RichardBronosky

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• What is LED1/A13? (addressing pins via variables)

  @RichardBronosky started

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  @Gordon replied
• What is LED1/A13? (addressing pins via variables)

  in General • 10 years, 11 months

  

  I'm very confused by the JS in Espruino for many reasons. I want to start off addressing this simple concern that I believe will also be useful to many others.

  I want to address pins whose names are stored in variables to make the code considerably cleaner.

  Consider this:

  led1 = function() {
    LED1.write(1);
    LED2.write(0);
    LED3.write(0);
    setTimeout(led2, 500);
  }
  
  led2 = function() {
    LED1.write(0);
    LED2.write(1);
    LED3.write(0);
    setTimeout(led3, 500);
  }
  
  led3 = function() {
    LED1.write(0);
    LED2.write(0);
    LED3.write(1);
    setTimeout(led1, 500);
  }
  
  setTimeout(led1, 500);
  

  That's pretty amateur. It would be some much cleaner/DRYer to do:

  clearInterval();
  
  led = function (n) {return (this)['LED'+n];}
  
  setInterval(function() {
    ledCount = 3;
    for (i=1;i<=ledCount;i++){
      l=led(i);
      if(l.read()){
        n = Math.wrap(i, ledCount) + 1;
      }
      led(i).write(0);
    }
    led(n).write(1);
  }, 500);
  

  It would be splendid if that would work in the same way this works:

  ono = function (n) {return (this)['ONO'+n];}
  ONO1 = 'a'
  ONO2 = 'b'
  ONO3 = 'c'
  
  ono(2)
  

  But it doesn't. It seems to require a limited switch/case.

  clearInterval();
  
  led = function(n) {
    switch (n){
      case 1:
        return LED1;
      case 2:
        return LED2;
      case 3:
        return LED3;
    }
  };
  
  setInterval(function() {
    ledCount = 3;
    for (i=1;i<=ledCount;i++){
      l=led(i);
      if(l.read()){
        n = Math.wrap(i, ledCount) + 1;
      }
      led(i).write(0);
    }
    led(n).write(1);
  }, 500);
  

  So, what and where are these LED variables an how can I address them programmatically?