First init.

libraries/Adafruit_seesaw_Library/examples/NeoKey_1x4/basic_multikey/basic_multikey.ino

@@ -0,0 +1,92 @@
+#include "Adafruit_NeoKey_1x4.h"
+#include "seesaw_neopixel.h"
+
+#define Y_DIM 2 //number of rows of keys
+#define X_DIM 4 //number of columns of keys
+
+// create a matrix of NeoKey 1x4's 
+// this example is just two, one on top of another to make a 2x4 grid
+Adafruit_NeoKey_1x4 nk_array[Y_DIM][X_DIM/4] = {
+  { Adafruit_NeoKey_1x4(0x30) }, 
+  { Adafruit_NeoKey_1x4(0x31) },
+};
+
+// pass this matrix to the multi-neokey object
+Adafruit_MultiNeoKey1x4 neokey((Adafruit_NeoKey_1x4 *)nk_array, Y_DIM, X_DIM/4);
+
+
+void setup() {
+  Serial.begin(115200);
+  while (! Serial) delay(10);
+   
+  if (! neokey.begin()) {  // start matrix
+    Serial.println("Could not start NeoKeys, check wiring?");
+    while(1) delay(10);
+  }
+  
+  Serial.println("NeoKey started!");
+
+  // Pulse all the LEDs on to show we're working
+  for (uint16_t i=0; i< X_DIM*Y_DIM; i++) {
+    neokey.setPixelColor(i, 0x808080); // make each LED white
+    neokey.show();
+    delay(50);
+  }
+  for (uint16_t i=0; i< X_DIM*Y_DIM; i++) {
+    neokey.setPixelColor(i, 0x000000);
+    neokey.show();
+    delay(50);
+  }
+
+  // activate all keys and set callbacks
+  for(int y=0; y<Y_DIM; y++){
+    for(int x=0; x<X_DIM; x++){
+      neokey.registerCallback(x, y, blink);
+    }
+  }
+}
+
+void loop() {
+  neokey.read();
+
+  delay(10);    // don't print too fast
+}
+
+
+//define a callback for key presses
+NeoKey1x4Callback blink(keyEvent evt) {
+  uint8_t key = evt.bit.NUM;
+  
+  if (evt.bit.EDGE == SEESAW_KEYPAD_EDGE_RISING) {
+    Serial.print("Key press ");
+    Serial.println(key);
+    neokey.setPixelColor(key, Wheel(map(key, 0, X_DIM*Y_DIM, 0, 255)));
+    
+  } else if (evt.bit.EDGE == SEESAW_KEYPAD_EDGE_FALLING) {
+    Serial.print("Key release ");
+    Serial.println(key);
+
+    neokey.setPixelColor(key, 0);
+  }
+
+  // Turn on/off the neopixels!
+  neokey.show();
+  return 0;
+}
+
+/******************************************/
+
+// Input a value 0 to 255 to get a color value.
+// The colors are a transition r - g - b - back to r.
+uint32_t Wheel(byte WheelPos) {
+  if(WheelPos < 85) {
+   return seesaw_NeoPixel::Color(WheelPos * 3, 255 - WheelPos * 3, 0);
+  } else if(WheelPos < 170) {
+   WheelPos -= 85;
+   return seesaw_NeoPixel::Color(255 - WheelPos * 3, 0, WheelPos * 3);
+  } else {
+   WheelPos -= 170;
+   return seesaw_NeoPixel::Color(0, WheelPos * 3, 255 - WheelPos * 3);
+  }
+  return 0;
+}