[Fpga-synth] Modular approach

[Scott Gravenhorst]

"The making of synthesizers in FPGAs." wrote:
>Hi all
>
>A recent off SDIY list discussion has got me thinking about FPGA  
>implementation.
>
>One way to implement a software based modular, the Nord being the  
>starting point for the discussion, would be to have a list of elements  
>where each element is a structure that contains an ID for the  
>processing element to be used, pointer to inputs (audio and control),  
>outputs (for the pointer to pointer too) and element storage,  
>parameters and so on. The processing is simply to run down the list  
>passing a pointer to the entry to the processing element. A  
>configuration editor would create the list being separated from the  
>software creation task.
>
>Over the last few days I have been trying to conceive an FPGA based  
>equivalent. The above processing method does not lend itself to FPGA  
>deployment but as yet I can not really see an FPGA version.
>
>I would appreciate some input. I like the concept of processing  
>elements that get implemented once and used a number of times,  
>configured at runtime rather than at build time. Perhaps this concept  
>is not really suited to FPGAs.
>
>Thanks everyone
>
>Veronica in foggy Port Alberni, 0ºC

I had thought something like this could be done at the source level, but that is
impractical due to long compile times.  

After reading this and Eric's reply, I wonder if a multiple FPGA approach might work,
where several small FPGAs would contain filters, NCOs, EGs et al and a larger FPGA
with lots of I/O might be used as a crossbar?

-- ScottG in dreary Los Angeles with a predicted high for today of 64ºF (17.8ºC)
________________________________________________________________________
-- Scott Gravenhorst
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