#include<SoftwareSerial.h>

int rxPin = 3;
int txPin = 4;
char chr = 'a';
int ms = 20000;
SoftwareSerial myserial(rxPin, txPin);
void setup()
{
  pinMode(0, OUTPUT);
  myserial.begin(9600);
}

void loop()
{
  while(myserial.available()){
  char chr = myserial.read();
  //myserial.println(chr);
  for (int j = 0; j < 30; ++j)
  {
    if (chr == (j + 97))
    {
      for (int i = 0; i < 10; ++i) {
        digitalWrite(0, HIGH);
        delayMicroseconds(1000 + (j * 100));
        digitalWrite(0, LOW);
        delayMicroseconds(ms - (1000 + (j * 100)));
      }
    }
  }
  delay(10);
}
}