From news.columbia.edu!rpi!usenet.coe.montana.edu!caen!uwm.edu!ux1.cso.uiuc.edu!news.iastate.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!news Fri Oct 2 18:36:04 EDT 1992 Article: 15 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!rpi!usenet.coe.montana.edu!caen!uwm.edu!ux1.cso.uiuc.edu!news.iastate.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!news From: jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) Subject: FAQ Sender: news@news.uiowa.edu (News) Message-ID: <1992Oct2.175013.25097@news.uiowa.edu> Date: Fri, 2 Oct 1992 17:50:13 GMT Nntp-Posting-Host: pyrite.cs.uiowa.edu Organization: University of Iowa, Iowa City, IA, USA Lines: 281 This is a trial posting of a FAQ for this newsgroup. I'd appreciate any and all comments I can get. In particular, I'd like to get the original list price for a minimum configuration of each make and model of the -8, the sales volume for each, and the accurate end-points for the production run for each. ================= begin trial posting of FAQ ================== Frequently Asked Questions about the PDP-8 By Douglas Jones, jones@cs.uiowa.edu What is a PDP? For over a decade, all programmable digital computers sold by Digital Equipment Corporation were sold as Programmable Data Processors (PDPs) instead of computers. I have DEC documentation that actually calls them "PDPs", so this is not improper usage. The name was chosen because the first DEC computer, the PDP-1, had a selling price of $120,000 when competing machines were selling for over $1,000,000. Everyone knew that computers were big and expensive and needed a computer center and a large staff, and DEC was trying to sell something relatively inexpensive that didn't need such support facilities. DEC chose to deal with these steriotypes by avoiding the term "computer" entirely in their sales efforts. DEC built a number of different computers under the PDP label, of which the PDP-8 family machines were the smallest and least expensive. The PDP-10, for example, was a large machine worthy of a computer center and large support staff. The PDP-14 wasn't even a computer -- it was a ROM based industrial controller. The PDP-11, a 16 bit minicomputer/microprocessor family, is the only DEC product still being sold under the PDP name. What is a PDP-8? The PDP-8 family of minicomputers were built by Digital Equipment corporation between 1965 and 1990. These machines were characterized by a 12 bit word, with no hardware byte structure, a 4K minimum memory configuration, and an extremely simple instruction set. By 1970, the PDP-8 was the best selling computer in the world, and many models of the PDP-8 set new records as the least expensive computer on the market. The PDP-8 has been described as the model-T of the computer industry. Gordon Bell (who later was chief architect of the PDP-11 and who, as Vice President, oversaw the development of the VAX) says that the instruction set of the PDP-8 was not really original with him. He credits Seymour Cray (of CDC and later Cray) with the original idea. Cray's CDC 160 family, sold starting around 1959, was a very similar 12 bit minicomputer, and the peripheral processors of Cray's first supercomputer, the CDC 6600, also look very familiar to PDP-8 programmers. The following basic models of the PDP-8 were sold by DEC: MODEL DATES SALES COST TECHNOLOGY COMPATABILITY PDP-5 63-65 Transistor Limited PDP-8 65-68 >1000 <$100K Transistor Full LINC-8 66? >500? <$100K Transistor Full (1) PDP-8/S 67? >1000? <$10K Transistor Limited and slow! PDP-8/I 68? >2000? <$100K TTL Full PDP-8/L 68? >2000? <$100K TTL Full (2) PDP-12 69? >1000? <$100K TTL Full (3) PDP-8/E 70-78 >10K <$10K TTL MSI Omnibus Full (4) PDP-8/F 73-78? >10K? <$10K TTL MSI Omnibus Full (uses 8/E CPU) PDP-8/M 73-78? >10K? <$10K TTL MSI Omnibus Full (an OEM 8/F) PDP-8/A 75-84? >10K? <$10K TTL LSI Omnibus Full (new CPU) (5) VT78 78-80 > ? Microprocessor Full (Intersil IM6100) Dm I (6)80-84 Microprocessor Full (Intersil IM6120) Dm II Microprocessor Full Dm III 84-90 Microprocessor Limited expansion Dm III+ 8?-90 Microprocessor Limited expansion (7) Notes (1) The LINC-8 combined a modified PDP-8 with extenstions supporting compatibility with the Laboratory Instrumentation Control Computer developed at Lincoln Labs in the early 1960s. (2) The PDP-8/L was intended as a scaled down version of the PDP-8/I, and most of them had only 4K memory, but eventually, a full range of upgrade options were sold. (3) The PDP-12 was originally designated the LINC-8/I; it was a follow-on to the LINC-8. It had the most impressive control panel of any 8-family machine. (4) The PDP-8/E is considered by many to be the definitive model of the PDP-8. (5) After 1978, Reuters bought almost all of the remaining PDP-8/A production run (5-6 years at 1000/month). (6) Dm stands for DECmate. (7) The total sales figure for the PDP-8 family is estimated at over 300,000 machines. Over 8500 of these were sold prior to 1970. The above list does not include many PDP-8 variants sold by DEC to meet the needs of various special users. For example, the Industrial-8 was really just a PDP-8/E with a different nameplate and color scheme. In addition, DEC made many peripheral controllers for the PDP-11 and PDP-15 that used IM6100 microprocessors. The following PDP-8 compatable or semi-compatable machines were made and sold by others; very little is known about many of these: MODEL DATE MAKER, NOTES MP-12 6? Fabritek DCC-112 6? Digital Computer Controls DCC-112H 6? Digital Computer Controls TPA 68? Hungarian, possibly a DEC PDP-8/L in drag 6100 Sampler 7? Intersil, their promotional kit Intercept 7? Intersil Intercept Jr 7? Intersil SBC-8 84-88 CESI, Based on IM6120, SCSI bus Where can I get a PDP-8 today? The CESI machine may still be on the market, for a high price, but generally, you can't buy a new PDP-8 anymore. There are quite a few PDP-8 machines to be found in odd places on the used equipment market. They were widely incorporated into products such as computer controlled machine tools, X-ray diffraction machines, and other industrial and lab equipment. Many of them were sold under the EduSystem marketing program to public schools and universities, and others were used to control laboratory instrumentation. Reuters bought the tail end of the production run. If you can't get real hardware, you can get emulators. Over the years, many PDP-8 emulators have been written; the best of these are indistinguishable from the real machine from a software prespective, and on a modern high-speed RISC platform, these frequently outperform the hardware they are emulating. Where can I get PDP-8 documentation? The 1973 Introduction to Programming was probably DEC's definitive manual for this family, but it is out of print, and DEC was in the habit of printing much of their documentation on newsprint with paperback bindings, which is to say, surviving copies tend to be yellow and brittle. DEC distributed huge numbers of catalogs and programming handbooks in this inexpensive paperback format, and these circulate widely on the second-hand market. Whe research laboratories and electronics shops are being cleaned out, it is still common to find a few dusty, yellowed copies of these books being thrown in the trash. Maintenance manuals are harder to find, but more valuable. Generally, you'll need to find someone who's willing to photocopy one of the few surviving copies. Fortunately, DEC has been friendly to collectors, granting fairly broad letters of permission to reprint obsolete documentation, and the network makes if fairly easy to find someone who has the documentation you need and can get copies. What operating systems were written for the PDP-8? A punched paper-tape library of stand-alone programs was commonly used with the smallest (diskless and tapeless) configurations from the beginning up through the late 1970's. Many paper tapes from this library survive to the present at various sites! The DECtape Library System was an early DECtape oriented save and restore system that allowed a reel of tape to hold a directory of named files that could be loaded and run. Eventually, this supported a tape-to-tape text editor and it could be used for on-line program development. The 4K Disk Monitor System provided similar facilities using disks or DECtape. This supported on-line program development and it with any device that supported 129 word block sizes. MS/8 or the R-L Monitor System, developed starting in 1966 and submitted to DECUS in 1970. P?S/8, developed starting in 1971 from an MS/8 foundation. Runs on minimal PDP-8 configurations, supports device semi-independant I/O and a file system on a random-access device, including DECtape. OS/8, developed in parallel with P?S/8, became the main PDP-8 programming environment sold by DEC. The minimum configuration required was 8K words and a random-access device to hold the system. TSS/8 was developed in 1968 as a timesharing system. It required a minimum of 12K words of memory and a swapping device. It was fairly widely sold to support educational timesharing. Other timesharing systems developed for the PDP-8 include MULTI-8, ETOS, and OMNI-8; these were similar to TSS/8, and by the mid 1970's, many of these were true virtual machine operating systems in the same spirit as IBM's VM-370. WPS was DEC's word processing system that was widely used on the 1980's vintage machines with a special WPS keyboard replacing the standard keyboard. What programming languages were supported on the PDP-8 The PAL family of assembly languages were as close to a standard assembly language as can be found for the PDP-8. These produced absolute object code and versions of PAL would run on minimally configured machines. MACRO-8 was DEC's first macro assembly language for the PDP-8, but it was never used outside the paper-tape environment. MACREL and SABR were assembly languages that produced relocatable output; these were developed to support different FORTRAN compilers. SABR was used as a final pass for DEC's FORTRAN compilers. A subset of FORTRAN was supported on both the PDP-5 and the original PDP-8. Surviving documentation describes a DEC compiler from 1964 and a compiler written by Information Control Systems from 1968. RTPS FORTRAN contained real-time extensions and was a full FORTRAN IV (ANSI FORTRAN 66) implementation. Some later DEC documentation refers to 4K FORTRAN and 8K FORTRAN; the former is the old subset compiler, the latter is a reference to the code descended from RTPS FORTRAN. FOCAL, an interpretive language comparable to BASIC was available on all models of the family, including the PDP-5 and PDP-8/S. BASIC was also available, and was widely used on PDP-8 systems sold under the EduSystem marketing program. A version was available that ran in 4K, and there was an 8K time-sharing version. Algol was available from a fairly early date. At least two Pascal compilers were developed for the PDP-8. At least two LISP interpreters were written for the PDP-8; one runs in 4K, the other can use up to 16K. TECO, the text editor, is available, and is also a general purpose language, and someone is working on a PDP-8 C. Where can I get PDP-8 software? DECUS, the DEC User Society, is still alive and well, and their