basic implementation of analog inputs and test script

examples/calibrate_analog/calibrate_analog.ino

@@ -0,0 +1,70 @@
+#include "gravity.h"
+
+byte idx = 0;
+bool reversed = false;
+bool freeze = false;
+byte selected_param = 0;
+
+// Initialize the gravity library and attach your handlers in the setup method.
+void setup() {
+    // Initialize Gravity.
+    gravity.Init();
+
+    // Attach handlers.
+    gravity.clock.AttachIntHandler(IntClock);
+}
+
+// The loop method must always call `gravity.Process()` to read any peripherial state changes.
+void loop() {
+    gravity.Process();
+
+    UpdateDisplay();
+}
+
+// The rest of the code is your apps logic!
+
+void IntClock(uint32_t tick) {
+    if (tick % 12 == 0  && ! freeze) {
+        gravity.outputs[idx].Low();
+        if (reversed) {
+            idx = (idx == 0) ? OUTPUT_COUNT - 1 : idx - 1;
+        } else {
+            idx = (idx + 1) % OUTPUT_COUNT;
+        }
+        gravity.outputs[idx].High();
+    }
+}
+
+
+void UpdateDisplay() {
+    gravity.display.clearDisplay();
+
+    int cv1 = gravity.cv1.Read();
+    int cv2 = gravity.cv2.Read();
+    
+    gravity.display.setCursor(10, 10);
+    gravity.display.print(F("CV1: "));
+    gravity.display.print(cv1);
+
+    gravity.display.drawRect(10, 22, 100, 10, 1);
+    if (cv1 >= 512) {
+        int x = (float(cv1 - 512) / 512.0) * 50; 
+        gravity.display.fillRect(60, 22, x, 10, 1);
+    } else {
+        int x = (float(512 - cv1) / 512.0) * 50; 
+        gravity.display.fillRect(60-x, 22, x, 10, 1);
+    }
+
+    gravity.display.setCursor(10, 42);
+    gravity.display.print(F("CV2: "));
+    gravity.display.print(cv2);
+    if (cv2 >= 512) {
+        int x = (float(cv2 - 512) / 512.0) * 50; 
+        gravity.display.fillRect(60, 42, x, 10, 1);
+    } else {
+        int x = (float(512 - cv2) / 512.0) * 50; 
+        gravity.display.fillRect(60-x, 42, x, 10, 1);
+    }
+
+    gravity.display.display();
+}