<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
<p>Using option #2, I would make the software aware of the roll
speed - e.g. get pulses/ticks from the roll drive<br>
</p>
<p>Use the rate of the ticks to determine a minimum skip time based
on roll speed</p>
<p>- Oren<br>
</p>
<div class="moz-cite-prefix">On 11/10/22 7:56 PM, Jean-Pierre
Desrochers wrote:<br>
</div>
<blockquote type="cite"
cite="mid:000001d8f570$e18435b0$a48ca110$@oricom.ca">
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta name="Generator" content="Microsoft Word 15 (filtered
medium)">
<!--[if !mso]><style>v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style><![endif]-->
<style>@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}span.EmailStyle19
{mso-style-type:personal-reply;
font-family:"Calibri",sans-serif;
color:windowtext;}.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;
mso-fareast-language:EN-US;}div.WordSection1
{page:WordSection1;}</style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
<div class="WordSection1">
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Hi
all,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">My
Player piano reader project is going fine so far..<br>
Some little robotics stuff (stepper motors, sensors, etc..)
going on now..<br>
I’m now in the process of reading the small holes scrolling<br>
with the music paper rolls ‘sandwiched’ between Infrared
leds and 88 x Photo transistors (see the image below).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">The
actual music data appears on the paper as parallel lines of
small successive holes<br>
shown in blue below. Because of the need of paper sturdyness
for long duration notes the original paper punches<br>
made small successive holes in the same note line instead of
a steady cut in paper<br>
that could eventualy be damaged over time..<br>
That is shown by the blues dots below (successive holes).<br>
Now I need to read these constant note ‘ignoring’ all the
occuring small holes<br>
during these long duration notes..<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">The
second line shows what the reading Photo transistor ‘sees’<br>
and the third line shows an ideal reading stored in the
micro.<br>
<b>So far there are 2 ways I found to get close of the ideal
reading :<o:p></o:p></b></span></p>
<p class="MsoNormal"><b><span style="mso-fareast-language:EN-US">#1
Place a capacitor in parallel with each Photo transistors
to get rid of the ‘pulsating holes’ on a continuous note<o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span style="mso-fareast-language:EN-US">#2
Use software with separate counters to ‘skip’ the incoming
small pulses just enough not to miss any ‘real’ short
notes.</span></b><span style="mso-fareast-language:EN-US"><br>
My challenge here is that the paper roll speed will be a
variable one<br>
which could be varied from <b>1feet/min</b> up to <b>13feet/min</b>.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">That’s
a 1 to 13 ratio !!<br>
So method #1 using caps in parallel with the
photo-transistors (fixed RC time) will not be feasable (I
think).<br>
Is there another way you could think of to get rid of these
small pulses<br>
when necessary ? <br>
Thanks !<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><img
style="width:11.7187in;height:4.3333in" id="Image_x0020_2"
src="cid:part1.tD0dsTHY.KgdmuvN0@ix.netcom.com" class=""
width="1125" height="416"></span><span
style="mso-fareast-language:EN-US"><o:p></o:p></span></p>
</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
<pre class="moz-quote-pre" wrap="">_______________________________________________
Synth-diy mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Synth-diy@synth-diy.org">Synth-diy@synth-diy.org</a>
<a class="moz-txt-link-freetext" href="http://synth-diy.org/mailman/listinfo/synth-diy">http://synth-diy.org/mailman/listinfo/synth-diy</a>
Selling or trading? Use <a class="moz-txt-link-abbreviated" href="mailto:marketplace@synth-diy.org">marketplace@synth-diy.org</a>
</pre>
</blockquote>
</body>
</html>