submission form still lists PAL-8 and FOCAL as languages in which they accept submissions! There is a young but growing FTPable archive of PDP-8 software at ftp.telebit.com in directory /pub/pdp8. Where can I get additional information? The file WHAT-IS-A-PDP8, by Charles Lasner contains considerable additional information; this file is included in the FTPable archive cited above. This file gives details of every model of the PDP-8, including the small quirks and incompatabilities that (to be generous) allow software to determine which model it is running on. These quirks also make it all too easy for careless programmers to write almost portable software with very obscure bugs. The mailing list pdp8-lovers@ai.mit.edu reaches a number of PDP-8 owners and users, not all of whom have USENET feeds. The USENET newsgroup alt.sys.pdp8 is fairly new, but someday, the newsgroup and mailing list will be gatewayed to each other. Many "archival" books have included fairly complete descriptions of the PDP-8; among them, "Computer Architecture, Readings and Examples" by Gordon Bell and Allen Newell is among the most complete (and difficult to read). Considering Bell's role in the design of the PDP-8 and the history of DEC, the description in this book should be accurate! From news.columbia.edu!sol.ctr.columbia.edu!spool.mu.edu!decwrl!csus.edu!netcom.com!rbp Fri Oct 2 20:31:55 EDT 1992 Article: 16 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!sol.ctr.columbia.edu!spool.mu.edu!decwrl!csus.edu!netcom.com!rbp From: rbp@netcom.com (Bob Pasker) Subject: Re: FAQ Message-ID: <1992Oct2.232759.21488@netcom.com> Organization: Netcom - Online Communication Services (408 241-9760 guest) References: <1992Oct2.175013.25097@news.uiowa.edu> Date: Fri, 2 Oct 1992 23:27:59 GMT Lines: 18 jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) writes: > and DEC was trying to sell something relatively inexpensive that > didn't need such support facilities. DEC chose to deal with these > steriotypes by avoiding the term "computer" entirely in their > sales efforts. one nit to pick: olson et al chose not to call their machines "computers" because the investors would have then refused to buy in. ostensibly, they felt that the cmputer field would be less lucrative than makeing modules, like the "flip-chip." could be urban legend, could be truth, but its at least plausible. someone call ken and ask him. -- --- bob pasker ---- rbp@netcom.com From news.columbia.edu!watsun.cc.columbia.edu!lasner Mon Oct 5 04:39:23 EDT 1992 Article: 17 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!watsun.cc.columbia.edu!lasner From: lasner@watsun.cc.columbia.edu (Charles Lasner) Subject: Re: Flip-Chips (was Re: FAQ) Message-ID: <1992Oct5.075414.18772@news.columbia.edu> Sender: usenet@news.columbia.edu (The Network News) Nntp-Posting-Host: watsun.cc.columbia.edu Reply-To: lasner@watsun.cc.columbia.edu (Charles Lasner) Organization: Columbia University References: <1992Oct2.175013.25097@news.uiowa.edu> <1992Oct2.232759.21488@netcom.com> Date: Mon, 5 Oct 1992 07:54:14 GMT In article <1992Oct2.232759.21488@netcom.com> rbp@netcom.com (Bob Pasker) writes: > >one nit to pick: olson et al chose not to call their machines >"computers" because the investors would have then refused to buy in. >ostensibly, they felt that the cmputer field would be less lucrative >than makeing modules, like the "flip-chip." could be urban legend, >could be truth, but its at least plausible. someone call ken and >ask him. The notion about PDP's versus computers sounds plausible, but does anyone have any info about it? In any case, the Flip-Chip notion is a legend in itself. For some reason, undue emphasis is given to a detail of the implementation of some module series, mostly R-series, but S and probably B as well *might* have this. Flip-Chips are the small hybrid packages that are sometimes used on some of the cards which are used in the early models of PDP-8, -10, -9, LINC-8, etc. in these three main module series. They are *never* a requirement for most modules. If you pickup a random R-series module, it has transistors and diodes and resistors and capacitors on it, no Flip-Chips at all. Some of the cards do substitute a little thick-film hybrid package for some of the diodes, resistors and capacitors, essentially the components that make up the so-called DCD gate commonly used in the logic. The purpose is to standardize the signals between cards, and is essentially a way to get a level and/or a pulse as input to a flip-flop or gate. Today we would just have edge and level-triggered flip-flops where necessary. In any case, some of the leads of the DCD gate are component interconnect, so it can be looked upon as a module. DEC eventually did make Flip-Chip modules, so on certain cards, you find these little packages in lieu of the standard set of components which doesn't dramatically cut down on either parts count or even lead count. In fact, many of the Flip-Chips have proven to be unreliable and have to be replaced with the normal complement of discrete components when repairing the module. All of them are readily available: silver-mica capacitors, 1/4 Watt resistors and miniature silicon diodes are all that constitutes what's in a Flip-Chip. Eventually, some "evil" modules appeared. They usually have numbers like R107 s1a where the s1a means that someone bothered to relayout the module so it can *only* take Flip-Chips :-(. (As opposed to the earlier design which could take either the loose components or the same exact parts count as the newer ones. The only difference from a manufacturing standpoint is the arbitrarily different etch and a modestly smaller drilled-hole count. Hardly worth offseting the cost of the redesign.) For these modules, repair is more difficult. In an pinch, the components can be soldered together to make a Flip-Chip "equivalent" and then the whole bunch is inserted into the Flip-Chip's solder holes. Alternatively, a working earlier card gets "cannabalized" for Flip-Chips to fix the Flip-Chip-only card. The earlier design is then refitted with the loose components it is designed to take. When done, you have a working newer s1a card, and an older card returned to older-still standards. So, descriptions of clean rooms, etc. aside, Flip-Chips per se play a secondary role in the production of modules sometimes described as "Flip-Chip modules" which may be 100% devoid of Flip-Chips. Moreover, some modules such as R001 and R002 which only contain diodes, never have Flip-Chips. Can anyone post the suffix variation for some of these cards that indicate that the card also lacks the diodes? (Yes, I saw one of these once. It wasn't s1a, but some other suffix meaning all components deleted!) To my knowledge, there isn't a single R, S, or B-series module which *only* came in Flip-Chip-bearing variety. Moreover, Flip-Chips only came in a few standard configurations, since they only replaced certain component sets, thus cards tended to have some discrete components anyway. And they *never* replace the discrete transistors used on the module. cjl (in possession if literally thousands of R-series modules) From news.columbia.edu!rpi!usc!sol.ctr.columbia.edu!destroyer!uunet!news.uiowa.edu!news Mon Oct 5 14:07:44 EDT 1992 Article: 18 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!rpi!usc!sol.ctr.columbia.edu!destroyer!uunet!news.uiowa.edu!news From: jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) Subject: Re: Flip-Chips (was Re: FAQ) Sender: news@news.uiowa.edu (News) Message-ID: <1992Oct5.134702.7667@news.uiowa.edu> Date: Mon, 5 Oct 1992 13:47:02 GMT References: <1992Oct5.075414.18772@news.columbia.edu> Nntp-Posting-Host: pyrite.cs.uiowa.edu Organization: University of Iowa, Iowa City, IA, USA Lines: 28 >From article <1992Oct5.075414.18772@news.columbia.edu>, by lasner@watsun.cc.columbia.edu (Charles Lasner): > > In any case, the Flip-Chip notion is a legend in itself. For some reason, > undue emphasis is given to a detail of the implementation of some module > series, mostly R-series, but S and probably B as well *might* have this. There's another side to this legend, though. Originally, in the 1965 era, the word flip-chip was a reference to the hybrid integrated circuits DEC was trying to use. By the end of the decade, though, DEC was assertively referring to the logic modules themselves as flip chips. Thus, every M series logic module I've got seems to say FLIP CHIP across the top of the module right under the handle (except the M211, which says DEC FLIP CHIP). It seems clear that by 1970, DEC wanted people to call the modules themselves flip chips. On another topic, IBM, with the introduction of the IBM System 360 in 1965, declared the birth of the third generation of computers. (The number 360 was a marketing ploy in itself, standing for "a third generation machine for the 1960's"; that's why they had to renumber to 370 when the new decade came.) IBM said that third generation machines were characterized by integrated circuits, but the System 360 only had hybrid integrated circuits, not monolithic circuits. By this standard, the Classic PDP-8 could be called a third generation machine! Doug Jones jones@cs.uiowa.edu From news.columbia.edu!rpi!batcomputer!theory.TC.Cornell.EDU!mdw Mon Oct 5 14:23:52 EDT 1992 Article: 19 of alt.sys.pdp8 Xref: news.columbia.edu alt.sys.pdp8:19 alt.folklore.computers:32188 misc.forsale.computers:54508 Newsgroups: alt.sys.pdp8,alt.folklore.computers,misc.forsale.computers Path: news.columbia.edu!rpi!batcomputer!theory.TC.Cornell.EDU!mdw From: mdw@theory.TC.Cornell.EDU (Matt Welsh) Subject: Wanted: Unused PDP-8? Message-ID: <1992Oct5.170334.12874@tc.cornell.edu> Sender: news@tc.cornell.edu Nntp-Posting-Host: theory.tc.cornell.edu Organization: Cornell Theory Center Date: Mon, 5 Oct 1992 17:03:34 GMT I know this sounds crazy, but I'm wondering if someone out there has an unwanted/unloved machine in the PDP-8 line that they'd like to give a happy home (namely, to me), or sell. There must be one out there, somewhere, sitting in someone's machine room or attic, collecting dust-- if so, send me email and I'll see what I can do about getting it off of your hands. :) The actual model probably isn't important-- I'm just looking for one of these machines to bang around on for a while. Thanks for any help. mdw -- Matt Welsh mdw@tc.cornell.edu +1 607 253 2737 Systems Programmer, Cornell Theory Center "Yow! Up ahead! It's a DONUT HUT!!" From news.columbia.edu!watsun.cc.columbia.edu!lasner Mon Oct 5 19:43:35 EDT 1992 Article: 20 of alt.sys.pdp8 Xref: news.columbia.edu alt.sys.pdp8:20 alt.folklore.computers:32191 Newsgroups: alt.sys.pdp8,alt.folklore.computers Path: news.columbia.edu!watsun.cc.columbia.edu!lasner From: lasner@watsun.cc.columbia.edu (Charles Lasner) Subject: Re: Flip-Chips (was Re: FAQ) Message-ID: <1992Oct5.182237.27062@news.columbia.edu> Sender: usenet@news.columbia.edu (The Network News) Nntp-Posting-Host: watsun.cc.columbia.edu Reply-To: lasner@watsun.cc.columbia.edu (Charles Lasner) Organization: Columbia University References: <1992Oct5.075414.18772@news.columbia.edu> <1992Oct5.134702.7667@news.uiowa.edu> Date: Mon, 5 Oct 1992 18:22:37 GMT In article <1992Oct5.134702.7667@news.uiowa.edu> jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) writes: > >There's another side to this legend, though. Originally, in the 1965 era, >the word flip-chip was a reference to the hybrid integrated circuits DEC >was trying to use. By the end of the decade, though, DEC was assertively >referring to the logic modules themselves as flip chips. Thus, every M >series logic module I've got seems to say FLIP CHIP across the top of the >module right under the handle (except the M211, which says DEC FLIP CHIP). >It seems clear that by 1970, DEC wanted people to call the modules >themselves flip chips. Absolutely. DEC exaggerated the importance of the original Flip-Chips to the point that they had to support the name for virtually the entire product line of modules, whether Flip-Chips were part of the construction or not. But if you look at the early literature, such as the somewhat hyped pictures in the early Logic Handbooks, etc., it's clear that they are intending to focus in on DEC's "high-tech" production capabilities of Flip-Chips, and to take the focus away from the ordinary techniques that DEC, as a module maker, used to produce modules no better or worse than a dozen other module houses. This is likely a carry-over from an earlier era when DEC wasn't a computer maker but rather a module-only house for other companies. Can anyone cite a specific machine from another company that was actually made out of DEC modules but wasn't "heralded" as such (Circa 1957-1961 in all probability). BTW, I have a relatively rare publication about Flip-Chips. Before them, DEC made only Systems Modules, which are much larger and always using discrete components. They are characterized by aluminum frame strips, larger connectors and all-digit module numbers. The handbook that describes them is an 8.5 x 11" book of overall higher quality than most later DEC paper-backs such as the Logic Handbooks. There was a singular "transition" publication which is essentially the precursor to the entire family of Logic Handbooks that discusses Flip-Chip modules; it's a 1964 Flip-Chip Handbook and is of the same quality. Because the paper quality is so much better, it has not yellowed and the thick paper stock binding hasn't broken. The one year or more newer Logic Handbooks have all since deteriorated severely :-(. cjl From news.columbia.edu!watsun.cc.columbia.edu!lasner Mon Oct 5 19:44:22 EDT 1992 Article: 21 of alt.sys.pdp8 Xref: news.columbia.edu alt.sys.pdp8:21 alt.folklore.computers:32199 misc.forsale.computers:54557 Newsgroups: alt.sys.pdp8,alt.folklore.computers,misc.forsale.computers Path: news.columbia.edu!watsun.cc.columbia.edu!lasner From: lasner@watsun.cc.columbia.edu (Charles Lasner) Subject: Re: Wanted: Unused PDP-8? Message-ID: <1992Oct5.234213.4863@news.columbia.edu> Sender: usenet@news.columbia.edu (The Network News) Nntp-Posting-Host: watsun.cc.columbia.edu Reply-To: lasner@watsun.cc.columbia.edu (Charles Lasner) Organization: Columbia University References: <1992Oct5.170334.12874@tc.cornell.edu> Date: Mon, 5 Oct 1992 23:42:13 GMT In article <1992Oct5.170334.12874@tc.cornell.edu> mdw@theory.TC.Cornell.EDU (Matt Welsh) writes: >I know this sounds crazy, but I'm wondering if someone out there >has an unwanted/unloved machine in the PDP-8 line that they'd like >to give a happy home (namely, to me), or sell. There must be one >out there, somewhere, sitting in someone's machine room or attic, >collecting dust-- if so, send me email and I'll see what I can do >about getting it off of your hands. :) The actual model probably >isn't important-- I'm just looking for one of these machines to >bang around on for a while. > >Thanks for any help. > >mdw > >-- >Matt Welsh mdw@tc.cornell.edu +1 607 253 2737 >Systems Programmer, Cornell Theory Center > "Yow! Up ahead! It's a DONUT HUT!!" For any "serious" PDP-8 enthusiast, there is quite a lot of help out there, and many people with long-term commitments to the architecture, which is still actively being developed today by hobbyists, and a smattering of still existing applications, etc. If Matt's request is a valid one, there is more than enough help available. However, a common characteristic of the group of -8 enthusiasts is: please only ask assistance if you have some expectations of commitment yourself. Idle curiosity is not welcome if effort is to be spent. Idle curiousity per se is not unwelcome, however it is directed to various FAQ documents (some of which are being prepared currently). Some of these are available via anonymous FTP from ftp.telebit.com in the /pub/pdp8 area. If after availing one's self of all of the relevant info, and you still want to acquire enough of a machine to be useful towards some endeavor, even if it's nothing more than studying the architecture, then requests such as this are welcome. However, if the request is really just an attempt to get the ability to program the architecture on some basis, and not to get a hands-on experience with the machine, the use of a simulator is recommended. There are several CPU-only simulators available, and some with varying levels of peripheral support. There are two ongoing projects (for PC's and MAC's) that when available will be capable of running PDP-8 systems software from media that can also boot up on suitably configured *real* PDP-8's. This means that there is direct media interchange between the simulated machine and the real machine. Real machines in turn, if suitably configured can exchange media between other real machines and other simulators. (The PC-based simulator runs with media impossible to read on the MAC version, etc.) There is an additional problem peculiar to PDP-8's and to a lesser extent PDP-11's. Since the machines are modular, a PDP-8 is what some people believe they are discussing, when in fact they are merely talking about a CPU and memory and a buss without any peripherals. Some of these machines were even sold sans peripherals as they were imbedded in some OEM systems with custom peripherals designed by the OEM, not DEC. For example, thousands of PDP-8/M machines were once used by Burger King as point-of-sale terminal systems. Each machine supported 1-3 special-purpose terminals made by AMF for Burger King, and a special communications port used for central warehouse inventory control after hours, etc. If any of these machines have become available to the used market, clearly the Burger King cards are of little use to anyone else. These machines even lack a normal device 03/04 console interface, yet to the uninitiated, these are PDP-8's as opposed to PDP-8 CPU-and-memory-only. The usual definition of a PDP-8 as it applies to this group is a machine with a minimal configuration or better, which is capable of running the existing software. Clearly a machine such as described above is less than that. In fact, a simulator is a far better machine in most ways. However, any CPU can, with serious effort applied, be turned into a "real" machine by adding suitable peripherals. This can take the form of actual terminals and other interfaces to other devices, or can be interfaces to other support machines. For example, a PDP-8/e with 12K and two serial ports can be used with a PC or other machine, assuming a custom support program is written on both ends. The expertise to do this is available in the community of PDP-8 enthusiasts in case anyone is interested. All that's required is that a program be written that supports any form of "glass TTY:" relative to the I/O associated with one of the serial ports, i.e., it is a terminal emulator, preferably in the VT-100 family, and also supports block transfers via the other port. The baud rate of the block device support can be made fairly high to allow a decent rate of performance, such as 38,400 baud or more. OS/8 can be implemented in this little hardware, and P?S/8 can be implemented in as little as 8K. (Configurations above 4K require extended memory control module as well as the other memory, which comes in 4K, 8K, 16K and 32K boards from various vendors, etc.) The serial port can be eliminated and replaced with a parallel port if the serving machine can do bi-directional parallel transfers. (There has been some discussion about possibly modifying a PC standard parallel card to allow this; PS/2 models allegedly already support this.) This would allow an even faster block device, etc. If an additional serial port is added to the 8/e, the system can also support Kermit-12, etc. If an RX01 or 02 and RX8E is added, then the serving machine can be eliminated, although it is apparent that the serving machine may offer a better overall device to the 8/e than does the limited RX01/02, but the alternative is for older clunkier peripherals, since most of the PDP-8/e's haven't benefited from peripheral technology improvement available on virtually every machine today. This isn't a reflection on the -8 whatsoever, just that you have to have new interfaces to talk to new technology, etc. Thus, unless you are committed to supporting a large, heavy, hot, finicky older disk, or use a low-performance small capacity disk like an RX, an all-original PDP-8's peripherals may do you in. This is why some people are suggesting embedded systems such as 80186 minimal machines that control IDE disks with interfaces to the -8/e or something along those lines. My own 8/e-8/a has a 6809-based controller that talks to an SCSI buss and peripherals using a DMA channel to the -8. Using this kind of solution allows for a high-performance low-cost peripheral, and allows the entire machine other than the terminal to be inside the table-top case of the basic PDP-8/e. As for the terminal, almost anything will work; my novel solution to this problem is that I (occasionally) use a DECmate III running Kermit-12 as the console terminal of my 8/e system :-). The fledgling PDP-8 archive on ftp.telebit.com will grow and allow free access to much PDP-8 software to allow anyone to view typical code that runs on the machine, and to allow anyone with the basics to enhance their own library, etc. Anyone who wishes assistance in this sort of thing is invited to post to the pdp8-lover's mailing list: pdp8-lovers@ai.mit.edu. Send e-mail to pdp8-lovers-request@ai.mit.edu to subscribe, etc. cjl From news.columbia.edu!rpi!usc!sol.ctr.columbia.edu!spool.mu.edu!umn.edu!csus.edu!netcom.com!rbp Tue Oct 6 00:17:13 EDT 1992 Article: 22 of alt.sys.pdp8 Xref: news.columbia.edu alt.sys.pdp8:22 alt.folklore.computers:32204 Newsgroups: alt.sys.pdp8,alt.folklore.computers Path: news.columbia.edu!rpi!usc!sol.ctr.columbia.edu!spool.mu.edu!umn.edu!csus.edu!netcom.com!rbp From: rbp@netcom.com (Bob Pasker) Subject: Re: Flip-Chips (was Re: FAQ) Message-ID: <1992Oct6.032316.7924@netcom.com> Organization: Netcom - Online Communication Services (408 241-9760 guest) References: <1992Oct5.075414.18772@news.columbia.edu> <1992Oct5.134702.7667@news.uiowa.edu> <1992Oct5.182237.27062@news.columbia.edu> Date: Tue, 6 Oct 1992 03:23:16 GMT Lines: 11 lasner@watsun.cc.columbia.edu (Charles Lasner) writes: >Logic Handbooks. There was a singular "transition" publication which is >essentially the precursor to the entire family of Logic Handbooks that >discusses Flip-Chip modules; it's a 1964 Flip-Chip