[sdiy] TI 76477 Space Invaders sound chip detailed analysis

Tom Wiltshire tom at electricdruid.net
Wed May 23 20:06:57 CEST 2018


The one I remember better is the SN76489 from the BBC Micro - this was a (slightly later?) more sophisticated digitally-programmable chip with three  square waves and a noise generator. Classic chip tunes.

> On 23 May 2018, at 17:00, info at synthcube.com wrote:
> 
> So I remember first being exposed to the SN76477 via Omni Magazine in what must have been sometime from about 1978-1980. We are offering a $25 store gift certificate to the first person to send us the article (or a link to it)-- i vaguely remember breadboarding a simple circuit with the SN76477 on  Radio Shack breadboard... 
> 
> Anyway, other than the Thomas Henry SN Voice and Supercontroller, I haven't seen many (or any) modular synth designs that use the chip... wondering why? 
> 
> They're still plentiful and relatively cheap given the range of capabilities... maybe we'll sponsor a module design contest around the SN76477 to see what emerges... 
> -------- Original Message --------
> Subject: Re: [sdiy] TI 76477 Space Invaders sound chip detailed analysis
> From: Tim Parkhurst <tim.parkhurst at gmail.com>
> Date: Wed, May 23, 2018 2:33 am
> To: cheater00 cheater00 <cheater00 at gmail.com>
> Cc: synth-diy mailing list <synth-diy at synth-diy.org>
> 
> You should also check out what the amazing Thomas Henry managed to do with the 76477. Even got a few octaves of CV response from it.
> 
> http://www.birthofasynth.com/Thomas_Henry/Pages/SN-Voice_main.html
> 
> 
> 
> Tim (if I had a quarter for every 76477-powered video game I played...) Servo
> 
> 
> 
> 
> 
> On Tue, May 22, 2018 at 9:16 PM, cheater00 cheater00 <cheater00 at gmail.com> wrote:
> 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):
> 
> http://www.righto.com/2018/05/inside-76477-space-invaders-sound.html
> 
> Here's an earlier anysis of the analog circuitry:
> 
> http://www.righto.com/2017/04/reverse-engineering-76477-space.html
> 
> I wonder if anyone has tried cloning the chip for synth use, with modern features like eg tuning.
> 
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at synth-diy.org
> http://synth-diy.org/mailman/listinfo/synth-diy
> 
> 
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at synth-diy.org
> http://synth-diy.org/mailman/listinfo/synth-diy
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at synth-diy.org
> http://synth-diy.org/mailman/listinfo/synth-diy




More information about the Synth-diy mailing list