#define led1 A1
#define led2 A2

int d1 = 300;
int d2 = 500;

uint32_t m1 = 0, m2 = 0;
void setup() {
  // put your setup code here, to run once:
  Serial.begin(57600);
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  Serial.println("Booting");

}

void checkSerial()
{
  if (Serial.available())
  {
    uint8_t c = Serial.read();
    if (c == 'A') d1 += 10;
    if (c == 'a') d1 -= 10;

  }
}


void loop() {
  // put your main code here, to run repeatedly:

  checkSerial();

  if (millis() - m1 > d1)
  {
    digitalWrite(led1, !digitalRead(led1));
    m1 = millis();
  }

  if (millis() - m2 > d2)
  {
    digitalWrite(led2, !digitalRead(led2));
    m2 = millis();
  }


}