Handbook and is of the >same quality. Because the paper quality is so much better, it has not yellowed >and the thick paper stock binding hasn't broken. The one year or more newer >Logic Handbooks have all since deteriorated severely :-(. -- --- bob pasker ---- rbp@netcom.com From news.columbia.edu!sol.ctr.columbia.edu!spool.mu.edu!agate!garnet.berkeley.edu!tedcrum Tue Oct 6 21:57:55 EDT 1992 Article: 23 of alt.sys.pdp8 Path: news.columbia.edu!sol.ctr.columbia.edu!spool.mu.edu!agate!garnet.berkeley.edu!tedcrum From: tedcrum@garnet.berkeley.edu () Newsgroups: alt.sys.pdp8 Subject: Free Rainbow Date: 6 Oct 1992 07:20:08 GMT Organization: University of California, Berkeley Lines: 8 Distribution: ba Message-ID: <1aren8INNa06@agate.berkeley.edu> NNTP-Posting-Host: garnet.berkeley.edu In reading the initial posting of this group, I note that the Rainbow is grist for the mill. Can anyone help me find a good home for a monochome, floppy disk Rainbow with some software and an LA100 printer? Thanks! Ted (My boss thinks Focal was the best language ever) Crum (510) 642-5301 From news.columbia.edu!sol.ctr.columbia.edu!usc!rpi!batcomputer!munnari.oz.au!metro!seagoon.newcastle.edu.au!jupiter.newcastle.edu.au!c8922369 Tue Oct 6 21:58:12 EDT 1992 Article: 24 of alt.sys.pdp8 Xref: news.columbia.edu alt.sys.pdp8:24 alt.folklore.computers:32214 misc.forsale.computers:54607 Newsgroups: alt.sys.pdp8,alt.folklore.computers,misc.forsale.computers Path: news.columbia.edu!sol.ctr.columbia.edu!usc!rpi!batcomputer!munnari.oz.au!metro!seagoon.newcastle.edu.au!jupiter.newcastle.edu.au!c8922369 From: c8922369@jupiter.newcastle.edu.au (Leon James Garde) Subject: Re: Wanted: Unused PDP-8? Message-ID: Sender: news@seagoon.newcastle.edu.au Organization: Uni of Newcastle, Australia References: <1992Oct5.170334.12874@tc.cornell.edu> Date: Tue, 6 Oct 1992 09:33:13 GMT Lines: 15 mdw@theory.TC.Cornell.EDU (Matt Welsh) writes: >I know this sounds crazy, but I'm wondering if someone out there >has an unwanted/unloved machine in the PDP-8 line that they'd like >to give a happy home (namely, to me), or sell. There must be one What sounded crazier, is that the subject line could have been interpreted as .... wanted: NEVER used pdp-8 ? ask around a few government departments for those, Id say ! leon From news.columbia.edu!sol.ctr.columbia.edu!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!cbnewsc!cbfsb!att-out!cbnewsl!rl Tue Oct 6 23:04:14 EDT 1992 Article: 25 of alt.sys.pdp8 Xref: news.columbia.edu alt.sys.pdp8:25 alt.folklore.computers:32220 misc.forsale.computers:54610 Newsgroups: alt.sys.pdp8,alt.folklore.computers,misc.forsale.computers Path: news.columbia.edu!sol.ctr.columbia.edu!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!cbnewsc!cbfsb!att-out!cbnewsl!rl From: rl@cbnewsl.cb.att.com (roger.h.levy) Subject: Re: Wanted: Unused PDP-8? Organization: AT&T Bell Laboratories Distribution: na Date: Tue, 6 Oct 1992 10:47:38 GMT Message-ID: <1992Oct6.104738.21099@cbnewsl.cb.att.com> Followup-To: poster References: <1992Oct5.170334.12874@tc.cornell.edu> <1992Oct5.234213.4863@news.columbia.edu> Lines: 15 In article <1992Oct5.234213.4863@news.columbia.edu>, lasner@watsun.cc.columbia.edu (Charles Lasner) writes: > In article <1992Oct5.170334.12874@tc.cornell.edu> mdw@theory.TC.Cornell.EDU (Matt Welsh) writes: > >I know this sounds crazy, but I'm wondering if someone out there > >has an unwanted/unloved machine in the PDP-8 line that they'd like > >to give a happy home (namely, to me), or sell. There must be one > >out there, somewhere, sitting in someone's machine room or attic, > > For any "serious" PDP-8 enthusiast, there is quite a lot of help out there, > > ... However, if the request is really just an attempt to get the > ability to program the architecture on some basis, and not to get a hands-on > experience with the machine, the use of a simulator is recommended. I am quite sure that at one time there was a microprocessor that fully emulated the PDP-8. Is there still a supply of these chips? From news.columbia.edu!sol.ctr.columbia.edu!zaphod.mps.ohio-state.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!news Tue Oct 6 23:05:18 EDT 1992 Article: 26 of alt.sys.pdp8 Xref: news.columbia.edu alt.sys.pdp8:26 alt.folklore.computers:32232 Newsgroups: alt.sys.pdp8,alt.folklore.computers Path: news.columbia.edu!sol.ctr.columbia.edu!zaphod.mps.ohio-state.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!news From: jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) Subject: Re: Flip-Chips (was Re: FAQ) Sender: news@news.uiowa.edu (News) Message-ID: <1992Oct6.140816.26967@news.uiowa.edu> Date: Tue, 6 Oct 1992 14:08:16 GMT References: <1992Oct5.182237.27062@news.columbia.edu> Nntp-Posting-Host: pyrite.cs.uiowa.edu Organization: University of Iowa, Iowa City, IA, USA Lines: 22 > But if you look at the early literature, such as the somewhat hyped > pictures in the early Logic Handbooks, etc., it's clear that they are > intending to focus in on DEC's "high-tech" production capabilities of > Flip-Chips, and to take the focus away from the ordinary techniques > that DEC, as a module maker, used to produce modules no better or worse > than a dozen other module houses. Yes. The loose-leaf notebook "Digitial Flip-Chip Modules, First Revision, July 1965, C-105 7/65" is full of such hype. They have nice photos of such things as hand-assembly of hybrid circuit modules -- from a modern semiconductor manufacturing perspective, it's really quite quaint! > BTW, I have a relatively rare publication about Flip-Chips. I think I just cited the second edition of the same publication! It's a pity that DEC didn't stick to this format, because it's refreshing to see old DEC documentation that's not yet yellowed and crumbling! Is there a need for a tutorial on how to rescue old manuals when they reach this state? I've done reprints of one DEC handbook on archival paper, and I'm willing to share the art! Doug Jones jones@cs.uiowa.edu From news.columbia.edu!watsun.cc.columbia.edu!lasner Tue Oct 6 23:05:29 EDT 1992 Article: 27 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!watsun.cc.columbia.edu!lasner From: lasner@watsun.cc.columbia.edu (Charles Lasner) Subject: Re: Wanted: Unused PDP-8? Message-ID: <1992Oct7.030318.7610@news.columbia.edu> Sender: usenet@news.columbia.edu (The Network News) Nntp-Posting-Host: watsun.cc.columbia.edu Reply-To: lasner@watsun.cc.columbia.edu (Charles Lasner) Organization: Columbia University References: <1992Oct5.170334.12874@tc.cornell.edu> <1992Oct5.234213.4863@news.columbia.edu> <1992Oct6.104738.21099@cbnewsl.cb.att.com> Distribution: na Date: Wed, 7 Oct 1992 03:03:18 GMT In article <1992Oct6.104738.21099@cbnewsl.cb.att.com> rl@cbnewsl.cb.att.com (roger.h.levy) writes: > >I am quite sure that at one time there was a microprocessor that fully >emulated the PDP-8. Is there still a supply of these chips? Several people have been asking for these chips. The easiest way to get them is to get a DECmate. The CPU is usually socketed, except for the newest models such as DECmate III and III+. The 6100 is a compatible PDP-8 CPU-on-a-chip. You need to provide your own interfaces and extended memory control. A late addition to the chip set was a mostly compatible extended memory chip (medic) but it was rarely used. The 6100 is found in the VT-78 and a few non-DEC machines such as the PCM-12 and Intercept series. These are 2/5 the speed of an 8/e, although DEC chose to use chips only about 60% of that speed in the VT-78. Otherwise the VT-78 is totally compatible with the 8/e configured for the same peripherals, which is a generous set of interfaces compared to an actual 8/e. Most notably absent is the ability to have EAE and no DMA interface was attempted in the VT-78, although in theory this can be done. there is a 6101 (PIE) chip that interfaces to the 6100, but it is not to be used where software compatibility with any existing -8 peripherals is intended. The 6120 is used in DECmates, and is a second-generation chip. The overall speed is comparable to an 8/e, and a few instructions are a little slower, but some are actually slightly faster. EAE isn't implemented, but may be possible. The hooks for it seem to be present. DECmates don't implement it though, nor do they implement a buss structure :-(. There are dedicated slots for certain peripherals, such as a DMA color graphics board, hard-disk or 8" floppies, and an "auxiliary" processor board which contains either a Z80 and 64K or an 8086 with 256K or 512K and a Z80 which shares 64K of the memory space with the 8086. These boards can run CP/M-80 and the XPU can also run a generic MS-DOS. The 6120 supports 32K memory directly, thus there is no medic chip. There is a standard interface chip, 6121, but it's only *almost* compatible with the traditional interfaces of the PDP-8, and the reason that there is a software problem with the machine is that the PDP-8 software depends on the interface being *exactly* compatible, not merely vaguely compatible. The result is the buggy and emasculated OS/278 as compared to the original OS/8. Some of the problems are expedient in nature, some are caused by brain-dead and conflicting conventions imposed by the system ROMs of the machine (not applicable to DECmate I which is more compatible on this point), and the main cause is the problematic 6121 chip which can't be fixed. I have, along with the help of others, prepared a list of steps to take to "repair" OS/278, although some of the repair depends on features not yet documented due to past stonewalling by (former) DEC managers. Today's DEC is more willing to reveal what was done a few years ago, but a lot of the info is scattered, or only known to exist in the hands of people who never had a long-term committment to 12-bit machines. We thank the few of these people who have assisted in certain areas, but it's up to the user community to correct the problems of the (relatively recent) past. I will be posting a list of needed files which ought to be available in source form, which aren't. The tide *is* turning though, although some of it is being acquired the hard way - disassembling the binaries. I have already disassembled the ROMs of the DECmate II (four revisions) and DECmate III (there appears to be only one revision) and have recently acquired a DECmate III+ (likely only one revision here as well). In the process, I acquired enough information to determine the organization of the "slushware" that controls the machine, as read in by the ROM-based code, etc. I am about 60% done with disassembly of that code as well. I have in the process located where the disk boot and partitioning info are held on the hard disk, as well as figured out how to read and write it. The slushware is taking a long time in part because it's fairly long, and partly because it's software "talking" to software, while the ROM is software talking to hardware, and thus more constrained in purpose. Much of the supporting information has been obtained from helpful users who are hardware hackers. They have noticed where DEC uses standard parts from other companies, and provided copies of those companies' spec sheets for the components, such as the SMC Video Interface chips as used in the