[sdiy] New cheap FPGA development system

[ASSI]

On Donnerstag, 25. Mai 2006 20:56, Eric Brombaugh wrote:
> Want a fun starter project?
> * Go to Aaron Lanterman's pages, grab the schematics for the Synergy
> (http://users.ece.gatech.edu/~lanterma/synergy/)
> * Code it up in HDL for an FPGA

I've just read the paper by H. G. Alles in the 1980 IEEE Proceedings (I 
don't have access to the earlier Computer Music Journal paper that 
supposedly describes the engine in more detail).  Even so, there are a 
lot of useful insights in the IEEE Proceedings paper concerning the 
engine design.  A verbatim copy of the TTL grave of the synergy is 
probably ill-advised for any FPGA, in this particular case a 
combination of bit-slicing and slice-serial processing might work best.  
The Spartan3E is good for more than 200MHz in a nicely pipelined design 
that doesn't stress the routing ressources too much - that would mean 
640 partials if the Alles engine is taken as a blueprint and it likely 
fits several times in there to boot or offers an opportunity to 
significantly increase the sampling rate.  The multipliers aren't 
really useful for the partials IMHO, but could nicely do duty as "VCA" 
for the downmix of the voices.  Obvious food for thought is the 
"waveshape table", originally used for phase-to-sine conversion.  There 
are much better ROM compression methods than the one described, on the 
other hand one could put a real wavetable there...



Achim.
-- 
+<[Q+ Matrix-12 WAVE#46 Neuron microQkb Andromeda XTk sonic heaven]>+

SD adaptation for Waldorf microQ V2.22R2:
http://Stromeko.Synth.net/Downloads.html#WaldorfSDada