop].y
            rightEyeLeft = 465
            rightEyeRight = 249
            rightEyeWidth = keyLM[rightEyeRight].x -keyLM[rightEyeLeft].x
            rightEyeRatio = rightEyeHeight/rightEyeWidth*100
            
            eyeRatio = (rightEyeRatio +leftEyeRatio)/2
            
            mouthLeft = 61
            mouthRight = 291
            mouthTop = 13
            mouthBottom = 15
            mouthWidth = keyLM[mouthRight].x-keyLM[mouthLeft].x
            mouthHeight = keyLM[mouthBottom].y-keyLM[mouthTop].y
            mouthWidthRatio = mouthWidth/headWidth *100
            mouthHeightRatio = mouthHeight/headWidth*100
            
            print(round(mouthWidthRatio,1),round(mouthHeightRatio,1),round(eyeRatio,1))
            color = (255,255,0)
            emotion = 'NEUTRAL'
            if mouthWidthRatio >37 and mouthHeightRatio>4 and eyeRatio<74:
                emotion = 'SMILE'
                color = (0,255,0)
            if mouthWidthRatio <37 and mouthHeightRatio>10 and eyeRatio>70:
                emotion = 'SURPRISED'
                color = (0,255,255)
            if mouthWidthRatio <32 and mouthHeightRatio<4 and eyeRatio<57:
                emotion = 'ANGRY'
                color = (0,0,255)               
            cv2.putText(frame, emotion, (int(W*.1),int(H*.15)),
                    fontFace, 2.2, color, 4)
            strip.fill((color[2],color[1],color[0]))
            strip.show()
            #print('XXXXXXXXXXXXXXXXXXx')
            draw.text((0,0),emotion,font=fontLarge,fill=255)
            oled.image(image)
            oled.show()
        #print()

#     if results.multi_face_landmarks:
#         for faceLandmarks in results.multi_face_landmarks:
#             # Optional second pass for glow effect
#             mp.solutions.drawing_utils.draw_landmarks(
#                 image=frame,
#                 landmark_list=faceLandmarks,
#                 connections=mp.solutions.face_mesh.FACEMESH_TESSELATION,
#                 landmark_drawing_spec=None,
#                 connection_drawing_spec=mp.solutions.drawing_utils.DrawingSpec(
#                     color=(100, 100, 100),
#                     thickness=1
#                 )
#             )
#             # === Best looking translucent mesh ===
#             mp.solutions.drawing_utils.draw_landmarks(
#                 image=frame,
#                 landmark_list=faceLandmarks,
#                 connections=mp.solutions.face_mesh.FACEMESH_CONTOURS,
#                 landmark_drawing_spec=None,                    # Hide dots
#                 connection_drawing_spec=mp.solutions.drawing_utils.DrawingSpec(
#                     color=(0, 0, 180),      # Bright cyan/teal
#                     thickness=7
#                 )
#             )
# 
#             # Optional: Extra detail on irises (makes eyes look better)
#             mp.solutions.drawing_utils.draw_landmarks(
#                 image=frame,
#                 landmark_list=faceLandmarks,
#                 connections=mp.solutions.face_mesh.FACEMESH_IRISES,
#                 landmark_drawing_spec=None,
#                 connection_drawing_spec=mp.solutions.drawing_utils.DrawingSpec(
#                     color=(255, 0, 0),
#                     thickness=7
#                 )
#             )

    myText = "FPS: "+str(round(fps,1))
    cv2.putText(frame,myText,textLowerLeft,fontFace,fontScale,fontColor,fontThickness)

    cv2.imshow("Camera", frame)

    if cv2.waitKey(1) == ord('q'):
        break

cv2.destroyAllWindows()
piCam.stop()
oled.fill(0)
oled.show()
strip.fill(0)
strip.show()

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# ====================================================================

