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<p class="MsoNormal">I got the chip from RS in the 70’s. It was fun to play with but compared to what one can do today, it’s just a historical novelty today. I still have that chip plus the folding paper that was stapled to the back of the card.<o:p></o:p></p>
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<p class="MsoNormal">JJS<o:p></o:p></p>
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<p class="MsoNormal"><b>From:</b> Synth-diy <synth-diy-bounces@synth-diy.org> <b>
On Behalf Of </b>cheater00 cheater00<br>
<b>Sent:</b> Tuesday, May 22, 2018 9:16 PM<br>
<b>To:</b> synth-diy mailing list <synth-diy@synth-diy.org><br>
<b>Subject:</b> [sdiy] TI 76477 Space Invaders sound chip detailed analysis<o:p></o:p></p>
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<p class="MsoNormal">I've just found this while surfing the internet, an analysis of the 76477 sound chip's digital sound circuits. This includes the unique shift-register based noise circuit, as well as the noise filter circuit (which is analog):<o:p></o:p></p>
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<p class="MsoNormal"><a href="http://www.righto.com/2018/05/inside-76477-space-invaders-sound.html">http://www.righto.com/2018/05/inside-76477-space-invaders-sound.html</a><o:p></o:p></p>
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<p class="MsoNormal">Here's an earlier anysis of the analog circuitry:<o:p></o:p></p>
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<p class="MsoNormal"><a href="http://www.righto.com/2017/04/reverse-engineering-76477-space.html">http://www.righto.com/2017/04/reverse-engineering-76477-space.html</a><o:p></o:p></p>
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<p class="MsoNormal">I wonder if anyone has tried cloning the chip for synth use, with modern features like eg tuning.<o:p></o:p></p>
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