[sdiy] Actel Fusion

[Scott Gravenhorst]

"Barry Klein" <Barry.L.Klein at wdc.com> wrote:
>Another platform that may have potential for us is the Actel Fusion.  I
>guess it has been out for some time but today is the first I had heard of
>it.  Basically an FPGA along with analog modules/channels and conversion.
>Here is a waveform generator app note:
>http://www.actel.com/documents/Fusion_Waveform_TB.pdf
>I wonder how much of the part this takes up?  There are temperature,
>voltage, and current sensing circuits in the chip as well.  Anyone have any
>experience with it and have an idea of chip costs and the fusion starter kit
>cost?  They talk of a choice between ARM and 8051 soft core processor for
>the FPGA too.  Would that be free or?  Got an idea of part costs?

Data here: http://www.actel.com/products/fusion/

The starter kit uses the 600K gate part.  "Distributed" RAM looks low at 108K bits and
block RAM at 24 blocks by 4608 bits also small at about 110K bits.  There is no mention
of dedicated hardware multipliers - a serious drawback for DSP.  The starter kit
literature mentions analog inputs, but I see nothing about DAC, only ADC...

Also, with  CoreMP7S, it seems that only 1/2 of the flipflops are usable and with 
CoreMP7Sd only 1/3 are usable.  Seems limiting to me unless you make very good tight use
of the core - which if I understand this, is an embedded processor and not necessary very
efficient for a synth-on-a-chip system.  

To compare - the Xilinx Spartan-3E Starter Kit can be endowed with a variety of MCU cores
such as the cost free PicoBlaze.  My experience says that PicoBlaze makes a very nice
full featured MIDI receiver and synth controller and it uses about 1% of the slice
resources of the FPGA and only one block RAM leaving MOST of the FPGA free for your synth
hardware.  MicroBlaze is a larger more powerful MCU, but is quite overkill for a MIDI
controller.  (My assembler code MIDI controller uses less than 1/2 of it's "ROM" (less
than 500 instructions), so there is room for all kinds of features).

Just my opinion.

-- ScottG

-------------------------------------------------------------

-- Scott Gravenhorst
-- GateMan-III - FPGA Based Monophonic MIDI Synthesizer with SVF
-- PolyDaWG/8 - FPGA Based 8 Voice Polyphonic MIDI Synthesizer
-- FatMan: home1.gte.net/res0658s/fatman/
-- NonFatMan: home1.gte.net/res0658s/electronics/
-- When the going gets tough, the tough use the command line.