Thanks Steven and Andy,

I found a temporary inelegant solution using the host console. 

It works in local but when I test it online p2 is set with a delay and do not correspond to the score instructions : for example if I trigger the score function three seconds after the "Csound ready" message, the value of p2 equals 3 while in the score line p2 equals 0. 
Certainly mistakes or approximations in my code...

html:



 

csound:

instr 1

; instrument code, etc.

; sprintf and puts to show scorelines in console, the "scoreStatement" for filtering messages later
Stest sprintf "%s %s %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f", "scoreStatement", "i", p1, p2, p3, p4, p5, p6, p7, p8, p9, p10, p11, p12, p13, p14, p15, p16, p17, p18, p19, p20, p21, p22
puts Stest,1 

endin

Javascript:

    var count = 0;
    var scoreOn = false;

    function handleMessage(message) {
      var element = document.getElementById('console');
      element.value += message;

      var searchFilter = "scoreStatement"; filter only i instructions messages 
      if (scoreOn == true) {
      message.includes(searchFilter) == true;
      var parse = document.getElementById('display');
      parse.value = message;
      parseInstructions();
      }

      element.scrollTop = 99999; // focus on bottom
      count += 1;
      if (count == 1000) {
        element.value = ' ';
        count = 0;
      }
    }

  function parseInstructions(){
      var receiveStatement = document.getElementById('display').value;
      var scoreDatas = receiveStatement.split(" ").slice(2);  convert the filtered messages in array

      /*the rest of the code parse and send values of scoreDatas to each html item using for loop on the array and document.getElementById().value*/
 }

    function score() {
      scoreOn = true;
      init();
      ctrl();
      csound.ReadScore(document.getElementById("scoreTest").value);
      if (started == false) {
        CsoundObj.CSOUND_AUDIO_CONTEXT.resume();
        started = true;
      }
    }

For test online, just click on score button: http://csound.jeanbasilesosa.com/

Maybe have you an idea about my p2 problem when I trigger the score function? 

Mery christmas,

Jean Basile

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