# DISCLAIMER:

# This code is provided as-is for educational and experimental

# purposes only. The author makes no representations or warranties of

# any kind concerning the safety, suitability, or accuracy of this

# code. Use at your own risk. The author assumes no liability for any

# damages, system failures, security breaches, or network issues

# resulting from the use or implementation of this script.

# ====================================================================

import cv2

import time

from picamera2 import Picamera2

import mediapipe as mp

import numpy as np

#################################

import board

import adafruit_ssd1306

from PIL import Image, ImageDraw, ImageFont

import time

import neopixel_spi as neopixel

import colorsys

spi=board.SPI()

LC = 12

PO = neopixel.GRB

strip = neopixel.NeoPixel_SPI(spi, LC,

pixel_order=PO,auto_write=False)

strip.fill(0)

strip.show()

wOLED = 128

hOLED = 64

I2C_ADDRESS = 0x3C

i2c = board.I2C()

oled = adafruit_ssd1306.SSD1306_I2C(wOLED, hOLED, i2c, addr = I2C_ADDRESS)

fontLarge = ImageFont.truetype("/usr/share/fonts/truetype/dejavu/DejaVuSans-Bold.ttf",14)

#################################

W=1280

H=720

tStart = time.time()

fps = 0

piCam = Picamera2(1)

piCam.preview_configuration.main.size = (W, H)

piCam.preview_configuration.main.format = "RGB888"

piCam.preview_configuration.controls.FrameRate = 60

piCam.preview_configuration.align()

piCam.configure("preview")

piCam.start()

textLowerLeft = (int(W*.01),int(H*.05))

fontFace = cv2.FONT_HERSHEY_SIMPLEX

fontThickness = int(W/425)

fontScale = H*.0015

fontColor = (0,0,255)

faceMesh = mp.solutions.face_mesh.FaceMesh(

max_num_faces=1,

refine_landmarks=True,

min_detection_confidence=0.5,

min_tracking_confidence=0.5)

cv2.namedWindow('Camera',cv2.WINDOW_GUI_NORMAL)

cv2.moveWindow('Camera',0,65)

cv2.resizeWindow('Camera',W,H)

while True:

deltaT = time.time() - tStart

tStart=time.time()

fps = fps*.95 + (1/deltaT)*.05

frame = piCam.capture_array()

frame = cv2.flip(frame, -1)

rgb = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)

results = faceMesh.process(rgb)

if results.multi_face_landmarks:

for faceLandMarks in results.multi_face_landmarks:

#print(faceLandmarks)

image = Image.new("1",(wOLED,hOLED))

draw = ImageDraw.Draw(image)

lmAll = []

j=0

for lm in faceLandMarks.landmark:

xOLED = int(lm.x*wOLED)

yOLED = int(lm.y*hOLED)

draw.point((xOLED,yOLED), fill = 255)

#print(xOLED,yOLED)

lmAll.append((xOLED,yOLED))

x = int(lm.x*W)

y = int(lm.y*H)

#cv2.putText(frame,str(j),(x,y),fontFace, .3, (0,255,0),1)

j = j+1

for idx in mp.solutions.face_mesh.FACEMESH_CONTOURS:

#print(idx)

lineStart = idx[0]

lineEnd = idx[1]

pt1 = lmAll[lineStart]

pt2 = lmAll[lineEnd]

draw.line((pt1[0],pt1[1],pt2[0],pt2[1]), width=1, fill = 255)

keyLM = faceLandMarks.landmark

headRight = 323

headLeft = 93

headWidth = keyLM[headRight].x -keyLM[headLeft].x

cv2.putText(frame,str(headRight),(int(keyLM[headRight].x*W),int(keyLM[headRight].y*H)),fontFace, .3, (0,255,0),1)

cv2.putText(frame,str(headLeft),(int(keyLM[headLeft].x*W),int(keyLM[headLeft].y*H)),fontFace, .3, (0,255,0),1)

