[sdiy] Bus for digital patching of synths

[Maarten Halmans]

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.