[hpsdr] Mercury

[John B. Stephensen]

That's also an issue. I need to clock the filter engines at 147.456 MHz.
This required pipelined 18x25-bit multipliers plus 3-stage pipelined
accumulators on the Xilinx XC3S400. The high precision coefficients support
large amounts of decimation in each filter. A slower clock would require
processing I and Q samples in parallel, rather than serially as I do now.
The number of multipliers then doubles.

73,

John
KD6OZH

----- Original Message ----- 
From: "KD5NWA" <kd5nwa at cox.net>
To: "John B. Stephensen" <kd6ozh at comcast.net>
Sent: Sunday, June 11, 2006 03:54 UTC
Subject: Re: [hpsdr] Mercury


> They are also faster parts.
>
> At 10:43 PM 6/10/2006, you wrote:
> >***** High Performance Software Defined Radio Discussion List *****
> >
> >The RAM is a problem. I need lots of it for filters, the FFT and
traceback
> >memory. The extra RAM in the smaller Xilinx parts is a big help for DSP.
> >
> >The largest Xilinx part available in a non-BGA package now appears to be
the
> >XC3S500E and is $26 (1-24 pieces) at Nu Horizons. This provides more than
> >twice the memory of the Altera, part plus a few more multipliers and
logic
> >elements.
> >
> >73,
> >
> >John
> >KD6OZH
> >
> >----- Original Message -----
> >From: "Lyle Johnson" <kk7p at wavecable.com>
> >To: "John B. Stephensen" <kd6ozh at comcast.net>
> >Cc: "Philip Covington" <p.covington at gmail.com>; <hpsdr at hpsdr.org>
> >Sent: Sunday, June 11, 2006 03:24 UTC
> >Subject: Re: [hpsdr] Mercury
> >
> >
> > > > It would be nice to have at least as many resources as a Xilinx
XC3S400
> >(16
> > > > 18k dual-port RAMs, 16 18x18 multipliers and 7200 logic elements).
> > >
> > > The Altera EP2C8 is the largest Cyclone II device I can find in a
> > > non-BGA package.  It has 165,888 bits of SRAM (36 blocks of 4K bits),
18
> > > 18x18 multipliers and 8256 logic elements.  $24 in singles from the
> > > Altera online store.
> > >
> > > 73,
> > >
> > > Lyle KK7P
> > >
> >
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>
> Cecil Bayona
> KD5NWA
> www.qrpradio.com
>
> "Windows the worlds most successful software virus"
>


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