int poten = A0; 
int led1 = 2;
int led2 = 3;
int interval1 = 1000;
int interval2 = 1000;
boolean state1 = false;
boolean state2 = false;
unsigned long tp1, tc1;
unsigned long tp2, tc2;
void setup() {
  Serial.begin(9600);
  pinMode(poten, INPUT);
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  tp1 = millis();
  tp2 = millis();
}
void loop() {
  tc1 = millis();
  tc2 = millis();
  interval1 = map(analogRead(poten),1,1023,-1500,-500)*-1;
  interval2 = map(analogRead(poten),1,1023,500,1500);
  if (tc1 - tp1 >= interval1){
    tp1 = tc1;
    state1 = !state1;
    digitalWrite(led1, state1);
  }
  if (tc2 - tp2 >= interval2){
    tp2 = tc2;
    state2 = !state2;
    digitalWrite(led2, state2);
  }
}