leftEyeTop = 159

leftEyeBottom = 145

leftEyeHeight =keyLM[leftEyeBottom].y -keyLM[leftEyeTop].y

leftEyeLeft = 130

leftEyeRight = 154

leftEyeWidth = keyLM[leftEyeRight].x -keyLM[leftEyeLeft].x

leftEyeRatio = leftEyeHeight/leftEyeWidth*100

rightEyeTop = 385

rightEyeBottom = 253

rightEyeHeight = keyLM[rightEyeBottom].y -keyLM[rightEyeTop].y

rightEyeLeft = 465

rightEyeRight = 249

rightEyeWidth = keyLM[rightEyeRight].x -keyLM[rightEyeLeft].x

rightEyeRatio = rightEyeHeight/rightEyeWidth*100

eyeRatio = (rightEyeRatio +leftEyeRatio)/2

mouthLeft = 61

mouthRight = 291

mouthTop = 13

mouthBottom = 15

mouthWidth = keyLM[mouthRight].x-keyLM[mouthLeft].x

mouthHeight = keyLM[mouthBottom].y-keyLM[mouthTop].y

mouthWidthRatio = mouthWidth/headWidth *100

mouthHeightRatio = mouthHeight/headWidth*100

print(round(mouthWidthRatio,1),round(mouthHeightRatio,1),round(eyeRatio,1))

color = (255,255,0)

emotion = 'NEUTRAL'

if mouthWidthRatio >37 and mouthHeightRatio>4 and eyeRatio<74:

emotion = 'SMILE'

color = (0,255,0)

if mouthWidthRatio <37 and mouthHeightRatio>10 and eyeRatio>70:

emotion = 'SURPRISED'

color = (0,255,255)

if mouthWidthRatio <32 and mouthHeightRatio<4 and eyeRatio<57:

emotion = 'ANGRY'

color = (0,0,255)

cv2.putText(frame, emotion, (int(W*.1),int(H*.15)),

fontFace, 2.2, color, 4)

strip.fill((color[2],color[1],color[0]))

strip.show()

#print('XXXXXXXXXXXXXXXXXXx')

draw.text((0,0),emotion,font=fontLarge,fill=255)

oled.image(image)

oled.show()

#print()

# if results.multi_face_landmarks:

# for faceLandmarks in results.multi_face_landmarks:

# # Optional second pass for glow effect

# mp.solutions.drawing_utils.draw_landmarks(

# image=frame,

# landmark_list=faceLandmarks,

# connections=mp.solutions.face_mesh.FACEMESH_TESSELATION,

# landmark_drawing_spec=None,

# connection_drawing_spec=mp.solutions.drawing_utils.DrawingSpec(

# color=(100, 100, 100),

# thickness=1

# )

# # === Best looking translucent mesh ===

# mp.solutions.drawing_utils.draw_landmarks(

# image=frame,

# landmark_list=faceLandmarks,

# connections=mp.solutions.face_mesh.FACEMESH_CONTOURS,

# landmark_drawing_spec=None, # Hide dots

# connection_drawing_spec=mp.solutions.drawing_utils.DrawingSpec(

# color=(0, 0, 180), # Bright cyan/teal

# thickness=7

# )

# # Optional: Extra detail on irises (makes eyes look better)

# mp.solutions.drawing_utils.draw_landmarks(

# image=frame,

# landmark_list=faceLandmarks,

# connections=mp.solutions.face_mesh.FACEMESH_IRISES,

# landmark_drawing_spec=None,

# connection_drawing_spec=mp.solutions.drawing_utils.DrawingSpec(

# color=(255, 0, 0),

# thickness=7

# )

myText = "FPS: "+str(round(fps,1))

cv2.putText(frame,myText,textLowerLeft,fontFace,fontScale,fontColor,fontThickness)

cv2.imshow("Camera", frame)

if cv2.waitKey(1) == ord('q'):

break

cv2.destroyAllWindows()

piCam.stop()

oled.fill(0)

oled.show()

strip.fill(0)

strip.show()

These are the schematics we are using for todays project. If you are taking the class, you should already have these components connected:

Fusion Hat Circuit Diagram — This is the circuit we will use moving forward in the class

SSD1306 OLED Connected to the Fusion AI Hat

AI On the Edge, Raspberry Pi

AI on the Edge LESSON 45: Adding a NeoPixel Ring To Your Raspberry Pi Project

August 26, 2026 admin

In Lesson 45 of our AI on the Edge series, we take our Fusion AI Lab Kit to the next level by adding a 12-pixel NeoPixel ring. This lesson bridges the gap between pure AI processing and vibrant physical output, showing how your edge AI projects can communicate visually with the real world in a beautiful and engaging way.

