[sdiy] More Xilinx 3E board comments

[James Patchell]

The FPGAs are ram based...turn off the power...and they erase.  Every time 
you power them up, they need to be reprogrammed.  Generally, this is done 
from a flash serial memory, which can be programmed via the JTAG...you will 
be able to see this when I demo the board.

Yes, the pico blaze would probably work just fine for a midi synth.

At 01:07 PM 6/8/2006 -0700, Scott Gravenhorst wrote:
>It's sounding like for a MIDI synth of actually whatever complexity, the 
>little Pico will
>do it, is that a fair assumption?  So quite literally, $150 will be 
>adequate for my
>needs, even polyphony I think and possibly multitimbral, again all in the 
>$150 setup
>using the 8 bit PicoBlaze... Yes?
>
>And may I assume that the FPGA can be "erased" and reprogrammed?  Is there 
>a limit to the
>number of times it can be reprogrammed?  I think I read that they FPGA 
>itself is like $9,
>so they are almost throw-away...  yes?
>
>
>James Patchell <patchell at cox.net> wrote:
> >Yes!....and more....
> >
> >For instance...You could easily build up a bank of 512 NCO sawtooth
> >oscilators...and it would barely be a hicup...with a sample rate of
> >97656.25hz @ clk=50MHz...
> >
> >why 512 oscillators?....because the RAM blocks can be configured as 512wx32b
> >
> >You would need two banks of these to make an NCO...one for the frequency
> >control, and the second for the accumulators...
> >
> >You then just need a 32 bit adder...and there you go....
> >
> >
> >Sampler...the thing has 32MB of ram on board...and 16MB of flash rom....
> >
> >filters...4 ram banks and you would have 512 biquad filters...(Frequency,
> >Q, Z1,Z2) (well, I hope 4 ram banks would do it :-)
> >
> >.....
> >
> >It only takes TIME!
> >
> >
> >At 01:56 PM 6/8/2006 -0400, Jeff Farr wrote:
> >>So, I'm getting very interested in this whole FPGA thing, but I seem
> >>to be right on Scott's level in terms of having any idea at all what
> >>they are about.  I can boil all my questions down to this tho: could I
> >>implement a simple sampler using the 150$ option?  How about a full
> >>blown sampler?  With analog modeled filters? ... ;)
> >
> >         -Jim
> >***************************************************************
> >Come to the 2006 Pacific Southwest Synth DIY meet
> >June 10, 2006 at the Goleta Library....
> >
> >Details:
> >http://www.oldcrows.net/~patchell/synthdiymeet.html
> >***************************************************************
> >http://www.oldcrows.net/~patchell
> >http://www.noniandjim.com/
> >***************************************************************
> >
> >
>
>---------------------------------------------------------
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>
>-- Scott Gravenhorst | LegoManiac / Lego Trains / RIS 1.5
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         -Jim
***************************************************************
Come to the 2006 Pacific Southwest Synth DIY meet
June 10, 2006 at the Goleta Library....

Details:
http://www.oldcrows.net/~patchell/synthdiymeet.html
***************************************************************
http://www.oldcrows.net/~patchell
http://www.noniandjim.com/
***************************************************************