From: lawrence@c896388-c.attbi.com (Lawrence Statton N1GAK/XE2) Newsgroups: alt.folklore.computers Subject: Core Memory Demonstration Project Summary: What would be a good way to build a demonstration project for core Message-ID: User-Agent: slrn/0.9.6.4 (Linux) Lines: 31 NNTP-Posting-Host: 12.236.27.224 X-Complaints-To: abuse@attbi.com X-Trace: rwcrnsc54 1054078708 12.236.27.224 (Tue, 27 May 2003 23:38:28 GMT) NNTP-Posting-Date: Tue, 27 May 2003 23:38:28 GMT Organization: AT&T Broadband Date: Tue, 27 May 2003 23:38:28 GMT Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!news.imp.ch!news.imp.ch!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!small1.nntp.aus1.giganews.com!border3.nntp.aus1.giganews.com!nntp.giganews.com!wn14feed!worldnet.att.net!204.127.198.203!attbi_feed3!attbi.com!rwcrnsc54.POSTED!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:139736 So, I was thinking as I was walking down the street the other day, about some of the technologies that have long-gone, and how they might be entertaining and even educational. Towit: How would an engineer go about building a few bits of core memory today, given that core planes aren't as easy to come by as they once were. I know that Amidon makes a wide variety of ferrite cores and beads for the choke market, so they would probably be a good place to start. The question is: What are the critical variables for the magnetics (not even CLOSE to my strong suit), and is there any overlap in the product lines? I think a demonstration circuit of sixteen bits (4 x 4) of honest-to-god core memory would be a great tool for discussion about the progression of computer technology. And it has the great advantage of having a physical artifact for each bit of memory, yet is entirely solid-state (ignoring any spurious magneto-restrictive characteristic of the cores [1]). --L echo 'lawrenabae@abaluon.abaom' | sed s/aba/c/g [1]: In my nova-1200 between the switching power supply, and the magneto-restrictive effects of the core memory, you could "hear" where in the compile-link-assemble phase the machine was in. All-in-all very cool. ###### From: ararghNOSPAM@NOT.AT.enteract.com Newsgroups: alt.folklore.computers Subject: Re: Core Memory Demonstration Project Date: Tue, 27 May 2003 19:07:05 -0500 Organization: Not Really! Lines: 28 Message-ID: References: NNTP-Posting-Host: tcr199.dynip.ripco.net Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: e250.ripco.com 1054080614 12107 209.100.226.199 (28 May 2003 00:10:14 GMT) X-Complaints-To: usenet@ripco.com NNTP-Posting-Date: Wed, 28 May 2003 00:10:14 +0000 (UTC) X-Newsreader: Forte Agent 1.92/32.572 Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!news.imp.ch!news.imp.ch!eusc.inter.net!news-fra1.dfn.de!news.rwth-aachen.de!news-out.nuthinbutnews.com!propagator2-sterling!in.nntp.be!gail.ripco.com!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:139699 On Tue, 27 May 2003 23:38:28 GMT, lawrence@c896388-c.attbi.com (Lawrence Statton N1GAK/XE2) wrote: >So, I was thinking as I was walking down the street the other day, >about some of the technologies that have long-gone, and how they might >be entertaining and even educational. > >Towit: How would an engineer go about building a few bits of core >memory today, given that core planes aren't as easy to come by as they >once were. Could just ask to borrow one of my core memory boards :-) But I would probably say no. :-( > >[1]: In my nova-1200 between the switching power supply, and the >magneto-restrictive effects of the core memory, you could "hear" where >in the compile-link-assemble phase the machine was in. All-in-all >very cool. The fans on my nova clone linear PS are so loud you just get an ear ache. Not much fun. -- Arargh at [drop the 'http://www.' from ->] http://www.arargh.com Basic Compiler Samples Page: http://www.arargh.com/basic/basic.html