We begin by setting up the NeoPixel ring using the SPI interface on the SunFounder Fusion Hat. After importing the necessary libraries (time, board, neopixel_spi, colorsys, and math), we create a simple and reusable hsv2rgb() function that converts Hue values (0.0 to 1.0) into RGB colors that the NeoPixels can understand. This function becomes the foundation for smooth rainbow effects later in the lesson.The lesson starts with basic pixel control. We manually light up each of the 12 pixels one at a time using different colors (red, green, blue, cyan, magenta, yellow, etc.). This slow, deliberate approach lets you clearly see how individual pixel addressing works and helps students understand the coordinate system of the ring.Next, we explore full-ring control by making the entire ring blink between bright red and blue. We then move into motion with a running green pixel moving across a red background — a great introduction to animation techniques. This is followed by a more advanced chasing effect where a blue pixel chases a green pixel around a dim red background.One of the highlights of this lesson is the gentle pulsating aqua effect. Using a sine wave (math.sin), we create a smooth breathing/pulsing animation where the brightness of the color rises and falls naturally. This technique produces a very professional and visually pleasing result that students can easily adapt for future projects.

Finally, we create a rainbow effect. First, we display a uniform rainbow where all 12 pixels show the same color that cycles smoothly through the entire spectrum.

We finish the lesson by assigning the homework. The homework is for you to create the classic running rainbow (what I like to call a “Runbow”), where the colors flow continuously around the ring — one of the most popular and impressive NeoPixel animations.

This lesson reinforces important programming concepts including loops, functions, color theory (HSV vs RGB), timing control, and animation techniques, while giving students an exciting visual payoff. The skills learned here open the door to creating stunning visual feedback for future AI projects — whether it’s status indicators, emotional displays, or attention-grabbing outputs from your edge AI models.

# ====================================================================
# DISCLAIMER:
# This code is provided as-is for educational and experimental 
# purposes only. The author makes no representations or warranties of 
# any kind concerning the safety, suitability, or accuracy of this 
# code. Use at your own risk. The author assumes no liability for any 
# damages, system failures, security breaches, or network issues 
# resulting from the use or implementation of this script.
# ====================================================================
 
import time
import board
import neopixel_spi as neopixel
import colorsys
import math

def hsv2rgb(h):
    r, g, b = colorsys.hsv_to_rgb(h, 1, 1)
    return (int(r*255),int(g*255),int(b*255))

spi = board.SPI()
LED_COUNT = 12
PO = neopixel.GRB
strip = neopixel.NeoPixel_SPI(spi,
        LED_COUNT,pixel_order=PO,
        auto_write = False)
strip.fill(0)
strip.show()

strip[0] = (255,0,0)
strip.show()
ts=.1
time.sleep(ts)

strip[1] = (0,255,0)
strip.show()
time.sleep(ts)

strip[2] = (0,0,255)
strip.show()
time.sleep(.1)

strip[3] = (0,255,255)
strip.show()
time.sleep(ts)

strip[4] = (255,0,255)
strip.show()
time.sleep(.1)

strip[5] = (255,255,0)
strip.show()
time.sleep(.1)

strip[6] = (255,100,0)
strip.show()
time.sleep(ts)

strip[7] = (128,0,255)
strip.show()
time.sleep(.1)

strip[8] = (0,255,128)
strip.show()
time.sleep(.1)

strip[9] = (255,0,128)
strip.show()
time.sleep(ts)

strip[10] = (128,255,0)
strip.show()
time.sleep(ts)

strip[11] = (0,128,255)
strip.show()
time.sleep(.1)
ts2=5
for i in range(5):
    strip.fill((255,0,0))
    strip.show()

    time.sleep(ts2)
    
    strip.fill((0,0,255))
    strip.show()
    time.sleep(ts2)
    
strip.fill((255,0,0))
strip.show()
ts3=1
time.sleep(ts3)
ts4=.3
for lap in range(3):
    for i in range(12):
        strip[i] = (0,255,0)
        strip.show()
        time.sleep(ts4)
        strip[i] = (255,0,0)

