Merge pull request Arduino-IRremote#198 from pcoughlin/master

update custom_delay function

Author: z3t0

IRremote.h

@@ -253,7 +253,7 @@ class IRsend
 public:
 IRsend () { }
 
-void custom_delay_ms (unsigned int time);
+void custom_delay_usec (unsigned long uSecs);
 void enableIROut	(int khz) ;
 void mark	(int usec) ;
 void space	(int usec) ;

irSend.cpp

@@ -22,7 +22,7 @@ void IRsend::sendRaw (unsigned int buf[], unsigned char len, unsigned char hz
 void IRsend::mark (int time)
 {
 TIMER_ENABLE_PWM; // Enable pin 3 PWM output
-if (time > 0) custom_delay_ms(time);
+if (time > 0) custom_delay_usec(time);
 }
 
 //+=============================================================================
@@ -33,7 +33,7 @@ void IRsend::mark (int time)
 void IRsend::space (int time)
 {
 TIMER_DISABLE_PWM; // Disable pin 3 PWM output
-if (time > 0) IRsend::custom_delay_ms(time);
+if (time > 0) IRsend::custom_delay_usec(time);
 }
 
 
@@ -71,14 +71,16 @@ void IRsend::enableIROut (int khz)
 //+=============================================================================
 // Custom delay function that circumvents Arduino's delayMicroseconds limit
 
-void IRsend::custom_delay_ms(unsigned int time) {
-if (time)
-{
-if (time > 16000)
-{
-delayMicroseconds(time % 1000);
-delay(time / 1000);
-} 
-else delayMicroseconds(time);
-}
+void IRsend::custom_delay_usec(unsigned long uSecs) {
+ if (uSecs > 4) {
+ unsigned long start = micros();
+ unsigned long endMicros = start + uSecs - 4;
+ if (endMicros < start) { // Check if overflow
+ while ( micros() > start ) {} // wait until overflow
+ }
+ while ( micros() < endMicros ) {} // normal wait
+ } else {
+ __asm__("nop\n\t"); // must have or compiler optimizes out
+ }
 }
+