To reply by email, change the domain name, and remove the garbage. ###### Message-ID: <3ED40030.B1CB768@yahoo.com> From: CBFalconer Reply-To: cbfalconer@worldnet.att.net Organization: Ched Research X-Mailer: Mozilla 4.75 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Core Memory Demonstration Project References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 51 Date: Wed, 28 May 2003 00:21:28 GMT NNTP-Posting-Host: 12.90.171.156 X-Complaints-To: abuse@worldnet.att.net X-Trace: bgtnsc04-news.ops.worldnet.att.net 1054081288 12.90.171.156 (Wed, 28 May 2003 00:21:28 GMT) NNTP-Posting-Date: Wed, 28 May 2003 00:21:28 GMT Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!out.nntp.be!propagator2-sterling!news-in.nuthinbutnews.com!cyclone1.gnilink.net!wn12feed!worldnet.att.net!bgtnsc04-news.ops.worldnet.att.net.POSTED!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:139766 Lawrence Statton N1GAK/XE2 wrote: > > So, I was thinking as I was walking down the street the other day, > about some of the technologies that have long-gone, and how they might > be entertaining and even educational. > > Towit: How would an engineer go about building a few bits of core > memory today, given that core planes aren't as easy to come by as they > once were. > > I know that Amidon makes a wide variety of ferrite cores and beads for > the choke market, so they would probably be a good place to start. > > The question is: What are the critical variables for the magnetics > (not even CLOSE to my strong suit), and is there any overlap in the > product lines? > > I think a demonstration circuit of sixteen bits (4 x 4) of > honest-to-god core memory would be a great tool for discussion about > the progression of computer technology. And it has the great > advantage of having a physical artifact for each bit of memory, yet is > entirely solid-state (ignoring any spurious magneto-restrictive > characteristic of the cores [1]). The critical thing is the hysteresis curve, and reasonable matching between individual cores. We used to run a thing called a schmoo plot to check limits. For demo purposes you might as well make a N x 1 system. Then you only need 3 wires, x and y drive, and sense. You can eliminate the inhibit line. Best to shape the x and y drive pulses in trapezoids, with linear rise/fall times. Remember that the pulses are current, not voltage. The basic read/restore sequence for an x 1 system is: reset the bit sense pulse? bit = 1 : bit = 0; if bit = 1 reverse currents and set the bit. out of which cycle you can build counters of as many bits as are available by modifying the last statement above. The delay between applying the drive currents and seeing a sense pulse will give you a clue to the speeds available. -- Chuck F (cbfalconer@yahoo.com) (cbfalconer@worldnet.att.net) Available for consulting/temporary embedded and systems. USE worldnet address! ###### From: ace join_to ware@iinet.net.au (Tony Epton) Newsgroups: alt.folklore.computers Subject: Re: Core Memory Demonstration Project Date: Wed, 28 May 2003 01:29:46 GMT Organization: Aceware Programming Pty Ltd Message-ID: <3ed41090.1873679@news.m.iinet.net.au> References: X-Newsreader: Forte Free Agent 1.1/32.230 Lines: 12 NNTP-Posting-Host: 203.59.54.231 X-Trace: news.iinet.net.au 1054086475 2009 203.59.54.231 Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!enews.sgi.com!logbridge.uoregon.edu!HSNX.atgi.net!newsfeed.iinet.net.au!newsfeed.iinet.net.au!news.iinet.net.au!