InterruptIn.h: Update comments

Author: Naveen Kaje

drivers/InterruptIn.h

@@ -48,6 +48,7 @@ namespace mbed {
  * }
  *
  * int main() {
+ *     // register trigger() to be called upon the rising edge of event
  *     event.rise(&trigger);
  *     while(1) {
  *         led = !led;
@@ -71,7 +72,10 @@ class InterruptIn : private NonCopyable<InterruptIn> {
      *  and the pin configured to the specified mode.
      *
      *  @param pin InterruptIn pin to connect to
-     *  @param mode The mode to set the pin to (PullUp/PullDown/etc.)
+     *  @param mode Desired Pin mode configuration.
+     *  (Valid values could be PullNone/PullDown/PullUp/PullDefault
+     *  See PinNames.h for your target for definitions)
+     *
      */
     InterruptIn(PinName pin, PinMode mode);
 
@@ -142,7 +146,8 @@ class InterruptIn : private NonCopyable<InterruptIn> {
 
     /** Set the input pin mode
      *
-     *  @param pull PullUp, PullDown, PullNone
+     *  @param pull PullUp, PullDown, PullNone, PullDefault
+     *  See PinNames.h for your target for definitions)
      */
     void mode(PinMode pull);