first commit DMX NeoPixel code

Author: John Park

DMX_NeoPixels/.uno.platform.only

@@ -0,0 +1,103 @@
+// SPDX-FileCopyrightText: 2024 John Park for Adafruit Industries
+//
+// SPDX-License-Identifier: MIT
+
+// Use a DMX controller to drive NeoPixel strips
+// Arduino Uno or Metro 328 + Conceptinetics DMX Shield
+// Recieves incoming DMX messages from controller, translates to NeoPixel
+
+
+#include <Conceptinetics.h>
+#include <Adafruit_NeoPixel.h>
+
+// User adjust these for the number of strips, pins, pixels per strip, and color formats:
+#define NUM_STRIPS 3
+const int pin_for_strip[] = {A0, A1, A2};
+const int leds_per_strip[] = {30, 20, 30};
+const neoPixelType format_per_strip[] = {NEO_GRB + NEO_KHZ800, NEO_BGR + NEO_KHZ800, NEO_GRB + NEO_KHZ800 };
+
+#define CH_PER_STRIP 16  // only 4 used per strip, but 16 is nicer on UI of controllers that have 16 channel/page
+#define DMX_CHANNELS   (CH_PER_STRIP * NUM_STRIPS) 
+
+const int ledPin = 13;
+
+Adafruit_NeoPixel *strips[NUM_STRIPS];
+
+DMX_Slave dmx_slave ( DMX_CHANNELS ); // Configure a DMX receiving controller
+uint16_t channelValues[DMX_CHANNELS];  // Array to store DMX values
+
+
+void setup() {      
+  // Set led pin as output pin
+    pinMode ( ledPin, OUTPUT );
+    digitalWrite(ledPin, HIGH);
+
+  // set up strips
+  for(int i=0; i< NUM_STRIPS; i++) {  
+    int pin = pin_for_strip[i];
+    int num_leds  =  leds_per_strip[i];
+    int format = format_per_strip[i];
+    Adafruit_NeoPixel *strip = new Adafruit_NeoPixel(num_leds, pin, format);
+    strips[i] = strip;
+    strips[i]->begin();
+  }       
+    // light up all the strips RGB to test
+  for(int i=0; i< NUM_STRIPS; i++) { 
+    strips[i]->fill(0xff0000);
+    strips[i]->show();
+    delay(1000);
+    strips[i]->fill(0x00ff00);
+    strips[i]->show();
+    delay(1000);
+    strips[i]->fill(0x0000ff);
+    strips[i]->show();
+  }
+  delay(1000);
+
+  // Enable DMX receiving interface and start receiving DMX data
+  dmx_slave.enable ();  
+  dmx_slave.setStartAddress (1);
+}
+
+
+void loop() 
+{
+  // Fetch all DMX channel values into the array
+  for (int i = 0; i < DMX_CHANNELS; i++) {
+      channelValues[i] = dmx_slave.getChannelValue(i + 1);  // Get values starting from channel 1
+  }
+
+  for(int i=0; i<NUM_STRIPS; i++){
+    //remap some channels for specific value ranges
+    uint16_t strip_hue1 = map(channelValues[0 + (i * CH_PER_STRIP)], 0, 255, 0, 65535);
+    uint16_t strip_hue2 = map(channelValues[4 + (i * CH_PER_STRIP)], 0, 255, 0, 65535);
+    uint16_t strip_pix1 = map(channelValues[3 + (i * CH_PER_STRIP)], 0, 255, 0, leds_per_strip[i] - 1);
+    uint16_t strip_pix2 = map(channelValues[7 + (i * CH_PER_STRIP)], 0, 255, 0, leds_per_strip[i] - 1);
+
+    strips[i]->fill(0x000000);
+    strips[i]->setPixelColor(strip_pix1, strips[i]->ColorHSV(strip_hue1, channelValues[1+(i*CH_PER_STRIP)], channelValues[2+(i*CH_PER_STRIP)]));  //first pixel
+    strips[i]->setPixelColor(strip_pix2, strips[i]->ColorHSV(strip_hue2, channelValues[5+(i*CH_PER_STRIP)], channelValues[6+(i*CH_PER_STRIP)]));  //last pixel
+    // all the pixels in between
+    for (int j = strip_pix1; j <= strip_pix2; j++) {  
+      float fraction = float(j - strip_pix1) / float(strip_pix2 - strip_pix1); // Calculate the fraction of the interpolation (0 to 1)
+      // Interpolate HSV components (Hue, Saturation, Value)
+      uint16_t interpolated_hue = int(lerp(strip_hue1, strip_hue2, fraction)) % 65536;  // Wrap around Hue
+      uint16_t interpolated_saturation = lerp(channelValues[1+(i*CH_PER_STRIP)], channelValues[5+(i*CH_PER_STRIP)], fraction);
+      uint16_t interpolated_value = lerp(channelValues[2+(i*CH_PER_STRIP)], channelValues[6+(i*CH_PER_STRIP)], fraction);
+
+    // Set the interpolated color to the pixel
+      strips[i]->setPixelColor(j, strips[i]->ColorHSV(interpolated_hue, interpolated_saturation, interpolated_value));
+    }
+  }
+
+  for(int i=0; i<NUM_STRIPS; i++){
+    strips[i]->show();
+  }
+
+  delay(100);
+}
+
+// Linear interpolation function
+float lerp(float start, float end, float t) {
+  return start + (end - start) * t;
+}