strip.fill((40,0,0))
strip.show()
time.sleep(ts3)

for lap in range(4):
    for i in range(12):
        greenPos = i
        bluePos = (i + 6)%12
        
        strip[greenPos] = (0,255,0)
        strip[bluePos] = (0,0,255)
        strip.show()
        time.sleep(ts4)
        
        strip[greenPos] = (40,0,0)
        strip[bluePos] = (40,0,0)
        
for laps in range(6):
    for step in range(360):
        brightness= (math.sin(step*3.1415/180)+1)/2
        r = 0
        g = int(255*brightness)
        b = int(50*brightness)
        strip.fill((r,g,b))
        strip.show()
        time.sleep(.005)
        
for laps in range(5):
    for step in range(100):
        hue = step/100
        color = hsv2rgb(hue)
        strip.fill(color)
        strip.show()
        time.sleep(ts)


strip.fill(0)
strip.show()

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# ====================================================================

# DISCLAIMER:

# This code is provided as-is for educational and experimental

# purposes only. The author makes no representations or warranties of

# any kind concerning the safety, suitability, or accuracy of this

# code. Use at your own risk. The author assumes no liability for any

# damages, system failures, security breaches, or network issues

# resulting from the use or implementation of this script.

# ====================================================================

import time

import board

import neopixel_spi as neopixel

import colorsys

import math

def hsv2rgb(h):

r, g, b = colorsys.hsv_to_rgb(h, 1, 1)

return (int(r*255),int(g*255),int(b*255))

spi = board.SPI()

LED_COUNT = 12

PO = neopixel.GRB

strip = neopixel.NeoPixel_SPI(spi,

LED_COUNT,pixel_order=PO,

auto_write = False)

strip.fill(0)

strip.show()

strip[0] = (255,0,0)

strip.show()

ts=.1

time.sleep(ts)

strip[1] = (0,255,0)

strip.show()

time.sleep(ts)

strip[2] = (0,0,255)

strip.show()

time.sleep(.1)

strip[3] = (0,255,255)

strip.show()

time.sleep(ts)

strip[4] = (255,0,255)

strip.show()

time.sleep(.1)

strip[5] = (255,255,0)

strip.show()

time.sleep(.1)

strip[6] = (255,100,0)

strip.show()

time.sleep(ts)

strip[7] = (128,0,255)

strip.show()

time.sleep(.1)

strip[8] = (0,255,128)

strip.show()

time.sleep(.1)

strip[9] = (255,0,128)

strip.show()

time.sleep(ts)

strip[10] = (128,255,0)

strip.show()

time.sleep(ts)

strip[11] = (0,128,255)

strip.show()

time.sleep(.1)

ts2=5

for i in range(5):

strip.fill((255,0,0))

strip.show()

time.sleep(ts2)

strip.fill((0,0,255))

strip.show()

time.sleep(ts2)

strip.fill((255,0,0))

strip.show()

ts3=1

time.sleep(ts3)

ts4=.3

for lap in range(3):

for i in range(12):

strip[i] = (0,255,0)

strip.show()

time.sleep(ts4)

strip[i] = (255,0,0)

strip.fill((40,0,0))

strip.show()

time.sleep(ts3)

for lap in range(4):

for i in range(12):

greenPos = i

bluePos = (i + 6)%12

strip[greenPos] = (0,255,0)

strip[bluePos] = (0,0,255)

strip.show()

time.sleep(ts4)

strip[greenPos] = (40,0,0)

strip[bluePos] = (40,0,0)

for laps in range(6):

for step in range(360):

brightness= (math.sin(step*3.1415/180)+1)/2

r = 0

g = int(255*brightness)

b = int(50*brightness)

strip.fill((r,g,b))

strip.show()

time.sleep(.005)

for laps in range(5):

for step in range(100):

hue = step/100

color = hsv2rgb(hue)

strip.fill(color)

strip.show()

time.sleep(ts)

strip.fill(0)

strip.show()

In this class we are using this as our standard components. You should already have the core circuit built and should already have the OLED connected. Today you will add the NeoPixel array.

