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//
// propeller-clock.pde
//
// A propeller clock.
void setup()
{
// set up an interrupt handler on pin 2 to nitice fan pulses
attachInterrupt( 0, fanPulseHandler, RISING );
digitalWrite( 2, HIGH );
// set up output pins (4 to 13) for the led array
for( int a = 4; a < 14; a++ )
pinMode( a, OUTPUT );
// serial comms
Serial.begin( 9600 );
}
// when non-zero, the time (in microseconds) of a new fan pulse that has just
// occurred, which means that segment drawing needs to be restarted
static unsigned long new_pulse_at = 0;
// interrupt handler to count the number of fan pulses
void fanPulseHandler()
{
// ignore every other pulse
static bool ignore = true;
ignore = !ignore;
if( !ignore )
{
// set a new pulse time
new_pulse_at = micros();
}
}
// wait until it is time to draw the next segment or a new pulse has occurred
void endOfSegmentDelay()
{
while( micros() < next_segment_at && !new_pulse_at );
}
void loop()
{
static int led = 4;
unsigned long loop_start_time = micros();
// wait till it's time to draw the next segment
}
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