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Re: [f-cpu] Something new to play with :)

hi !
... i just woke up ...

Michael Riepe wrote:
> On Tue, Sep 25, 2001 at 03:00:49AM +0200, Yann Guidon wrote:
> [...]
> > > It means: 66 MHz is pretty good (for an FPGA).  Although, know you
> > > mentioned it... I *may* be able to do even better ;)
> > i *knew* it ;-) i knew that you had something in mind and i know that
> > it is possible to do better (hence my personal research)
> I'll have to investigate the 4x4 approach more closely.  For an FPGA,
> 2x2 cells may make sense, too (especially when you have cells with 3-4
> inputs and 2 outputs that can route the bits either parallel or crossed).
> Other things that may result in a speed-up:
>         - separate sign extension from the right shifter
>         - improve/rewrite stage 2 decoder
>         - separate shift and rotate operations (beware! code duplication)
code duplication does not necessarily end up with faster silicon...

> [...]
> > > > ggggrrrrrr i'll have to look at the sources :-)
> > > Good idea ;)
> > let's add an optical output to my flying calf first :-P
> wtf is a "flying calf", and why does it need an optical output?
> .o( pigs don't fly, so why should calves? )
"flying calf" is a 20-bit stereo A/D SPDIF (coax) converter from Midiman
(i got two of them in a bargain).
however, minidisc recorders have an optical input. so i have to hack
an optical output to the Midiman converter. With this stuff, i finally
can record with 60db SNR :-))) portable minidiscs suck when you push the
sensitivity of the microphone input. My MZR-30 has decoupling problems,
the internal A/D is not protected from the electric motor power noise.
Now, all the conversion will be done externally, which removes the
other limitation : once you started to record a track, you can't change
the sensitivity. And the flying calf has a 6 LED level indicator per channel,
it's more practical in the dark ;-)
did i say i'm an audio freak ?

>  Michael "Tired" Riepe <Michael.Riepe@stud.uni-hannover.de>
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