Our core circuit is:

Last week we also added the SSD1306 OLED Display.

And finally today we add the NeoPixel ring from the Fusion AI Lab Kit.

Raspberry Pi Pico

Controlling NeoPixel Array on PIO State Machine on Raspberry Pi Pico

January 21, 2025 admin

In this video lesson we show how neopixels work at a fundamental level, and show how you can use the Raspberry Pi Pico State Machines to control the neoixels. Neopixels are an excellent example for showing the importance of the pico state machine. The neopixels demand precise timing and sequence of bits to operate properly, and that precision can not be achieved in python. The video explains how the State Machines can be programmed to control the neopixels.

For your convenience, the code is included below.

# ====================================================================
# DISCLAIMER:
# This code is provided as-is for educational and experimental 
# purposes only. The author makes no representations or warranties of 
# any kind concerning the safety, suitability, or accuracy of this 
# code. Use at your own risk. The author assumes no liability for any 
# damages, system failures, security breaches, or network issues 
# resulting from the use or implementation of this script.
# ====================================================================

import rp2
from machine import Pin
import time
@rp2.asm_pio(sideset_init=rp2.PIO.OUT_HIGH,
             out_shiftdir=rp2.PIO.SHIFT_LEFT,
             autopull=True,
             pull_thresh=24)
def ws2812():
    wrap_target()
    label("bitloop")
    out(x,1).side(0)
    jmp(not_x,"do_zero").side(1)
    nop().side(1)[5-1]
    nop().side(0)[2-1]
    jmp("bitloop").side(0)
    label("do_zero")
    nop().side(1)[2-1]
    jmp("bitloop").side(0)[6-1]
    wrap()
sm=rp2.StateMachine(0,ws2812,freq=8000000,sideset_base=Pin(0))
sm.active(1)

def write_neopixel(colors):
    for color in colors:
        grb=color[1]<<16 | color[0]<<8 | color[2]
        sm.put(grb,8)
        
    
NUM_LEDS =8
myColor=[0]*NUM_LEDS
myColor=[[100,0,0],
         [0,100,0],
         [0,0,100],
         [0,100,100],
         [100,0,100],
         [100,100,0],
         [200,100,0],
         [255,255,255]]
write_neopixel(myColor)

# ====================================================================

# DISCLAIMER:

# This code is provided as-is for educational and experimental

# purposes only. The author makes no representations or warranties of

# any kind concerning the safety, suitability, or accuracy of this

# code. Use at your own risk. The author assumes no liability for any

# damages, system failures, security breaches, or network issues

# resulting from the use or implementation of this script.

# ====================================================================

import rp2

from machine import Pin

import time

@rp2.asm_pio(sideset_init=rp2.PIO.OUT_HIGH,

out_shiftdir=rp2.PIO.SHIFT_LEFT,

autopull=True,

pull_thresh=24)

def ws2812():

wrap_target()

label("bitloop")

out(x,1).side(0)

jmp(not_x,"do_zero").side(1)

nop().side(1)[5-1]

nop().side(0)[2-1]

jmp("bitloop").side(0)

label("do_zero")

nop().side(1)[2-1]

jmp("bitloop").side(0)[6-1]

wrap()

sm=rp2.StateMachine(0,ws2812,freq=8000000,sideset_base=Pin(0))

sm.active(1)

def write_neopixel(colors):

for color in colors:

grb=color[1]<<16 | color[0]<<8 | color[2]

sm.put(grb,8)

NUM_LEDS =8

myColor=[0]*NUM_LEDS

myColor=[[100,0,0],

[0,100,0],

[0,0,100],

[0,100,100],

[100,0,100],

[100,100,0],

[200,100,0],

[255,255,255]]

write_neopixel(myColor)

MicroPython, Raspberry Pi Pico

Control NeoPixel Array With Infrared IR Remote Control on Raspberry Pi Pico in MicroPython

July 17, 2024 admin

In this lesson we show how we can control the neoPixel array using an Infrared IR Remote Control on the Raspberry Pi Pico W in micropython. The video above explains things step-by-step. For your convenience, the code is included below. Enjoy!

