[Flightgear-users] Rotary Encoder speed with nasal script

[Nicola Q. <ni...@qu...>]

Hi,

I connected an encoder with two outputs (A and B) at a Joystick Board 
(bodnar BU0836X). I used button 1 for wire A and button 2 for wire B.
Using xml and nasal script I get the right rotation (I want to move obs 
knob). Everything works fine only if I move the knob slowly. If I move 
the knob quickly, the result is uncertain.
It's pretty clear that I cannot intercept all the steps of the encoder.
Does anyone have any idea on how to fix it?
Thanks.

Here my files:

<button>
   <name>Encoder1A</name>
   <number>
    <unix>0</unix>
    <mac>0</mac>
    <windows>0</windows>
   </number>
   <desc>Encoder1 fase A</desc>
   <repeatable>false</repeatable>
   <binding>
    <command>nasal</command>
    <script>
       bodnar.encoder1("A", 1)
    </script>
   </binding>
  <mod-up>
   <binding>
    <command>nasal</command>
    <script>
       bodnar.encoder1("A", 0)
    </script>
   </binding>
  </mod-up>
  </button>

  <button>
   <name>Encoder1B</name>
   <number>
    <unix>1</unix>
    <mac>1</mac>
    <windows>1</windows>
   </number>
   <desc>Encoder1 fase B</desc>
   <repeatable>false</repeatable>
   <binding>
    <command>nasal</command>
    <script>
       bodnar.encoder1("B", 1)
    </script>
   </binding>
  <mod-up>
   <binding>
    <command>nasal</command>
    <script>
       bodnar.encoder1("B", 0)
    </script>
   </binding>
  </mod-up>
  </button>


Then this nasal script:

###############################################
var statusA = nil;
var statusB = nil;
var oldStatusA = nil;
var oldStatusB = nil;

var initBodnar = func() {
         print ("Loading bodnar.nas");
}

var encoder1 = func(button, status) {
         print (button , status);
         if(button == "A") {
                 statusA = status;
         }
         else if ( button == "B" ) {
                 statusB = status;
         }

         if(statusA == statusB) {
                 if(oldStatusA != statusA) {
                         direction("cw");
                 }
                 else {
                         direction("ccw")
                 }
         }
         else {
                 if(oldStatusA != statusA) {
                         direction("ccw");
                 }
                 else {
                         direction("cw")
                 }
         }
         oldStatusA = statusA;
         oldStatusB = statusB;
}

var direction = func(dir) {
         print (dir);
}

#############################################

-- 
Nicola Quargentan