VT-220 and DECmate II, III, III+, and the 6120 and 6121 as used in all DECmates which is made by Harris Semiconductor. Harris has extensive documentation that only presumes a basic understanding of the PDP-8/e, and a little knowledge gained from earlier Harris and Intersil spec sheets for the 6100 series. Using these spec sheets, and writing a half-dozen utility programs, I was able to figure out how to turn MS-DOS absolute binary .BIN files read from the ROMs into an OS/8 .SV file which in turn was then disassembled. The original files were created using a PC-based PROM blaster to read the chips into the 8-bit binary files, then converted to .BOO files with the MSBMKB program. Then they were sent to the PDP-8 using MS-KERMIT and KERMIT-12. At the PDP-8 end DEBOO.SV was used to create a packed binary file of the ROMs. The resulting files are to be treated as unusual files, because the bit orientation of the binary doesn't match any PDP-8 conventions. The ability to unpack the files as OS/8 is fairly standard, but the contents have to be loaded according to arbitrary conventions. Moreover, the DECmate II version is contained in a set of three ROMs, each of which contains the load information for a different set of eight bits, thus the loading utility has to incorporate three different storing routines for each of the ROM files. The DECmate III and III+ ROMs are loaded in an entirely different format each entirely contained in one ROM which switches loading format at the midpoint. When any one set of three (or one in the III series cases) is loaded, the resultant is exactly one PDP-8 field or 4096 words. This is then the code to be disassembled from the 4K .SV file. When I start the III+ disassembly this will be the sixth 4K disassembly of this family of code I have accomplished. (Fortunately, they are related, so there is a good probability of picking out "familiar" sections of code here and there, so it's not the same as disassembly of 24K of unique code :-).) The sources recreated from these binaries has allowed me to follow the flow and format of the data loaded in from tracks 0, 78, 79, or the equivalent hard disk sectors of the slushware into control panel (CP) memory. This in turn allowed me to write a utility to read the data into memory as it appears in the CP memory in CP fields 0 and 1 (where the CP ROM loads it). The resulting image file is what I am presently disassembling, etc. to become a fully documented source file of the slushware. The 6100 and 6120 both support this slushware concept, meaning there is code outside of the PDP-8's normal addressing space which is entered only via a special form of CP-oriented interrupt. It has higher priority than normal interrupts or non-interruptible code, and runs even if the machine is halted. (On the 6120, normal memory HLT instructions cause a CP interrupt and in CP memory HLT is a NOP. There is a status register to determine that the reason for interrupt to CP memory was in fact a HLT instruction. This allows a no-PDP-8-memory invisible debugger to exist. There is one for the DECmates II III III+ called CPODT (aka CPUODT) that is pretty good. If you run it first from OS/278, any other utility can always be broken out of, because CPODT has access to all operations as part of CP memory. Needless to say, CPODT is on my list of programs to acquire in accurate source form or disassemble. (I have disassembled a small portion of CPODT; just enough to confirm that it loads over certain portions of the slushware in ways I had suspected, but not more than a few percent of it.) Once all issues such as this are resolved, it will be possible to completely "fix" OS/278, and to create a unified OS/8 family system, tentatively dubbed OS/8 V5. It requires small modifications to *all* programs, but the result is one system that runs on all models, just as P?S/8 currently (almost) does. (P?S/8 has already implemented the equivalent to the main problem facing OS/8 regarding the keyboard, but there is a wishlist for P?S/8 as well. Some of this may be resolved by removing known bugs in the DECmate slushware, although it's likely that system software as well as slushware changes will be necessary for total compatibility in both OS/8 family, and P?S/8 systems on all of the models of the "family of 8".) In subsequent postings, I will outline the 6121 incompatibility issue central to the keyboard problem and some tentative solutions, etc. Does anyone else know where these chips can be purchased? The useful chips include 6120, 6121, 6100, 6101, 6102, 6103, and 6402 (UART) models from Harris and Intersil. Spec sheets can likely be provided by readers of the newsgroup. Perhaps we can hear from some of the groups currently implementing PDP-8 chip machines, etc. cjl From news.columbia.edu!sol.ctr.columbia.edu!spool.mu.edu!sgiblab!rtech!ingres!kerry Wed Oct 7 21:45:02 EDT 1992 Article: 28 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!sol.ctr.columbia.edu!spool.mu.edu!sgiblab!rtech!ingres!kerry From: kerry@Ingres.COM (Kerry Kurasaki) Subject: OS-8 Message-ID: <1992Oct7.185551.8168@pony.Ingres.COM> Reply-To: kerry@Ingres.COM (Kerry Kurasaki) Organization: Ask Computer Systems Inc., Ingres Division, Alameda CA 94501 Distribution: na Date: 7 Oct 92 18:55:51 GMT Lines: 2 How many other operating systems do you know where the resident portion was only 256 12-bit words? From news.columbia.edu!sol.ctr.columbia.edu!spool.mu.edu!sgiblab!rtech!ingres!kerry Wed Oct 7 21:49:13 EDT 1992 Article: 29 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!sol.ctr.columbia.edu!spool.mu.edu!sgiblab!rtech!ingres!kerry From: kerry@Ingres.COM (Kerry Kurasaki) Subject: OS-8: Trivia Question Message-ID: <1992Oct7.185715.8365@pony.Ingres.COM> Reply-To: kerry@Ingres.COM (Kerry Kurasaki) Organization: Ask Computer Systems Inc., Ingres Division, Alameda CA 94501 Distribution: na Date: 7 Oct 92 18:57:15 GMT Lines: 5 Does anyone remember when the "End of the World" was for OS-8? And what that meant? Kerry From news.columbia.edu!sol.ctr.columbia.edu!The-Star.honeywell.com!umn.edu!news.orst.edu!sequent!uunet!stanford.edu!agate!garnet.berkeley.edu!tedcrum Wed Oct 7 22:39:53 EDT 1992 Article: 30 of alt.sys.pdp8 Path: news.columbia.edu!sol.ctr.columbia.edu!The-Star.honeywell.com!umn.edu!news.orst.edu!sequent!uunet!stanford.edu!agate!garnet.berkeley.edu!tedcrum From: tedcrum@garnet.berkeley.edu () Newsgroups: alt.sys.pdp8 Subject: Rainbow Taken! Date: 7 Oct 1992 22:22:47 GMT Organization: University of California, Berkeley Lines: 4 Distribution: ba Message-ID: <1avnvnINN3u8@agate.berkeley.edu> NNTP-Posting-Host: garnet.berkeley.edu Keywords: DEC, Rainbow The Rainbow that I was offering has found a new home. Thank you for your response. -Ted Crum From news.columbia.edu!watsun.cc.columbia.edu!lasner Wed Oct 7 22:40:01 EDT 1992 Article: 31 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!watsun.cc.columbia.edu!lasner From: lasner@watsun.cc.columbia.edu (Charles Lasner) Subject: Re: OS-8 Message-ID: <1992Oct8.014823.4092@news.columbia.edu> Sender: usenet@news.columbia.edu (The Network News) Nntp-Posting-Host: watsun.cc.columbia.edu Reply-To: lasner@watsun.cc.columbia.edu (Charles Lasner) Organization: Columbia University References: <1992Oct7.185551.8168@pony.Ingres.COM> Distribution: na Date: Thu, 8 Oct 1992 01:48:23 GMT In article <1992Oct7.185551.8168@pony.Ingres.COM> kerry@Ingres.COM (Kerry Kurasaki) writes: >How many other operating systems do you know where the resident portion >was only 256 12-bit words? But P?S/8' resident portion is only 128 12-bit words for a functional system and 35 words for reloading the system while it is swapped out. This is because paper-tape loaders occupy the other 93 words of the same 128 words. cjl From news.columbia.edu!watsun.cc.columbia.edu!lasner Wed Oct 7 22:40:15 EDT 1992 Article: 32 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!watsun.cc.columbia.edu!lasner From: lasner@watsun.cc.columbia.edu (Charles Lasner) Subject: Re: OS-8: Trivia Question Message-ID: <1992Oct8.023856.5137@news.columbia.edu> Sender: usenet@news.columbia.edu (The Network News) Nntp-Posting-Host: watsun.cc.columbia.edu Reply-To: lasner@watsun.cc.columbia.edu (Charles Lasner) Organization: Columbia University References: <1992Oct7.185715.8365@pony.Ingres.COM> Distribution: na Date: Thu, 8 Oct 1992 02:38:56 GMT In article <1992Oct7.185715.8365@pony.Ingres.COM> kerry@Ingres.COM (Kerry Kurasaki) writes: >Does anyone remember when the "End of the World" was for OS-8? > >And what that meant? > >Kerry Sure, it's DEC 31 1977, the last day of the original inadequate date format. Since then, a kludge is in effect: The contents of location 07777 bits[3-4] represent a two-bit field where each increment means 8 more years. Thus the base year group is either: 1970 1978 1986 1994 depending on the two-bit quantity. (BTW, COS-310 used the identical scheme but starts on a different base year.) Note that there is a typical formatting problem for 2000 and 2001 that all systems have at end-of-century, but at least the date "survives" into the next century a little. Thus DEC 31 2001 is the current drop-dead date. But the current scheme is still a kludge, since there is no info for the determination of the actual base group year bit combination. Thus, we can only "drift" along with our OS/8 files. Any long-time user knows the problem of suddenly "new" files appearing that are actually 8 years old. The bits are used to *presume* the base year, since the files don't contain the needed info to determine it. So, all directory-oriented programs use the following: All files are either this year or the previous 7 years. This means that on Jan 1 of any supported year, files that are actually 8 years old appear to be up to a year in the future. As the year progresses, the problem lessens of course. This could be re-implemented to check if the date in this year is newer than today, thus allowing files to exist in an 8-year period ending today, as opposed to ending on DEC 31 of this year. There is a solution however: The OS/8 directory structure supports the concept of Additional Information Words (AIWs). The default is one AIW, and none is occasionally used by those who need more files in the directory. The OS/8 directory structure is the worst of several worlds: it is a linked structure in theory, but it is laid out sequentially, and specifically in record 1-6 only. The standard system cannot expand the directory, and moreover, while there is a "correct" way to look at the directory that uses the links and terminator, there are programs that "know better" and deal with it as an implied monolith that just happens to be what it is. Thus, if it were to be changed, a lot of programs would "break". Within the limited structure there is room for a few hundred files, the exact number dependent on how many entries for empties there are, and whether there are AIW words present. Since devices can be 4096 records long, it is possible when there are many small files to run out of directory before you run out of physical space. Thus, some users delete the AIW word to maximize (small) file count. But the first AIW word is defined as the date word, so such file structures don't support the date concept