[sdiy] Andromeda A6 hardware questions

[Tom Wiltshire]

I think we could go round and round with "that's loads" and  "that's  
not that much", so let me put some numbers on it.

I've been working on a digital/analog hybrid monosynth project for  
some three years now. It's taken that long because I've had to learn  
everything I needed to know as I went along. This includes:

Programming PIC/dsPIC processors
How to generate envelopes
How to generate LFOs and other modulation sources
How to talk SPI
How to get DACs running from a uP
How to talk to an external EEPROM
How to scan a keyboard
How to scan a panel full of knobs
How to talk to an LCD
How to design PCBs

As yet, I haven't written any MIDI handling code, done the patch  
storage, dealt with a sequencer, or written a menu system.

So, after three years, I've done about half the things on your list.  
I'm not claiming to be the most efficient person in the world (like  
most synthheads, I get wildly sidetracked by other projects) but I  
bet I go about as quickly as the next guy. I learned programming when  
I was a kid (including 6502 assembly language on a BBC micro, not a  
million miles from a modern PIC) , so at least I pick up new  
programming stuff pretty fast by most people's standards.

I don't want to sound like I'm poohpoohing the idea, because I'm not,  
but my personal experience leads me to believe that such a task would  
take some number of years (plural) and that anyone who is thinking of  
taking the job on had better have that in mind or they will simply  
get discouraged long before they could ever realistically hope to  
finish. Perhaps others can chime in with how long their own synth  
projects have taken to help us get an overview.
Every journey does start with a first step, but it helps to have some  
idea how far you're likely to be going before you set off so that  
you're better equipped for the trip! If it's a marathon, getting in  
training would be a good idea, or you're going to finish up collapsed  
by the roadside.

On a related note, Bruce Duncan and I took several months to design  
and program some of the new Modcan hybrid synth modules, and that was  
with two people (Bruce on hardware design, me doing software) and a  
single function. Multiply up by the number of functional units, then  
add a bit for all the integration.

Regards,
Tom


On 3 Mar 2010, at 11:24, cheater cheater wrote:

> Tom,
> as they say, every journey starts with the first step.
>
> On the other hand, I think you are overestimating the complexity of
> the andromeda's digital part. It's just some menus, midi, patch
> storage, a simple sequencer, voice assignment, and modulation. That's
> not *that* much.
>
> D.