keypad_test2.ino

#include "Adafruit_NeoTrellisM4.h"

// The NeoTrellisM4 object is a keypad and neopixel strip subclass
// that does things like auto-update the NeoPixels and stuff!
Adafruit_NeoTrellisM4 trellis = Adafruit_NeoTrellisM4();

boolean *lit_keys;

void setup(){
  Serial.begin(115200);
    
  trellis.begin();
  trellis.setBrightness(80);

  Serial.println("toggle keypad test!");

  lit_keys = new boolean[trellis.num_keys()];
  
  for (int i=0; i<trellis.num_keys(); i++) {
    lit_keys[i] = false;
  }
}
  
void loop() {
  // put your main code here, to run repeatedly:
  trellis.tick();

  while (trellis.available()){
    keypadEvent e = trellis.read();
    
    if (e.bit.EVENT == KEY_JUST_PRESSED) {
      int key = e.bit.KEY;  // shorthand for what was pressed
      Serial.print(key); Serial.println(" pressed");
      lit_keys[key] = !lit_keys[key];
      if (lit_keys[key]) {
        trellis.setPixelColor(key, Wheel(random(255)));
      } else {
        trellis.setPixelColor(key, 0);
      }      
    }
  }
  
  delay(10);
}


// Input a value 0 to 255 to get a color value.
// The colours are a transition r - g - b - back to r.
uint32_t Wheel(byte WheelPos) {
  WheelPos = 255 - WheelPos;
  if(WheelPos < 85) {
    return trellis.Color(255 - WheelPos * 3, 0, WheelPos * 3);
  }
  if(WheelPos < 170) {
    WheelPos -= 85;
    return trellis.Color(0, WheelPos * 3, 255 - WheelPos * 3);
  }
  WheelPos -= 170;
  return trellis.Color(WheelPos * 3, 255 - WheelPos * 3, 0);
}