# ====================================================================
# DISCLAIMER:
# This code is provided as-is for educational and experimental 
# purposes only. The author makes no representations or warranties of 
# any kind concerning the safety, suitability, or accuracy of this 
# code. Use at your own risk. The author assumes no liability for any 
# damages, system failures, security breaches, or network issues 
# resulting from the use or implementation of this script.
# ====================================================================

import neopixel
from machine import Pin
import time

pixPin = 0
pixSize = 8
pix = neopixel.NeoPixel(Pin(pixPin), pixSize)

def getRGB(deg):
    m=1/60
    if deg>=0 and deg<60:
        R=1
        G=0
        B=m*deg
    if deg>=60 and deg<120:
        R=1-m*(deg-60)
        G=0
        B=1
    if deg>=120 and deg<180:
        R=0
        G=m*(deg-120)
        B=1
    if deg>=180 and deg<240:
        R=0
        G=1
        B=1-m*(deg-180)
    if deg>=240 and deg<300:
        R=m*(deg-240)
        G=1
        B=0
    if deg>=300 and deg<360:
        R=1
        G=1-m*(deg-300)
        B=0
    myColor=(int(R*255),int(G*255),int(B*255))
    return myColor

from ir_rx.print_error import print_error
from ir_rx.nec import NEC_8
import SERVO
IRdict ={69 : 'POWER', 70: 'MODE',71 : 'OFF',
         68: 'PLAY', 64 : 'BACK', 67 : 'FORWARD', 7: 'ENTER', 21: '-',
         9 : '+', 22 : 0,25 : 'LOOP', 13:'USD' ,
         12: 1, 24 : 2,94 : 3,
        8 :4, 28 : 5, 90 : 6,
        66 : 7, 82 : 8, 74 : 9}

newCommand=[]
beginRecord=False
cmdReady=False
angleString=''
newBit=""
irPin=17
cmd=0
myIR = Pin(irPin, Pin.IN)
def callback(IRbit, addr, ctrl):
    global newCommand
    global beginRecord
    global cmdReady
    global IRdict
    global cmd
    if IRbit==69:
        beginRecord=True
        newCommand=[]
        cmdReady=False
    if beginRecord==True and IRbit!=-1:
        newCommand.append(IRdict[IRbit])
    if IRbit==7:
        cmdReady=True
        cmd=newCommand[1]
        
IR = NEC_8(myIR, callback)  # Instantiate receiver
try:
    while True:
        if cmd==0:
            for i in range(0,8):
                pix[i]=[0,0,0]
            pix.write()
        if cmd==1:
            pix.fill([255,0,0])
            pix.write()
        if cmd==2:
            pix.fill([0,255,0])
            pix.write()
        if cmd==3:
            pix.fill([0,0,255])
            pix.write() 
        if cmd==4:
            for i in range(0,360,1):
                for j in range(0,8,1):
                    deg=i+(j)*45
                    if deg>=360:
                        deg=deg-360
                    color=getRGB(deg)
                    pix[j]=color
                    if cmd!=4:
                        break
                if cmd!=4:
                    break
                pix.write()
                ts=.01
                time.sleep(ts)
        if cmd==5:
            for i in range(0,360,1):
                color=getRGB(i)
                pix.fill(color)
                pix.write()
                time.sleep(.01)
                if cmd!=5:
                    break
        if cmd==6:
            for i in range(1,8,1):
                pix.fill([255,0,0])
                pix[i]=[0,0,255]
                #pix[7-i]=green
                pix.write()
                ts=.1
                time.sleep(ts)
                if cmd!=6:
                    break
            for i in range(6,-1,-1):
                pix.fill([255,0,0])
                pix[i]=[0,0,255]
                #pix[7-i]=green
                pix.write()
                ts=.1
                time.sleep(ts)
                if cmd!=6:
                    break

except KeyboardInterrupt:
    IR.close()
    for i in range(0,8):
        pix[i]=[0,0,0]
        pix.write()
    print("Program Terminated")

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# ====================================================================

