[sdiy] Parallel 8 Bit DACS?

[Jack Jackson]

Hi Brian,

Here's an example of what I meant with daisy chaining on the Solton Programmer EPROMs

http://soundsofthedot.com/images/daisy.png

> CC: synth-diy at dropmix.xs4all.nl
> From: brianw at sounds.wa.com
> Subject: Re: [sdiy] Parallel 8 Bit DACS?
> Date: Mon, 9 Dec 2013 22:28:37 -0800
> To: jackdamery at hotmail.co.uk
> 
> 
> On Dec 9, 2013, at 01:16, Jack Jackson wrote:
>> Thanks for your reply. I wasn't really thinking of building 
>> anything soon, the Jupiter and another project are in the pipeline 
>> first. Just got interested in the technology. It seems rather neat, 
>> apart from the daisy chaining of eproms (or at least that's what it 
>> looks like).
> 
> Maybe we're using the term "daisy chaining" differently, but I can't 
> imagine any reason why you'd want to daisy chain the EPROMs 
> themselves. Are you thinking that your samples will be too long for a 
> single EPROM? With today's large EPROM sizes, I doubt you'll need 
> more than one per voice.
> 
> The counters might certainly need to be daisy-chained if you need 
> more address bits than a single counter chip can provide. The only 
> other solution is to use an FPGA where you can build up the counter 
> of the size that you need, but then they're just single-bit toggles 
> that are daisy-chained for the address bus width.
> 
> You certainly want a separate counter and EPROM per voice, unless 
> you're really clever with multiplexing.
> 
> 
>> How would one go about interpreting linn drum binaries to work on 
>> linear DACs?
> 
> Who has schematics for the Linn drum machines? That would hold most 
> of the clues to binary interpretation.
> 
> Wasn't there a thread recently on Analogue Heaven or Synth DIY about 
> interpreting some drum machine ROM format? I can't remember the 
> model, but somebody put a lot of work into it.
> 
> Brian Willoughby
> Sound Consulting
>