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:139424 >The question is: What are the critical variables for the magnetics >(not even CLOSE to my strong suit), and is there any overlap in the >product lines? Been wondering the same thing in regards to reinventing some of the magnetic coil logic (pulse logic) in the PDP6 system modules (fantasy dream - will never happen, etc) Tony Epton My counsellor told me I must learn to live in the present. Well I'm halfway there - I can't remember what I did yesterday. ###### Message-ID: <3ED58854.40A4F43A@ev1.net> From: Charles Richmond Reply-To: richmond@ev1.net Organization: Canine Computer Center X-Mailer: Mozilla 4.7C-CCK-MCD {C-UDP; EBM-APPLE} (Macintosh; I; PPC) X-Accept-Language: en MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Core Memory Demonstration Project References: <3ED40030.B1CB768@yahoo.com> <3ED40D1F.8C251CB6@yahoo.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 24 NNTP-Posting-Host: 12.241.15.59 X-Complaints-To: abuse@attbi.com X-Trace: rwcrnsc53 1054174425 12.241.15.59 (Thu, 29 May 2003 02:13:45 GMT) NNTP-Posting-Date: Thu, 29 May 2003 02:13:45 GMT Date: Thu, 29 May 2003 02:13:45 GMT Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!out.nntp.be!propagator2-sterling!news-in.nuthinbutnews.com!cyclone1.gnilink.net!wn14feed!wn13feed!wn12feed!worldnet.att.net!204.127.198.203!attbi_feed3!attbi.com!rwcrnsc53.POSTED!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:139697 Peter Flass wrote: > > CBFalconer wrote: > > > Towit: How would an engineer go about building a few bits of core > > > memory today, given that core planes aren't as easy to come by as they > > > once were. > > _Computerworld_ had one of their "background" articles not too long ago > on a "new" technology that effectively re-creates core memory on a chip > by depositing a few atoms of magnetic material on a matrix of > signal/readout lines. Otherwise, the original core planes were > hand-wired, but I don't know what circuitry would be required to drive > them. > It's called MRAM (magnetoresistive RAM), and "Wired" had an article on it here: -- +----------------------------------------------------------------+ | Charles and Francis Richmond richmond at plano dot net | +----------------------------------------------------------------+ ###### From: john_bailey@rochester.rr.com (John Bailey) Newsgroups: alt.folklore.computers Subject: Re: Core Memory Demonstration Project Message-ID: <3ed5ed79.43260616@news-server.rochester.rr.com> References: X-Newsreader: Forte Free Agent 1.11/32.235 Lines: 26 Date: Thu, 29 May 2003 11:31:19 GMT NNTP-Posting-Host: 66.67.142.181 X-Complaints-To: abuse@rr.com X-Trace: twister.nyroc.rr.com 1054207879 66.67.142.181 (Thu, 29 May 2003 07:31:19 EDT) NNTP-Posting-Date: Thu, 29 May 2003 07:31:19 EDT Organization: Road Runner Path: chonsp.franklin.ch!pfaff.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!enews.sgi.com!news-out.spamkiller.net!propagator2-maxim!news-in.superfeed.net!news-west.rr.com!news-east.rr.com!cyclone.nyroc.rr.com!cyclone-out.nyroc.rr.com!twister.nyroc.rr.com.POSTED!53ab2750!not-for-mail Xref: chonsp.franklin.ch alt.folklore.computers:139772 On Tue, 27 May 2003 23:38:28 GMT, lawrence@c896388-c.attbi.com (Lawrence Statton N1GAK/XE2) wrote: >I think a demonstration circuit of sixteen bits (4 x 4) of >honest-to-god core memory would be a great tool for discussion about >the progression of computer technology. And it has the great >advantage of having a physical artifact for each bit of memory, yet is >entirely solid-state (ignoring any spurious magneto-restrictive >characteristic of the cores [1]). My Moore School Master's thesis was titled: Design of a Magnetic Core Plane Microcomputer Matrix for [Programmable] Pattern Recognition. (1959) The core concept (pun intended) was that a string of cores could be selectively pulsed, resulting in a programmable NOR/NAND gate effect. I am hoping to eventually demonstrate that this concept can be reapplied to the implementation of a Matrix of quantum dots as a programmable quantum computer. If you get serious and want a copy, I'll have to scan it for you. John Bailey http://home.rochester.rr.com/jbxroads/mailto.html