# DISCLAIMER:

# This code is provided as-is for educational and experimental

# purposes only. The author makes no representations or warranties of

# any kind concerning the safety, suitability, or accuracy of this

# code. Use at your own risk. The author assumes no liability for any

# damages, system failures, security breaches, or network issues

# resulting from the use or implementation of this script.

# ====================================================================

import neopixel

from machine import Pin

import time

pixPin = 0

pixSize = 8

pix = neopixel.NeoPixel(Pin(pixPin), pixSize)

def getRGB(deg):

m=1/60

if deg>=0 and deg<60:

R=1

G=0

B=m*deg

if deg>=60 and deg<120:

R=1-m*(deg-60)

G=0

B=1

if deg>=120 and deg<180:

R=0

G=m*(deg-120)

B=1

if deg>=180 and deg<240:

R=0

G=1

B=1-m*(deg-180)

if deg>=240 and deg<300:

R=m*(deg-240)

G=1

B=0

if deg>=300 and deg<360:

R=1

G=1-m*(deg-300)

B=0

myColor=(int(R*255),int(G*255),int(B*255))

return myColor

from ir_rx.print_error import print_error

from ir_rx.nec import NEC_8

import SERVO

IRdict ={69 : 'POWER', 70: 'MODE',71 : 'OFF',

68: 'PLAY', 64 : 'BACK', 67 : 'FORWARD', 7: 'ENTER', 21: '-',

9 : '+', 22 : 0,25 : 'LOOP', 13:'USD' ,

12: 1, 24 : 2,94 : 3,

8 :4, 28 : 5, 90 : 6,

66 : 7, 82 : 8, 74 : 9}

newCommand=[]

beginRecord=False

cmdReady=False

angleString=''

newBit=""

irPin=17

cmd=0

myIR = Pin(irPin, Pin.IN)

def callback(IRbit, addr, ctrl):

global newCommand

global beginRecord

global cmdReady

global IRdict

global cmd

if IRbit==69:

beginRecord=True

newCommand=[]

cmdReady=False

if beginRecord==True and IRbit!=-1:

newCommand.append(IRdict[IRbit])

if IRbit==7:

cmdReady=True

cmd=newCommand[1]

IR = NEC_8(myIR, callback) # Instantiate receiver

try:

while True:

if cmd==0:

for i in range(0,8):

pix[i]=[0,0,0]

pix.write()

if cmd==1:

pix.fill([255,0,0])

pix.write()

if cmd==2:

pix.fill([0,255,0])

pix.write()

if cmd==3:

pix.fill([0,0,255])

pix.write()

if cmd==4:

for i in range(0,360,1):

for j in range(0,8,1):

deg=i+(j)*45

if deg>=360:

deg=deg-360

color=getRGB(deg)

pix[j]=color

if cmd!=4:

break

if cmd!=4:

break

pix.write()

ts=.01

time.sleep(ts)

if cmd==5:

for i in range(0,360,1):

color=getRGB(i)

pix.fill(color)

pix.write()

time.sleep(.01)

if cmd!=5:

break

if cmd==6:

for i in range(1,8,1):

pix.fill([255,0,0])

pix[i]=[0,0,255]

#pix[7-i]=green

pix.write()

ts=.1

time.sleep(ts)

if cmd!=6:

break

for i in range(6,-1,-1):

pix.fill([255,0,0])

pix[i]=[0,0,255]

#pix[7-i]=green

pix.write()

ts=.1

time.sleep(ts)

if cmd!=6:

break

except KeyboardInterrupt:

IR.close()

for i in range(0,8):

pix[i]=[0,0,0]

pix.write()

print("Program Terminated")

Technology Tutorials

Tag Archives: neoPixel

AI on the Edge LESSON 47: Emotion Detector Using MediaPipe, OpenCV and Raspberry Pi

AI on the Edge LESSON 45: Adding a NeoPixel Ring To Your Raspberry Pi Project

Controlling NeoPixel Array on PIO State Machine on Raspberry Pi Pico

Control NeoPixel Array With Infrared IR Remote Control on Raspberry Pi Pico in MicroPython

Making The World a Better Place One High Tech Project at a Time. Enjoy!