[sdiy] Bus for digital patching of synths

[Neil Johnson]

Audio-grade I2S converters generally have poor DC performance, so you
wouldn't want to use them for pitch CVs.

Neil

On 8 November 2013 13:05, Maarten Halmans <diy at artefacts.nl> wrote:
>
> Lets say each module has 4 analog inputs and 4 analog outputs or a multiple
> of this number. The I2S signals(1 in and 1 out) are both connected to the
> fpga(fysical layer can be whatever you want, optical, differential,
> current).  The routing between in and outputs is done inside the FPGA. This
> way there is no high speed back bone and signals are at relativly low
> frequencies.  Yeah it is very complex thing to develop.
> Best,
>
> Maarten
>
> ----- Original Message ----- From: "cheater00 ." <cheater00 at gmail.com>
> To: "Maarten Halmans" <diy at artefacts.nl>
> Sent: Friday, November 08, 2013 1:21 PM
> Subject: Re: [sdiy] Bus for digital patching of synths
>
>
>> On Fri, Nov 8, 2013 at 12:13 PM, Maarten Halmans <diy at artefacts.nl> wrote:
>>>
>>> Hello all,
>>>
>>> AD & DA converters work with I2S,  why not create a I2S multiplexer in an
>>> FPGA? Add a Can or some similar bus to do communication between local
>>> microcontrollers on the modules and the main patching module.
>>>
>>> Cheers,
>>> Maarten
>>
>>
>> What the multiplexer in your example would do is to take the low-speed
>> I/O from a DAC, and interface it with the high-speed backbone. The
>> backbone would need a very high bit rate. However, an FPGA in itself
>> is just a simple device, it does not have the capability to drive a
>> long bus with a lot of devices on it, manage a TDM, perform link setup
>> and conflict resolution, manage physical resources, carry a homogenous
>> clock if that's needed, etc. All of that put together becomes a
>> networking standard and that is a lot of work to develop.
>>
>> D.
>
>
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at dropmix.xs4all.nl
> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy



-- 
--
http://www.njohnson.co.uk