Re: max IEC bus length and loading?

From: Vanessa Ezekowitz <vanessaezekowitz_at_gmail.com>
Date: Sun, 31 Oct 2010 15:57:06 -0500
Message-ID: <20101031155706.08e625c8@gmail.com>
On Sun, 31 Oct 2010 12:33:15 -0700 (PDT)
Gene Buckle <geneb@deltasoft.com> wrote:

> With that many potential devices available, I wonder why nobody has tried 
> making a floppy RAID with it or something. *laughs*  (It's been done with 
> USB floppy drives...)

As far as I know, there's nothing actually preventing higher data rates across the hardware, other than the ability of a stock C64 and (one) drive to process and store it in memory.  So, if you had an accelerator on the C64, and some kind of custom high speed serial protocol of course, you should be able to pull down data from many floppy drives at once.

Aside from the sheer amount of desk space such a thing would take, I can see one downside:  As a rough guess, any given drive would run at maybe 75% of the speed of a typical fastloader, because of protocol overhead from switching between drives.

If that 75% is correct and were to hold out across such a RAID, and you could write your code to run at the full 20x speed of the thing, a SuperCPU combined with all 25 IEC slots filled (hi Spiro! :-)  ) would just about max things out.

A 15x speedup over stock C64 code is probably more realistic, so roughly 20 drives might do it.

-- 
"There are some things in life worth obsessing over.  Most
things aren't, and when you learn that, life improves."
http://starbase.globalpc.net/~ezekowitz
Vanessa Ezekowitz <vanessaezekowitz@gmail.com>

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Received on 2010-10-31 21:00:30

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