Poly Keyboard Interfaces

[Niklas Lindberg]

On May 3 9:33am, Gene Stopp (gstopp at fibermux.com) wrote:
> Subject: Re[2]: Poly Keyboard Interfaces
>
>      The thing that really needs developing is a good multi-output
>      MIDI-to-CV converter. When I say "good" I mean different assignment
>      options, programmable split points, multiple MIDI channel support,
>      things like that. When I say "multi-output" I mean 8 CV's, 8
>      velocities, 8 release velocities (maybe), bend, mod, aftertouch,
>      volume, and some continuous controllers. Heck maybe 16 CV's and
>      velocities. If you want to get really fancy you can put an arpeggiator
>      in there somewhere (although I'd prefer to leave that in the
>      controller I think).

On May 6 09:22am, Colin Fraser (colinf at easter.euro.csg.mot.com) wrote:
>Subject: Re: Re[2]: Poly Keyboard Interfaces
>
>My own home-built midi to cv convertor has 32 cv outputs plus din sync.
>The first 16 channels are output to jacks, the last are hardwired to 4 SSM
>2024 quad vcas in a built in 8-2 mixer.
>Ouputs can be assigned to note velocity, controller or gate, on any midi
>channel, with upper and lower note limits to allow splits to be programmed.
>Pitch bend and aftertouch are TBI, as I don't have a controller keyboard with
>them.
>The DAC used is an 8-bit thing, but another convertor I built for a friend is
>shortly to be upgraded to 12 or 16 bits, to give a software selectable linear
>control voltage for a Korg.

I just felt compelled to tell you that I am actually working on something
like this for the moment. It will be a 16ch MIDI-CV converter housed in a
standard 19" 3HE card frame (It will be part of my modular). The hardware
is based on a 8031 CPU with 32K EPROM and 2K RAM. There will be a 16x2 char
display and a standard telephone-type keyboard for assigning of the CV-channels.
I will use a 12-bit DAC from Philips (Not tested yet though).

Each CV-channel has its own gate and shall be assignable to Pitch, Velocity,
Pitch bend, Continous controllers etc. (It remains to figure out how to
implement some of the features, though!)

I haven't yet written the software, which will be written in PLM-51 (an Intel
Microprocessor specific language), but I have made a little 'simulation' in
Pascal of the MIDI decoding part of the software which worked OK.

To aid in the software debugging process I've borrowed an ICE-51 (In Circuit
Emulator) from my work (It hasn't been used for ~ 5 years, so my boss felt it
was a good idea to get a check on it :->

I have borrowed some of the construction from Doepfers MCV1 & MCV8 (for which I
was kindly given schematics by Erik The Viking; Thanks!) but quite a bit of re-
arranging was necessary. For the moment I've built the PSU and put it in the Card
frame and next step is to layout the CPU-card and the Analog card.

If anyone should be interrested in this, I can supply whatever info needed as
soon as I get it working ( _If_ it will work, of course :-}

-Niklas
Niklas.Lindberg at ees.enator.se