Simple grundfos home heating system pump status indicator

//sketch to use digispark as simple grundfos pump status indicator
#define in 0 //pin for pwm input from pump
int duty;float on, off ,period;
void setup() {
pinMode(in,INPUT);
pinMode(1,OUTPUT); //just using like vcc pin for rgb led strip
pinMode(2,OUTPUT); //output for led
pinMode(3,OUTPUT); //output for led
pinMode(4,OUTPUT); //output for led
digitalWrite(1,1);// power for rgb
digitalWrite(2,1); //turning off led
digitalWrite(3,1); //turning off led
digitalWrite(4,1);}//turning off led
void loop() {
on = pulseIn(in,HIGH);
off = pulseIn(in,LOW);
period = on+off;
duty = (on/period)*100;
if(duty == 0)digitalWrite(4,0);else digitalWrite(4,1);           //it means that pump is turned off turning on indication led in my case blue
if(duty>0 && duty<71)digitalWrite(2,0);else digitalWrite(2,1);   //it means that pump is working normaly turning on other led in my case green
if(duty>70 && duty<100)                                          //this is frequency range for errors i just use 1 led to cover all errors in my case red
{digitalWrite(3,0);
delay(70);
digitalWrite(3,1);                                               //little strobe effect for easier notice that something is wrong and needed to see pumps status pannel
delay(70);
digitalWrite(3,0);
delay(70);
digitalWrite(3,1);
delay(70);
digitalWrite(3,0);
delay(70);
digitalWrite(3,1);
delay(70);
digitalWrite(3,0);}
else digitalWrite(3,1);
delay(1000);}