CPU design at the gate level

From: Richard Erlacher <edick_at_idcomm.com>
Date: Fri Nov 2 21:21:37 2001

With the <$1k cost, per each the $500 minimum is no problem. I get Cypress
CPLD's, by the way, from a distributor that has no such minimum, (wierd) but
they're hostile to coming in and picking the parts up rather than paying the $18
shipping for a $6 order. I long for the old queue at the will-call counter,
where you could swap stories and pick up your parts the day you ordered them,
paying sales tax, but no freight, and always being allowed to verify that the
parts were what you ordered. <sigh>

Dick

----- Original Message -----
From: "Ben Franchuk" <bfranchuk_at_jetnet.ab.ca>
To: <classiccmp_at_classiccmp.org>
Sent: Friday, November 02, 2001 6:22 PM
Subject: Re: CPU design at the gate level


> Richard Erlacher wrote:
> >
> > While it's true that TTL and work-alike CMOS is found everywhere, if you go
with
> > a parts list, you'll find you're unable to get a substantial range of parts
> > these days. You may be able to find the parts eventually, but the
investment in
> > shipping is prohibitive.
> >
> > Unfortunately for the builders of "one-of's," like me (spelled one-off's in
some
> > places, for reasons I don't understand), the programmable logic comes in
> > packages that are really inconvenient for that purpose. Nowadays, you're
> > required to use a 1000+ pin BGA package to get the quantity of logic that
you'd
> > like in a 44-pin PLCC. If you're really lucky with the fit, the device will
> > allow you to use 10% of the gate count the marketing guys said you're paying
> > for. The result is that you have to use a PGA package that lists for over
$1k
> > per part, or build an adapter board for the cheaper TQFP part, with a total
> > cost, when you're done, of over $1k per each anyway, and then, to make
matters
> > worse, only one in 7 of these adapter boards will turn out to be properly
> > soldered, so you waste 6 FPGA's costing $300 each. That's why product
> > development that once required a cash outlay of $500 now costs $500 million.
> >
> > Dick
>
> Don't forget the $500 minimum order per line item. I suspect you need
> all the 1000+ pins since
> only 50% of the pins are usable -- the power,ground and configuration
> pins take up a lot of space.
> Ben Franchuk.
> --
> Standard Disclaimer : 97% speculation 2% bad grammar 1% facts.
> "Pre-historic Cpu's" http://www.jetnet.ab.ca/users/bfranchuk
>
>
Received on Fri Nov 02 2001 - 21:21:37 GMT

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