[sdiy] MIDI DCOs

[Mark Smith]

Sounds like what I did originally, before adding the programmable current source and integrator cap to make a sawtooth.

> -----Original Message-----
> From:	Fredrik Carlqvist [SMTP:ifrc at iar.se]
> Sent:	Friday, January 09, 2004 1:36 PM
> To:	synth-diy at dropmix.xs4all.nl
> Cc:	'Fredrik Axtelius'
> Subject:	RE: [sdiy] MIDI DCOs
> 
> 
> I am using a PIC18. There is a really neat way of using Timer1 and CCP1 to
> form the DCO. Having two interrupt levels makes it possible to combine a
> stable DCO with a MIDI receiver. It works really great. I'm working on
> adding sawtooth to the existing PWM output.
> 
> Fredrik Carlqvist
> 
> 
> -----Original Message-----
> From: owner-synth-diy at dropmix.xs4all.nl
> [mailto:owner-synth-diy at dropmix.xs4all.nl] On Behalf Of Fredrik Axtelius
> Sent: Friday, January 09, 2004 13:11
> To: synth-diy at dropmix.xs4all.nl
> Subject: RE: [sdiy] MIDI DCOs
> 
> 
> Hi!
> 
> I'm planning to build a PIC based DCO.
> Care to share the source?
> 
> /frax
> 
> btw, got the following when I tried to email you directly.
> 
> The original message was received at Fri, 9 Jan 2004 13:04:43 +0100 
> (CET)
> from d1o265.telia.com [217.208.188.241]
> 
>    ----- The following addresses had permanent fatal errors -----
> <Mark.Smith at pace.co.uk>
>     (reason: 571 5.0.0 Domain Rejected: see 
> http://ftp.pace.co.uk/ibf.html)
> 
>    ----- Transcript of session follows -----
> ... while talking to mailhost.pace.co.uk.:
> >>> DATA
> <<< 571 5.0.0 Domain Rejected: see http://ftp.pace.co.uk/ibf.html 554 5.0.0
> Service unavailable <<< 503 5.0.0 Need RCPT (recipient)
> 
> 
> 
> citerar Mark Smith <Mark.Smith at pace.co.uk>:
> 
> >
> > 	>Has anyone come up with a DIY, MIDI controlled, DCO bank?
> Something like
> > 	>8 DCO's that will polyphonically follow MIDI and send out a
> > 	>corresponding Gate with each note on.
> >
> > 	I have done this for a single voice channel on my 303 clone,
> you could use
> > 8 processors or use an fpga to do this 8 times.
> >
> > 	http://www.meadowfield.freeuk.com/synth/tb303sch.PDF
> >
> >
> > 	>I envision something like that with a Wiard Miniwave after
> it, that
> > 	>could be used to build a DCO based (no tuning problems) poly
> synth along
> > 	>the lines of a Juno 106, but with whatever waveshaping,
> Filters, VCA's
> > 	>and envelope's you want.
> >
> > 	this is what I did with a standard 303 backend, but I could
> have used the
> > juno-6 / SH-101 backend...
> >
> > 	mark
> >
> >