at all. There is no official function for any AIWs past the first one, so it could be defined to contain the base group year bits. This would allow an improved system to provide accurate dates for files, at the slight additional expense of lowering the maximum file count slightly more. This wouldn't affect the majority of users whatsoever. Moreover, there have been various attempts at subfiles, which can have their own internal conventions, and thus at least for archival purposes, avoid that problem. The rest of the problem is to determine at least one additional base group year bit, which would then up the drop dead date to DEC 31 2033. I'll look for yet another bit to up the ante to DEC 31 2097. I won't be around to see how the next generation after that handles the problem. P?S/8 solves the problem in a slightly different manner. The base year group is the same quantity of groups of 8 years, only starting at 1960. Four bits are allocated for base group years, so the last group value starts at 2080. Most of the date printing routines are already conditioned for end-of-century conditions, so printing of dates from 1960 through 2099 are handled correctly. The 12-bit P?S/8 equivalent of the AIW represents 8 years worth as in OS/8, but in a different way: The OS/8 date word is divided into separate bit fields. Three are for the year, four for the month in a year, and five for the day within a month. The only advantage of such a scheme is that it's easy to AND off the desired bits for a calculation. However, the bits aren't arranged in an order that leads to sorted dates. (The year is in the low-order bits.) This is unfortunate, and we're stuck with a format where you can't do an arithmetic compare of the binary value to determine whether a file is newer or older, and must instead first create a binary function of the date word for such comparison. This is part of why standard system programs only provide services such as a directory of files with/not with today's date, etc. The P?S/8 date word is the 12-bit value obtained by placing today in a continuum of days derived in sequential order assuming that every month has exactly 31 days. Thus, each mythical year has 372 days in it. Doing the appropriate divide operations can isolate the year, day of the year, or day of the week, current month, current day, etc. as needed. Some of the operations can make use of both the quotient and remainder. All this means is that there are spread throughout the values of the date word some "impossible" dates such as February 30-31, which must be excluded by applications programs. The OS/8 format can have an impossible day 32 of any month, as well as a month 13-16 equally impossible, so there are actually more OS/8 cases of mythical values to avoid. Additionally, the actual term of the date word is not 8 years with this scheme, rather it's about 11-3/4 years. Thus, the date group base year needs to be updated every 8 years as in OS/8, but you have almost 4 years to procrastinate before actually implementing it. The total unique date therefore lasts from 1960 through 2080 plus 11-3/4 years or sometime near the end of 2091. Thus the P?S/8 date scheme lasts for nearly 132 years and occupies 16 bits total. Arithmetic compares suffice to prove whether a file is newer or older than any viable date. cjl From news.columbia.edu!sol.ctr.columbia.edu!caen!uwm.edu!ux1.cso.uiuc.edu!news.iastate.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!news Thu Oct 8 16:10:14 EDT 1992 Article: 33 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!sol.ctr.columbia.edu!caen!uwm.edu!ux1.cso.uiuc.edu!news.iastate.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!news From: jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) Subject: Re: OS-8 Sender: news@news.uiowa.edu (News) Message-ID: <1992Oct8.142915.6201@news.uiowa.edu> Date: Thu, 8 Oct 1992 14:29:15 GMT Distribution: na References: <1992Oct7.185551.8168@pony.Ingres.COM> Nntp-Posting-Host: pyrite.cs.uiowa.edu Organization: University of Iowa, Iowa City, IA, USA Lines: 56 >From article <1992Oct7.185551.8168@pony.Ingres.COM>, by kerry@Ingres.COM (Kerry Kurasaki): > How many other operating systems do you know where the resident portion > was only 256 12-bit words? I wrote a console monitor system for the DDP-516 where the resident system was 15 words of ROM plus 6 words of dedicated peripheral interface registers. The DDP-516 was a 16 bit minicomputer made by Computer Control Corporation and later by Honeywell. My code ran on the 16K word version of this machine (there were options to expand the memory to 64K words). The 15 words of ROM were the bootstrap program that, when started with a program number in the B register, would load that program from disk and run it. The 6 words of dedicated peripheral interface registers held the stream pointers for standard input, standard output and standard binary. One word was either -1 or a disk sector address. If it was -1, that stream was directed to the console, otherwise, the stream was from the indicated disk address. The other word was the byte offset in the sector of the next byte to be read from or written to on that stream. I wrote a shell that used this. The shell included the code needed to translate program names to program numbers, it did I/O redirection for applications run under it, and it had conditional and iterative control structures that operated in terms of the success or failure of the programs it ran (as indicated by termination codes left in the accumulator by those programs). I also wrote patches for the standard Honeywell assembler, Fortran compiler, and linking loader to make them undestand the streams, standard input, standard output and standard binary. As delivered by Honeywell, these were purely paper-tape oriented software; as previously patched, these ran to and from dedicated disk addresses. All this was done at the Bell Labs Accoustics Research Department (Dept 1227) between the summer of 1973 and the summer of 1974. It's worth noting that the DDP 516 computers we had at Bell were workstations on a LAN. There were 3 user workstations, and a 4th DDP 516 used as a file server (it had 4 disk pack transports). There was also a CSP 30 compute-server on the net; this was a 1 mip machine, and it had no I/O except the network. The network was Pierce Loop slotted ring, one of the very first ring networks (I know of only two other experimental token ring networks that existed at the time). Our DDP 516 workstations were, in retrospect, fitted out as good prototypes of modern workstations. Each had a graphics display (backed by two dedicated disk tracks), a mouse, a set of knobs for analog input, a votrax synthesizer for sound output, a high speed ADC for sound input, an electrostatic (Versatek) printer for graphics and text output, and a Diablo Hi Type terminal for a console terminal. In departure from the modern perspective, each also had a card reader, and there was a keypunch beside each workstation. We didn't have a text editor! Doug Jones jones@cs.uiowa.edu From news.columbia.edu!sol.ctr.columbia.edu!zaphod.mps.ohio-state.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!news Thu Oct 8 21:55:12 EDT 1992 Article: 34 of alt.sys.pdp8 Xref: news.columbia.edu comp.sys.dec:10351 alt.sys.pdp8:34 misc.books.technical:1739 alt.folklore.computers:32329 Newsgroups: comp.sys.dec,alt.sys.pdp8,misc.books.technical,alt.folklore.computers Path: news.columbia.edu!sol.ctr.columbia.edu!zaphod.mps.ohio-state.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!news From: jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) Subject: Preservation of old manuals Sender: news@news.uiowa.edu (News) Message-ID: <1992Oct8.211310.11441@news.uiowa.edu> Date: Thu, 8 Oct 1992 21:13:10 GMT Nntp-Posting-Host: pyrite.cs.uiowa.edu Organization: University of Iowa, Iowa City, IA, USA Lines: 631 I have been asked to post something on this topic, and it got a bit longer than I expected. =================================CUT====================================== An Introduction to Bookbinding Particularly aimed at the preservation of old DEC handbooks By Douglas Jones jones@cs.uiowa.edu 1992 CONTENTS INTRODUCTION PREPARATION FOR PHOTOCOPYING PHOTOCOPYING COLLATING AND FOLDING MAKING A COVER PUNCHING THE PAGES SEWING THE PAGES TO THE COVER TRIMMING THE PAGES MAKING DUST JACKETS INTRODUCTION after 1966, DEC began printing their logic handbooks and CPU reference manuals in a paperback format on inexpensive pulp paper. This had the merit that the books were inexpensive, but the shelf-life of the books was not much greater than the market life of the hardware. For those of us who are trying to restore old computer systems, it means we have to use handbooks that are printed on yellow, brittle paper. I have consulted with people at the University of Iowa Book Conservation Laboratory, and they say that there is a simple test used to determine if the paper on which a book has been printed is beyond saving. Dog-ear a page; if the dog-ear breaks off at the crease after folding and reverse folding, the paper is beyond saving. This does not mean that the book itself is worthless! It is ripe for photocopying, and if the the copies are made on archival paper and properly bound, they will last for centuries with reasonable care. I wouldn't recommend undertaking this project more than once for any particular book! It's lots of work! Read this whole report before trying it yourself. The process I'm describing destroys your copy of the book in the process of making one or more new copies. If your copy has sentimental value, you might not want to do this. Furthermore, if anyone else has done the job, you may be able to cut your work in half if they saved an unbound photocopy that can be re-copied for you. Finally, this writeup applies to manuals that are bound in book form -- if you've got a looseleaf binder or spiral bound manual, it's all quite a bit easier; you simply remove the pages from the binder, photocopy them, punch them and hang them in a new binder. You'll still want permission to make a photocopy, and the advice below on archival paper selection still applies. PREPARATION FOR PHOTOCOPYING Once you have concluded that a paperback is beond repair, the first step in preserving its contents is to complete its destruction. Slice off the glued spine of the book, so that the pages come apart as separate sheets. You can cut the sheets from the spine with an X-acto knife, or you can find a shop with a paper shear that will cut the spine loose. Here in Iowa City, one of the larger copy shops has a shear; they charge $2 a cut, which isn't a bad price considering the total cost of the project. Keep the pages in order! The next step is to tape the pages into pairs for copying so that the pairs can be folded and sewn into a bound hardback book. If you examine commercially bound books, you will find that the pages are organized into "signatures" of 4 to 16 sheets (always a power of two), and we are about to reconstruct such a signature structure. Get a supply of white paper tape, "Scotch Brand Post-It Tape" works very well; it took three rolls to make up DEC's "Introduction to Programming 1973". Make a jig for taping your pages out