12 Nov
2005
12 Nov
'05
12:33 a.m.
Subject: Re: FPGA VAX update, now DIY TTL computers
From: woodelf <bfranchuk at jetnet.ab.ca>
Date: Fri, 11 Nov 2005 16:14:58 -0700
To: General Discussion: On-Topic and Off-Topic Posts <cctalk at
classiccmp.org>
Chuck Guzis wrote:
74LS10 dip .25 at ea .17 at Q25 |74F10 dip .19 at ea .14 at Q25 |74HCT10 dip .25 at ea .18
at Q25
JDRmicrodevices.com
Even at a buck a chip if your only using 36 of them thats not painful.
Allison
Consider the very old Packard Bell PB250--22 bit
words, fewer than 400
transistors and 2500 diodes, 63 instructions. Power consumption about 40
watts, exclusive of I/O:
The trick, of course, is to use bit-serial methods. It seems to me that
one could greatly simplify construction of a homebrew machine that way.
We're not doing this for speed, right?
Not really that much, it is registers that hog all the logic gates.
I guess you would save only about 1/3 of your logic gates.
Cheers,
Chuck
I got playing around with 74xx logic and the best I can do for my CPU design
is about 36 chips for a two bit slice. Now who sells 3-input NAND's
and Gated
J/K F/F's cheap like they did in the 70's? And lots and lots of 14
pin Sockets!