commit f248c6205af56941cc0d5a893b6be4a4c161ee76
Author: Dennis Gunia <mail@denniagunia.de>
Date:   Sat May 28 20:12:01 2022 +0200

    initial

diff --git a/song_pedal.ino b/song_pedal.ino
new file mode 100644
index 0000000..c586f61
--- /dev/null
+++ b/song_pedal.ino
@@ -0,0 +1,92 @@
+/**
+ * Dennis Gunia (c) 2022
+ *
+ * USB Keyboard for Worship song-switching
+ * 
+ *
+ * Designed for Arduino Pro Micro
+ * 
+ * Use pin 8 and 9 as inputs. Connect Switches to Ground.
+ * 
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * or in the "license" file accompanying this file. This file is distributed
+ * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+
+
+#include <Keyboard.h>
+
+#define SW_1_PIN 8
+#define SW_2_PIN 9
+
+#define debounceTimeConst 200   //debounce time in ms
+
+unsigned long sw1_debounce = 0; //debounce var (last time button was pressed)
+unsigned long sw2_debounce = 0; //debounce var (last time button was pressed)
+
+void setup() {
+  // Set input pins with pullup
+  pinMode(SW_1_PIN, INPUT_PULLUP);
+  pinMode(SW_2_PIN, INPUT_PULLUP);
+
+  //Initialize USB Keyboard
+  Keyboard.begin();
+}
+
+void loop() {
+  unsigned long now = millis();           //timestamp of start of loop
+  // debounce button 1
+  if(digitalRead(SW_1_PIN) == false){
+    if(sw1_debounce + debounceTimeConst < now){
+      unsigned long pressed = millis();   //store time when button is pressed
+      delay(150);                         //initial delay to compensate bounce
+      while( digitalRead(SW_1_PIN) == false ){
+        // wait for button release
+      }
+      if (pressed + 1000 > millis() ) {
+        // pressed shorter than 1s
+        pdf_up();
+      }else{
+        // pressed longer than 1s
+        pdf_top();
+      }
+    }
+    sw1_debounce = now;    
+  }
+
+  // debounce button 2
+  if(digitalRead(SW_2_PIN) == false){
+    if(sw2_debounce + debounceTimeConst < now){ pdf_down(); }
+    sw2_debounce = now;
+  }
+  //Serial.println(sw1_debounce);
+}
+
+//Keyborad Event definitions
+
+void pdf_up() {
+    Keyboard.press(KEY_PAGE_UP);  
+    //Keyboard.press(KEY_LEFT_ARROW);  
+    delay(100);
+    Keyboard.releaseAll();
+}
+
+void pdf_down() {
+    Keyboard.press(KEY_PAGE_DOWN);  
+    //Keyboard.press(KEY_RIGHT_ARROW);  
+    delay(100);
+    Keyboard.releaseAll();
+}
+
+void pdf_top() {
+    Keyboard.press(KEY_RIGHT_GUI);  
+    Keyboard.press(KEY_UP_ARROW);  
+    delay(100);
+    Keyboard.releaseAll();
+}