Simon Monk SOS example Programming Arduino Book timing error question

i have been re-writing monk's examples learn arduino syntax. when uploaded 1 sketch_05_02 did not give smooth sos in morse. added 200msec pause @ beginning of execution of flash (int duration) function. works, can't figure out why. in understaning flow of sketch appreciated.

this his.

code: [select]



// sketch 05-02
int ledpin = 13;

int durations[] = {200, 200, 200, 500, 500, 500, 200, 200, 200};

void setup()
{
  pinmode(ledpin, output);
}

void loop()
{
  (int = 0; < 9; i++)
  {
    flash(durations[i]);
  }
  delay(1000);
}

void flash(int duration)
{
   digitalwrite(ledpin, high);
   delay(duration);
   digitalwrite(ledpin, low);
   delay(duration);
}



here mine. added delay(duration) , spaced delay between loop bit longer make easier evaluate result.

code: [select]


//this sketch uses array flash sos
//simon sketch has problems - timing off - needs 200msec delay @ beginning of last block
//i found trial , error don't know why
int ledpin = 13;

int durations[] = {200, 200, 200, 500, 500, 500, 200, 200, 200};

void setup()
{
  pinmode(ledpin, output);
}

void loop()
{
  (int = 0; < 9; i++)
  {
    flash(durations[i]); //create function point positions 0-9 in durations array data
  }
  delay(2000);
}

void flash(int duration) //call flash function , give data in durations array local variable  named duration
{
  delay(duration);
  digitalwrite(ledpin, high);
  delay(duration);
  digitalwrite(ledpin, low);
  delay(duration);
}


according wikipedia article on morse code:
a 'dash' should 3 times length of 'dot'.
the time between dots or dashes in letter should same time dot.
the time between letters should 3 dot times.

i suspect changes got closer standard still off.  try version:

code: [select]

int ledpin = 13;

const int dot = 150;
const int dash = dot * 3;

int durations[] = {dot, dot, dot, dash, dash, dash, dot, dot, dot};

void setup() {
  pinmode(ledpin, output);
}

void loop() {
  (int = 0; < 9; i++) {
    flash(durations[i]);
    if (i == 2 || == 5)
      delay(dash - dot); // inter-letter additional time
  }
  delay(1000);
}

void flash(int duration) {
  digitalwrite(ledpin, high);
  delay(duration);
  digitalwrite(ledpin, low);
  delay(dot);
}

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