<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=utf-8"><meta name=Generator content="Microsoft Word 14 (filtered medium)"><style><!--
/* Font Definitions */
@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;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri","sans-serif";
mso-fareast-language:EN-US;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 90.0pt 72.0pt 90.0pt;}
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]--></head><body lang=FR-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-CA>>That's really cool. Thanks for sharing this !<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Calibri","sans-serif";color:#376092;mso-style-textfill-fill-color:#376092;mso-style-textfill-fill-alpha:100.0%'>Thanks Jean !<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA>>Could you explain what the pic do ? Is it for the Sync ?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Calibri","sans-serif";color:#1F497D'>Well you are right.<br>The PIC’s job is mostly to get all the VGA timing pulses accurate<br>with no jitters. It generates pulses for the video line width, Horizontal sync,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Calibri","sans-serif";color:#1F497D'>Vertical sync, Frame width, etc.. If you look at the available C code you will find<br>lots of delay loops and insertion of assembly codes for precise pulse widths like:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Calibri","sans-serif";color:#1F497D'> *************************<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'>while(1)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> for(line_counter=0;line_counter<600;line_counter++) // 600 DECI = 0x0258, 300 DECI = 0x012C<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> </span><span style='font-family:"Courier New";color:#1F497D'>{<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New";color:#1F497D'> // delay 20 usec (D)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> // check line# here<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> if(line_counter<0x0200)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> delay_us(4);<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> #asm<o:p></o:p></span></p><p class=MsoNormal style='margin-left:35.4pt;text-indent:35.4pt'><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'>nop<o:p></o:p></span></p><p class=MsoNormal style='margin-left:35.4pt;text-indent:35.4pt'><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'>nop<o:p></o:p></span></p><p class=MsoNormal style='margin-left:35.4pt;text-indent:35.4pt'><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'>nop<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> #endasm<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> }<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> else<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> delay_us(3);<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> #asm<o:p></o:p></span></p><p class=MsoNormal style='margin-left:35.4pt;text-indent:35.4pt'><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'>nop<o:p></o:p></span></p><p class=MsoNormal style='margin-left:35.4pt;text-indent:35.4pt'><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'>nop<o:p></o:p></span></p><p class=MsoNormal style='margin-left:35.4pt;text-indent:35.4pt'><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'>nop<o:p></o:p></span></p><p class=MsoNormal style='margin-left:70.8pt'><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'>nop<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> #endasm<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'> }<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Courier New";color:#1F497D'>Etc..<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Calibri","sans-serif";color:#1F497D'>*************************<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Calibri","sans-serif";color:#1F497D'>The rest of the schematic is for audio signal formatting to pulses<br>and color selection from a 7 positions rotary switch..<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Calibri","sans-serif";color:#1F497D'>I do appreciate you had interest for this project.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Calibri","sans-serif";color:#1F497D'>Thanks again.<br><br><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Calibri","sans-serif";color:#1F497D'>JP<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>De :</span></b><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Jean Bender [mailto:lofideadbeat@gmail.com] <br><b>Envoyé :</b> 7 mai 2018 16:41<br><b>À :</b> Jean-Pierre Desrochers<br><b>Objet :</b> Re: [sdiy] My 13 </span><span lang=FR style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>years old VGA Oscilloscope project on Youtube..<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Wow !!<o:p></o:p></p><div><p class=MsoNormal>That's really cool. Thanks for sharing this !<o:p></o:p></p></div><div><p class=MsoNormal>Could you explain what the pic do ? Is it for the Sync ?<o:p></o:p></p></div><div><p class=MsoNormal>Thanks !<o:p></o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Le 7 mai 2018 10:23 PM, "Jean-Pierre Desrochers" <<a href="mailto:jpdesroc@oricom.ca">jpdesroc@oricom.ca</a>> a écrit :<o:p></o:p></p><p class=MsoNormal>Hi list,<br><br>In 2015 I built a small VGA oscilloscope and then put it aside for a while..<br>(a long while...) Then Yesterday I rediscovered it by means of using it<br>along with an external<br>and complex audio waveform driving it.. (Using my DOTCOM modular as an audio<br>source)<br>I've been able to create some weird VGA waveforms.. have a look here:<br><a href="https://www.youtube.com/watch?v=VKMjb3CpOCE&feature=youtu.be" target="_blank">https://www.youtube.com/watch?v=VKMjb3CpOCE&feature=youtu.be</a><br><br>This is an open source project so for anybody interested to go <br>further or just build it, all the needed files are available here:<br><a href="http://www.arcenson.com/projects/VGA_Oscilloscope/" target="_blank">http://www.arcenson.com/projects/VGA_Oscilloscope/</a><br><br>Enjoy !!<br>By the way I just bought this morning an old VGA 15" 4:3 Samsung display <br>For $10.00 to do some tests.. Really appreciate it !<br><br>JP<br><br><br>_______________________________________________<br>Synth-diy mailing list<br><a href="mailto:Synth-diy@synth-diy.org" target="_blank">Synth-diy@synth-diy.org</a><br><a href="http://synth-diy.org/mailman/listinfo/synth-diy" target="_blank">http://synth-diy.org/mailman/listinfo/synth-diy</a><o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>