LED Heartbeat

Forum 2005-2010 (read only) General Exhibition
1

Silly little first expirement.
But it works nicely...and I maaaay have even gotten the math right.

//Heartbeat LED
//elCalvoMike 12-6-2008
#define LED 11 //analog pin location for ArduinoMini - change for other boards
int i = 0;
int pmw = 255; //set PWM max - this can differ for other board pins
int rate = 25; //this is the beats per minute (60000 ms)
//because there are two beats to simulate the 'lub-dub' of the heart,
// a 60 beat heart rate is only a value of 30 in the rate variable
//the delay is the key to this programs realism - divide the rate into a minute, then weight it and divide by the pmw
//you can modify the weight by changing the fractions (i.e .1, .2, .6) but to keep the timing correct, they should total 1
//.1+.2+.1+.6 = 1

void setup() {
pinMode(LED, OUTPUT);
}

void loop(){
for(i = 0; i < pmw; i++) {
analogWrite(LED,i);
delay(((60000/rate)*.1)/pmw);
}

for (i = pmw; i > 0; i--){
analogWrite(LED,i);
delay(((60000/rate)*.2)/pmw);
}

for(i = 0; i < pmw; i++) {
analogWrite(LED,i);
delay(((60000/rate)*.1)/pmw);
}

for (i = pmw; i > 0; i--){
analogWrite(LED,i);
delay(((60000/rate)*.6)/pmw);
}

}

2

This would be awesome if you tied it in with a Polar HRM