board/time/time.c
/** Returns the number of microseconds since the Arduino board began running the current program. This number will overflow (go back to zero), after approximately 70 minutes. */
Returns the number of microseconds since the Arduino board began running the current program. This number will overflow (go back to zero), after approximately 70 minutes.
Returns the number of microseconds since the Arduino board began running the current program . This number will overflow ( go back to zero ) after approximately 70 minutes .
unsigned long micros(void) {
	unsigned long m;
	unsigned char oldSREG = SREG, t;
	cli();
	m = timer0_overflow_count;
	t = TCNT0;
	if((TIFR0 & (1 << TOV0)) && (t < 255)) {
		m++;
	}
	SREG = oldSREG;
	return ((m << 8) + t) * (64 / clockCyclesPerMicrosecond());
}
unsigned long micros ( void ) { unsigned long m ; unsigned char oldSREG = SREG , t ; cli ( ) ; m = timer0_overflow_count ; t = TCNT0 ; if ( ( TIFR0 & ( 1 << TOV0 ) ) && ( t < 255 ) ) { m ++ ; } SREG = oldSREG ; return ( ( m << 8 ) + t ) * ( 64 / clockCyclesPerMicrosecond ( ) ) ; }
Returns the number of microseconds since the Arduino board began running the current program.
Returns the number of microseconds since the Arduino board began running the current program .