simple test, fully working 'Sporttafel'

.gitignore

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+.pio

platformio.ini

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+[env:ws2812b]
+platform = espressif32
+board = esp32dev
+framework = arduino
+lib_deps = https://github.com/adafruit/Adafruit_NeoPixel
+upload_port = /dev/ttyUSB0
+upload_speed = 460800
+monitor_speed = 115200

src/main.cpp

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+#include <Adafruit_NeoPixel.h>
+
+#define countof(a)  (sizeof(a) / sizeof((a)[0]))
+
+#define ___         0
+#define TTT         85
+#define HHH         127
+#define XXX         255
+
+#define GPIO        26
+#define PIXELS      (4 * 7 * 6 + 4 * 4)
+#define BRIGHTNESS  32
+
+Adafruit_NeoPixel pixels(PIXELS, GPIO, NEO_GRB + NEO_KHZ800);
+
+struct color {
+  uint8_t r, g, b;
+};
+
+color colors[] = {
+    {XXX, ___, ___},
+    {HHH, HHH, ___},
+    {___, XXX, ___},
+    {___, HHH, HHH},
+    {___, ___, XXX},
+    {HHH, ___, HHH},
+    {TTT, TTT, TTT},
+};
+
+color *c = colors;
+
+int step = 0;
+
+int dir = 1;
+
+void setup() {
+  delay(500);
+  Serial.begin(115200);
+  Serial.println("\n\n\nstartup");
+  pixels.begin();
+  pixels.setBrightness(BRIGHTNESS);
+  pixels.clear();
+}
+
+void loop() {
+  pixels.setPixelColor(step, c->r, c->g, c->b);
+  pixels.show();
+
+  step += dir;
+  if (step < 0 || step > PIXELS - 1) {
+    dir = -dir;
+    c = (c + 1 - colors) % countof(colors) + colors;
+  }
+}