of a single sheet of standard size typing paper. This is the size paper you will be making the photocopys on. Note that two pages, side by side, of the original book are slightly smaller than the sheet of typing paper. You will need a margin in the middle of each copied sheet to sew the binding and similar margins around the edges are no problem, so draw the following layout diagram on your sheet of paper: ______________________________________________ | __________________ __________________ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |<---------------->| | | | | | Width of one | | | | | | page cut from | | | | | | paperback | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |__________________| |__________________| | |______________________________________________| The gap between the outlines of the two pages must be narrower than the white tape, enough narrower that a strip of tape can get a firm grip on each page without covering any print. Note that DEC paperbacks were cheaply made, and that this means that they frequently had sloppy centering of the printed material on each page. Now you are ready to set to work. Take the stack of original pages, in order, right side up, and turn over the top 8 sheets, placing them beside the stack as if they were still bound to a common spine. Then pick off the top sheet of the left stack and put it on the left square of your jig and put the top sheet of the right stack on the right square of your jig, and tape them together, being careful not to shift their alignment. Pause to doctor any dirt specks, pencil marks or other marks that might spoil your photocopy, then flip the pair of taped together pages, tape them together on the flip side, and doctor that side, if needed, before setting the pair of pages aside. Do not turn over pages except when turning blocks of 8 or when flipping pairs of pages, an operation done once with each pair! This greatly simplifies keeping the book in order through this process! Keep making pairs of pages, where each pair consumes the top page from each of two piles of pages, until you have exhausted the smaller pile. At this point, you will have a pile of 8 pairs of pages. this is the prototype of one of the reconstructed signatures of the book. Having carefully set aside your a signature, turn another block of 8 pages and repeat the process, reconstructing the next signature. In copying DEC's 1973 Introduction to Programming, I found (from occasional ink smears and other printing defects) that the 8 sheet signatures I reconstructed were the original signatures as printed for DEC. The book was made of 19 such signatures, which comes to 152 double sheets of paper. In the original printing, each signature was printed on one sheet of newsprint that was then folded 4 times and cut to size before being glued into a paperback binding. PHOTOCOPYING When talking with a photocopy shop about copying what is obviously a book, they'll demand permission to make a copy. I got permission by calling 1-800-DEC-DIRECT; they referred me to the right person, who told me to fax a request for permission. They faxed me a letter of permission a week or two later. In my letter asking permission, I made it clear that I was interested in preserving out of print documentation, and I made it clear that I intended to trade some of my photocopies for other hard to get documentation. DEC required that I include a statement that the copies were made by premission with the DEC copyright notice. Since you most likely have over 100 sheets of paper that need copying, check a variety of photocopying houses, looking for a good price. Your taped pairs of pages are too fragile to be put through an automatic sheet feeder, and because they are slightly undersize, they will need to be hand centered on the glass of the copying machine. Most photocopying houses will charge you extra for hand placement of originals. When I copied DEC's Introduction to Programming, the handling charge was $0.05 per page, but some places charge up to $0.25. You've done a bit of work to make up page pairs, and you'll want the copies to last, so get them photocopied on archival paper; 25% cotton bond typically costs a penny or two extra per sheet. For DEC's 1973 Introduction to Programming, the total cost of paper, copying and special handling came to $0.20 a two-sided sheet for the first copy and $0.11 a sheet for all subsequent copies. That means that my first photocopy of the entire book cost $30.40, while subsequent copies cost $16.72. At these prices, I strongly recommend making extra copies! You have just destroyed a copy of a book that is out of print, so why not make a few extra copies; also, keep one copy in unbound form in case you or anyone else ever want more copies. The copy will be on good paper, so it can be put in an automatic sheet feeder, avoiding special handling charges. To minimize the problems you have with your photocopying house, provide them with the jig you used to paste up your pages and say you want them centered exactly as shown by the outlines on that jig. Then give them the jig and say they're free to cut out the center of the page and stick it to the glass of their photocopying machine with post-it tape to help them center the copy. If they screw up the centering, you can and should get hard nosed about it. Finally, tell them to keep the signatures together! Make it clear that you don't want your pages shuffled. Collating costs a bit extra, so I decided to do it myself, but I asked them to cleanly separate each signature from the next in the stack of copies I got, and to keep the sheets in order. They did. COLLATING AND FOLDING When you get your copies back from the photocopy shop, you'll have a box of paper, and you want to have a box of books. The steps you need to go through before binding the books are collating the pages of each signature, folding the signatures, and collating the signatures. Collating a signature is easiest if you pay the photocopying shop to do it for you, since they have collating photocopying machines. Lacking this, lay out the 8 piles of paper representing the 8 sheets that make up the first signature and pick the top page off each pile to make one signature. Stack them so that the top page in the stack has consecutive page numbers on top, and so that reading up one side of the pile and down the other, the page numbers are in order. You may have to shuffle things a bit before you get the hang of this, but it's not hard once you get going. Once you finish collating the first signature of each copy of your book, set it aside and collate the second signature of each copy. Keep the collated signatures for each copy together, stacked in order, so that you will end up with each book in a separate pile. If you don't want a hardback book, stop here! Cut each signature in half where you would otherwise fold it, then either punch the holes needed to hang the page in a downsized 3 ring binder or have it punched and spiral bound. A sewn binding is more durable, but it's lots of work. The final step prior to binding each copy of the book is to fold the signatures that will make up that book. I do this freehand, rolling the 8-page bunch that makes up one signature until the edges are even, then holding the edges together with one hand while I crease it with the other. When you get all the signatures of one copy of the book folded, they won't stack very well because the creases aren't properly set. To set the creases, force the books into a neat stack and clamp them that way overnight. Lacking a bookpress, stack an unabridged dictionary or a few volumes of the encyclopedea on top of the pile of folded signatures. MAKING A COVER You've got a decent book now, on archival paper, and you need a cover that will be reasonably durable. A full hard-backed case binding is a big project, so I'll recommend something less, a long-stitched soft-board binding. This was recommended to be by the book conservation lab at the University of Iowa. The cover is made of cardboard -- specifically acid free two ply museum board. Good art-supply stores carry this. A sheet will make about eight book covers. In determining the size of the cover, you have to allow for not only the thickness of the paper, but the thickness of the thread used to sew the binding, so now is the time to get the thread. Traditionally, unbleached linen thread is the preferred material, but unbleached long-staple cotton will do almost as well. The key is that it is a natural fiber comparable in expected lifetime to the paper and the cover material, and it has very long fibers, giving it great strength. The thread should be heavy, heavy enough that you might rate it as fine cordage as easily as rating it as heavy thread! Thread diameters of close to a millimeter (when uncompressed and not under tension) are quite reasonable. The thread should compress to about 1/2 millimeter when successive turns are wrapped tightly around a pencil. If you have 19 signatures, as in DEC's 1973 Introduction to Programming, you'll need to add the thickness of 19 threads to the thickness of your book. To find this, wrap 19 turns of thread tightly around a pencil and measure the length of the wrapping. The museum board has the interesting property that it flexes fairly easily in one dimension but it is fairly stiff in the other direction. You want your cover to flex easily from side to side, since that's the way you tend to bend the covers of a book when you hold it open to read. You want the book to be stiff from top to bottom, since bending in that direction should never happen. Taking this into account, cut a rectangle of museum board with the following dimensions: ______________________________________________ _______ __ | __________________ _____^____________ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | >|--|<-- Thickness | | | | | | | | | of the | | | | | | | | | thread. |<-------------------------------------------->| | | | | Width and height of one | | | | | | | unfolded sheet of one of | | | | | | | your signatures, that is, | | |<----->| | -- Thickness | | a sheet of typing paper. | | | | | of the | | | | | | | | | stacked | | | | | | | | | pages (not | | | | | | | | | measured | | | | | | | | | at creased | |__________________| |_____|____________| | | | edge!) |_______________________________v______________|_______|__| |<-------->| Planned thickness of spine of book. Do not cut the cover oversize. This cover is intended to cover the pages of the book in roughly the way a conventional paperback cover does, with the edges of the cardboard exactly even with the edges of the bound pages. I did all my cutting with a carpenter's square to guide a large X-acto knife. It took two or three scores with the knife to cut all the way through, and I used a sheet of crummy cardboard as backing so I wouldn't cut into the table top. Having cut out a rectangular piece of cardboard, you need to score the creases where the cover will hinge to wrap around the pages. I measured twice, then set my straight-edge along the planned hinge lines and used a blunt tool (the rounded corner of a smaller metal ruler) to score the crease. You don't want to cut or tear the fibers of the board when you