//clignoteut 50%
double tt0,t0;//pour la temporisation
int b=0,out=13;


void setup() {
  // put your setup code here, to run once:
pinMode(out, OUTPUT);
pinMode(12, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
if(!tt0) t0=micros(),b=!b;
tt0=micros()-t0<1000000;//period 2000ms
digitalWrite(12,micros()-t0<100000);//pulse 100 ms
digitalWrite(out,b);//clignote 50%
}