[sdiy] Hardware convolution box?

[Eric Brombaugh]

On 02/13/2017 01:06 PM, Olivier Gillet wrote:
>> I'd love to know what DSP the Z-DSP uses, I suspect it's an ARM based chip,
>> but I could be wrong.
>
> It's a Spin Semi FV-1.

Yep - the FV-1 is a fun part. I've done a bit of coding & hardware using 
that and it packs a whole lot of nifty features into a small space. 
Keith Barr did a fantastic job in condensing so much of his experience 
down into a very useful chip.

That said, it's by no means a "powerful" DSP - rather it is fairly 
run-of-the mill tech that's been specifically tuned to do one narrow job 
well. The instruction set is aimed at audio DSP, and more specifically 
delays and IIR filters. Step outside that and you lose most of the 
advantages.

With a minimal understanding of the FV-1 CPU architecture and 
instruction set I've been able to port some of the open-source effects 
programs for the FV-1 to the STM32F3 and F4 processors and they run fine 
in that architecture (even at higher sample rates in some cases). I 
wouldn't say that general purpose ARM MCUs are behind it in performance 
- they just don't integrate an audio-grade codec onto the same die as 
the FV-1 does.

Eric