Merge pull request arduino#149 from GMagician/fix-compile-warnings

Fix compile warnings

Author: hathach

cores/arduino/Adafruit_TinyUSB_Core/Adafruit_TinyUSB_Core.cpp

@@ -105,7 +105,7 @@ uint8_t load_serial_number(uint16_t* serial_str)
 
   static const char nibble_to_hex[16] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
 
-  for (int i = 0; i < sizeof(raw_id); i++) {
+  for (unsigned int i = 0; i < sizeof(raw_id); i++) {
     for (int j = 0; j < 2; j++) {
       uint8_t nibble = (raw_id[i] >> (j * 4)) & 0xf;
       // Strings are UTF-16-LE encoded.

cores/arduino/pulse.c

@@ -44,7 +44,7 @@ uint32_t pulseIn(uint32_t pin, uint32_t state, uint32_t timeout)
   volatile uint32_t *port = &(PORT->Group[p.ulPort].IN.reg);
   uint32_t usCallStart;  // microseconds at start of call, for timeout.
   uint32_t usPulseStart; // microseconds at start of measured pulse.
-  usCallStart = micros();
+  usCallStart = usPulseStart = micros();
   // wait for any previous pulse to end
   while ((*port & bit) == stateMask) {
       if (micros() - usCallStart > timeout)