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Theory?

PIC synth modules

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I'll be honest, I don't know shit about programming for a PIC chip, but I was wondering if anyone knew if the PIC chips would be good hosts for synth modules like oscillators, VCF's etc.  Similar to the chips CEM made for Sequential.  If not, does anyone know a chip that CAN host those kinds of programs?

Secondly, is it possible to code for these chips in Perl or are C and ASM my only options?

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I believe that the PIC can act as an oscillator, it can certainly generate pulse waves.

There is a project called the AVR synth which has square wave oscillators and digitally controlled filters and envelopes. Google AVRSynth for more info.

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I believe that the PIC can act as an oscillator, it can certainly generate pulse waves.

There is a project called the AVR synth which has square wave oscillators and digitally controlled filters and envelopes. Google AVRSynth for more info.

Found it actually.  And then I found something Thorsten said about the AVR chips and why he still uses the PIC chips.

I've heard good things.

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The CEM and SSM chips from old synths are analogue - all analogue oscillators, filters etc, just etched in silicon.  Someone had a aproject around here to make a synth using a few PICs, one for oscillator, one for filter etc.  To emulate analogue in software (which is what a PIC would do) might be beyond a PIC if you want to do it all on one PIC,

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The CEM and SSM chips from old synths are analogue - all analogue oscillators, filters etc, just etched in silicon.  Someone had a aproject around here to make a synth using a few PICs, one for oscillator, one for filter etc.  To emulate analogue in software (which is what a PIC would do) might be beyond a PIC if you want to do it all on one PIC,

Or, using my powers of alchemy to turn all my pencils into gold, I can build a factory and start building module chips again.

The only drawback is I would have to face off against Dave Smith and his mutant zombie robot baby army.

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Or, using my powers of alchemy to turn all my pencils into gold, I can build a factory and start building module chips again.

The only drawback is I would have to face off against Dave Smith and his mutant zombie robot baby army.

LMAO  ;D ;D ;D

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I started working on such a beast a while back, actually.  It wouldn't be a clone of the AVRsynth, but some of the concepts are similar.  Due to the complexity, I've been scaling back the design - it should end up as a simple module controlled via SPI:  a PIC, resistor ladder output (woo, cheap!), and an opamp.  That's about it.  Two wavetable oscillators, a "filter", an envelope and/or LFO or three, and a few other features.  Lo-fi gritty goodness.  I had already prototyped the wavetable oscillators in Labview, so I have an idea of what they should sound like.

For whatever weird reason, I just became interested in my defunct project and came to check the forums here...  There were a couple of samples down near the bottom 1/4 of this page:  http://www.midibox.org/forum/index.php?topic=3713.15

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Hey AM. Glad to see you getting your feet back on the ground mate :) Have you seen the 'soundgin' chip yet? I'd like to see a dedicated synth though ... Look forward to seeing how you go :)

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Hey stryd_one!

Yeah, it's been a while since I last stopped by.  In the past year my mother-in-law died, my wife and I bought a house, moved, renovated, and then my brother-in-law died.  Really crappy  :'(

Anyways, I've started to get off my butt and realized that if I never work on any of my projects, then they'll never get done!  I managed to track down my Labview code for the DPS audiotest prototype, and made sure it still worked.  The oscillators sound great, but the filter was still buggy.  For now I think I'll just work on the "VCA", envelopes, and LFOs.  Then I'll get all the modulation algorithms, etc. working before I worry too much about the filter.  Worst case scenario, I'll just leave out the lousy digital filter, and people can use a nice fat analog filter of their choice.  I'm thinking something like:  1 core, 8 DPS modules, AOUT_LC, analog filter.

That said, I haven't determined just how many oscillators to stuff into each DPS module - it may even be possible to do them with a lower-cost PIC (eg 18F25J10, which is only $4.57 CAD @ Digikey, or $2.60 CAD in qty 25).  Regardless there should be at least two wave oscillators (with anywhere from 64 to 256 waveforms available), each with a suboscillator (square or saw waveform).  Or maybe four oscillators, I'm not really sure yet!  I also may end up going with IIC instead of SPI, since it appears that there is some decent support in MIOS for IIC-connected modules.  Don't want to rock the boat, or create extra work for myself  ;)

Whoops, didn't mean to thread-hijack.  I'll have to update my original thread once I've gotten an ENV / gate / VCA working...

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Hi Andrew,

Welcome back.  Sorry to hear you've had a tough year.

Have you checked out the new toy yet?

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