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</o:shapelayout></xml><![endif]--></head><body lang=FR-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>></span><span lang=EN-CA> Are you handling running status and note off sent as zero velocity note on?<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'>Yes I handle both.<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'>Running status are ignored here,<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'>And I consider both NOTE OFF and NOTE ON with zero velocity<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'>As the end of a note.<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><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=FR style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>De :</span></b><span lang=FR style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> dougall [mailto:dougalli@gmail.com] <br><b>Envoyé :</b> 19 mars 2020 21:06<br><b>À :</b> eidorian@aladan.net<br><b>Cc :</b> Jean-Pierre Desrochers; Synth-diy@synth-diy.org<br><b>Objet :</b> Re: [sdiy] MIDI I/O c code..<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Are you handling running status and note off sent as zero velocity note on?<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>-d<o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Fri, 20 Mar 2020 at 11:55, <<a href="mailto:eidorian@aladan.net">eidorian@aladan.net</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><div><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>Sorry, I don't have example code for you, but here is some analysis that I hope might help point you in the right direction:<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>20MHz / 31,250Hz => ~640 instructions per MIDI data bit, or 6,400 instructions per MIDI data byte. That's quite a lot of instruction execution time between notes, so I'd be checking the efficiency/optimisation of the code.<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>How long is it taking to update the analog outputs and do other processing? If it's updating all 8 CVs via a "slow" protocol like I2C every time it loops then that might be taking a while, and maybe you need a different approach (i.e. only update a CV output when it changes).<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>How have you implemented the FIFO? Do you have locking to ensure the interrupt isn't writing to it while the main loop is updating it?<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>Create a debug version that has checks on the FIFO size in the interrupt, and sets an LED on if it overflows, so you can confirm for certainly whether or not that's the problem.<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>What I do (with 30+ years of programming experience) is pretend I'm the CPU, and "execute" the code in my head (or on paper if complex) in order to try to work out what unplanned or unexpected things might be happening to cause the problematic behaviour.<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>Cheers,<br>A.<o:p></o:p></span></p><div id="gmail-m_5822220122528591338signature"><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>---<o:p></o:p></span></p><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'> <o:p></o:p></span></p></div></div><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p id="gmail-m_5822220122528591338reply-intro"><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>On 20-03-2020 11:14, Jean-Pierre Desrochers wrote:<o:p></o:p></span></p><blockquote style='border:none;border-left:solid #1010FF 1.5pt;padding:0cm 0cm 0cm 5.0pt;margin-left:0cm;margin-right:0cm'><blockquote style='border:none;border-left:solid #1010FF 1.5pt;padding:0cm 0cm 0cm 5.0pt;margin-left:0cm;margin-right:0cm'><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'> <o:p></o:p></span></p></div></blockquote></blockquote><blockquote style='border:none;border-left:solid #1010FF 1.5pt;padding:0cm 0cm 0cm 5.0pt;margin-left:0cm;margin-right:0cm'><div id="gmail-m_5822220122528591338replybody1"><div><div><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>I’m working on a new polyphonic MIDI to CV module (8 voices).<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>So far I did my tests with an old PIC16F887 @ 20Mhz micro I had on hand.<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>I use a USART interrupt driven c function to ‘catch’ all the incoming MIDI bytes.<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>My code is pretty fast, but still, since I only read one MIDI channel (1-16) at the time <br>when I play very fast chords on an external keyboard<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>all the notes are read in the incoming queue but sometimes<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>I get stuck notes or unread ones..<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>Same thing happens when playing MIDI files on Cakewalk SONAR <br>feeding my prototype with a MIDI cable.<br>The interrupt function grabs each incoming byte and put them<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>In a receive buffer of 32 bytes and the main () reads and treats them in a FIFO manner<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>Later in the main loop.<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'> <o:p></o:p></span></p><p><em><span style='font-family:"Verdana","sans-serif"'>-Would a 32Mhz micro do a difference in the USART interrupt reading speed ?</span></em><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p></o:p></span></p><p><em><span style='font-family:"Verdana","sans-serif"'>-And is 32 bytes long enough for the RxBuffer to handle a 6 voices chords ?</span></em><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p></o:p></span></p><p><em><span style='font-family:"Verdana","sans-serif"'>-And finaly I checked the web for a ‘decent’ C code examples</span></em><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p></o:p></span></p><p><em><span style='font-family:"Verdana","sans-serif"'> for MIDI reception (MIDI Tx is much easier to implement) with no success..</span></em><i><span style='font-family:"Verdana","sans-serif"'><br><em><span style='font-family:"Verdana","sans-serif"'> ‘Obscure’ Arduino libraries all around with no explainations of its inner code.</span></em></span></i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'> <o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>Did anybody use good C code available ?<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>JP<o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'> <o:p></o:p></span></p><p><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><a href="mailto:Synth-diy@synth-diy.org" target="_blank">Synth-diy@synth-diy.org</a><o:p></o:p></span></p></div></div></div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>_______________________________________________<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></span></p></div></blockquote></div><p 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