do this, only compress them to guide the crease. _________________________________________________________ | | | | | ||--------|| | | | | | | ||--------|| | | | | | | ||--------|| | | | | | | ||--------|| | | | | | | ||--------|| | | | | | | ||--------|| | | | | | | ||--------|| | | | | | | ||--------|| | |_______________________|__________|______________________| Before you bend the cover, you need to cut a series of equally spaced square-ended slits in the cover. Typically, these should be about an inch apart, (anywhere from 2 to 3 cm will do) and the end slits should be closer to the ends (about 1/2 inch or 1.5 cm is nice). Each slit should be about 1 mm wide, but the precise width is less important than the uniformity. I cut 8 slits for this purpose, but 7 would be just as good. The ends of the slits should come to about 1/2 the thickness of one signature from the creases that you just scored. PUNCHING THE PAGES Paper is hard stuff, and pushing a sewing needle through 8 layers is no fun, so it is far easier to pre-punch each signature! To do this, make a jig out of a scrap of cardboard with a very straight edge. First, cut a shallow wide notch in the cardboard. The depth of the notch should be about the thickness of 8 sheets of paper. The width of the notch should be the height of the finished book. Then, put the jig parallel to the length of the spine, so the notch just brackets the cover and carefully mark where each slot in the spine passes your jig. Finish the jig by making a V shaped notch at each mark. These notches show where each hole goes in the signatures. It's a rare day that you can get the slots in your spine perfectly symmetrical, so mark one end of your jig as up, so that you can punch all of your signatures the same way. Always make the up direction point towards the top of the page, and you'll get an even book as a result. Here's you jig, resting against the spine: | __ __ __ __ __ ____| || || || || || |____ | |____||________||________||________||________||____| | | \/ \/ \/ \/ \/ | | | | UP -------> | |____________________________________________________________| | | The purpose of the V shaped notches is to guide the tip of an awl as you punch holes in your signatures. Rest the notched edge of your jig in the crease of a folded signature, with the back of the fold against a wood block, and use a good sharp awl to punch holes. Keep the signature folded fairly tightly, and the awl will find the center of the crease in the signature and the center of the notch fairly naturally. SEWING THE PAGES TO THE COVER Now, you're ready to sew the book! The long stitch I used is a fairly modern modification of an ancient style of stitching; the basic rules are simple: Each signature is sewn to the cover in turn, starting at the front of the book. The thread runs once, the length of each signature, alternately inside the fold of the signature and outside the spine of the cover. The thread always runs inside the fold of the signature at the ends of the book. Except at the ends, the threads of successive signatures take turns being inside and outside. Looking at the back of a finished book with 4 signatures that follows these rules, you'll see something like this: __________________________________________ | | Start -->|---|------| |------| |------| _-| |-_=| |------| |------| |=--| |- |------| |------| |------| _-| End ---->|---|------|------| |------| |=--| |__________________________________________| The book is sewn with a single thread, between the indicated points. Note that it takes a bit of cleverness to sew the ends of the signatures, since the natural alternation of over and under brings the thread out somewhat randomly in one or the other orientation. Note that the thread always passes over the end of each signature and around the end of the spine. This helps prevent the pages from tearing out, because tears almost always begin at the end of the crease. Before you start sewing, you need to measure out enough thread to sew the entire book. For a book with 19 or 20 signatures, wrap the thread 10 times around the handfull of signatures when they're clenched tightly in the cover. Then wrap one or two turns for good luck. It's better to have a bit of extra thread than to have to knot the thread in midbook! Before you start sewing, it helps (but is not strictly necessary) to wax the thread with beeswax. To do this, clamp the thread against a block of beeswax with your thumb and pull it through with your other hand. The thread will tend to cut a slot in the wax, so keep changing the angle of pull to even out the wear on the wax. Do this two or three times with the full length of thread before you start sewing. Here, in some detail, is a cross section of the knotting at the end of a thread: loose end ______ _________\ _________ _______ / \ / \\/ \ / | ====== X ========= X ========= \ ======== / ======= \______/ \_________/ \________/ Try to keep the knot and the loose end on the inside of the book. A tight square knot will do well here. You'll begin by making this knot at one end of the first signature, then finish sewing the first signature to the spine. At the end, you'll face a problem -- how to finish one signature and start the next. A note of caution: The final quality control check happens when you commit yourself to sewing in a signature! Once the wrong signature is sewn in or the right one is sewn in with a missing or inverted page, it's no fun to undo. Check what signature you are sewing, and make sure it is all there! Also, with each signature, check that all the pre-punched holes line up with the slits in the cover. If they don't you've probably got the signature upside down. If they still don't line up, you've done a bad job punching the holes, and you'll have to repunch a few. Here, in some detail is the sewing pattern used to change from one signature to the next. If the thread emerges from the end of a signature in the crease of that signature, go outside the cover and down into the prepunched hole in the next signature, then out the crease, over the spine, and through the same hole as you begin sewing the length of the next signature. If the thread emerges from the end of a signature outside the spine, go around the end and down the crease, re-using the last hole in the same signature before going outside, around the end of the next signature, and up the crease. In both cases, the above sewing pattern will produce a result that looks like the following: // | ======= and // thread outside back of spine. |###---------========== // | // ------- thread hidden in fold of signature. |// |---=========---------- ####### thread outside and hidden along | the same line. Whenever you use the same hole twice, always be sure not to sew the thread through itself. Pull the thread that goes through the hole off to one side, then thread the needle through to the other side of the same hole. As you reach the end of the book, it will get hard to squeeze the last signatures in. You'll have to press hard to move the already bound pages down the spine to make room for the last signatures, and as you work on the very last one, you'll have to squeeze the book again each time you try to get the needle through. If you measured the spine width correctly, you'll just barely manage to fit the last signature in -- that's the test of a perfect fit. If you run out of thread before you reach the end of the book, follow the instructions below for tightening the thread before you tie on a new length of thread! Otherwise, you'll end up with a knot that you may well have to pull through a hole in the sewing when you try to tighten the thread later. Before you tie the final knot in the book, tighten the thread, working along the spine from the inital knot towards the end, pulling out any slack until the thread is uniformly tight throughout the sewing. I use a sharp awl (the same one I used to punch the holes in the signatures) to do this, since it is easy to insert the tip under a tight loop of thread and pull the slack forward to that loop, tightening the previous loop. You don't need to pull too hard, but you don't want to leave any slack in the binding. Finally, when the sewing is uniformly tight, tie the final knot, and you have a book! If the pages aren't in the right order at this point, though you'll have trouble fixing the order without cutting the thread and re-sewing! TRIMMING THE PAGES You now have a book, but you'll notice that the pages don't come out even along the "working edge" of the book. The innermost pages of each signature stick out farther than the others, and this makes it hard to thumb through the book. People who do "art bookbinding" seem to like this irregularity, but for a book you intend to be read, it's worth trimming the pages to make an even face. The easy way to do this is to take the book to a place that can shear off the edges. The same shear that works for trimming off the spine of the original book will also serve to trim the pages of the new book, so if you can have the book trimmed for only a few dollars, do so. Tell the people who are trimming the book to square up the edge before they trim it, and then take off about 1/8 inch or 3 mm. If you've got appropriate margins around your photocopies, this shouldn't cut into the images of the original pages. Do not try to have the top and bottom trimmed! No matter how irregular this is, your thread reaches all the way to both ends of the spine many times, and trimming the top and bottom would cut it! You can make a tool to trim your own book out of a wood chisel (1/2 inch or 15 mm minimum width) and a few blocks of hardwood. You'll need two planks about 3/4 inch or 2 cm thick and a few inches longer than the book to use as clamps. Clamp the book loosely between these planks, using C clamps or bolts through the ends of the planks, then square up the irregular edge of the book by pressing it edge down on a tabletop. Use shims about 1/8 inch thick to hold the two planks back from the irregular edge (I used thin LEGO bricks). The edges of the planks define the plane along which you will trim the book. Once you have the book squared up, with the squared edge protruding the right distance from the clamps, tighten the clamps down hard, being careful not to disturb the squareness of the assembly. Now, you're ready to plow off the rough edges with your chisel, except that you need a jig to help hold the flat of the chisel exactly in the plane of the faces of your plank clamps. Here's my jig: __________________________________________ | Hardwood Jig | __________ | _______________ | | chisel |__| |__ | | | handle |__|____________|__\/\/\/\/\/\|_|_____________| |__________| ^ | |||||||||||| | | | jaw |||||||||||| jaw | flat of chisel | of ||| book ||| of |<-- In retrospect, I is held exactly |clamp||| |||clamp| think that this in plane of base | || || | jaw should have of jig. | | | | been thicker! I held the chisel into my plowing jig with a pair of countersunk wood screws that grasped the shank of the blade between the handle and flat. As shown in the above picture, the chisel looks a bit blunt and it's just starting to cut into the pages on the left edge of the book. To cut with this plow, hold the jig at a slight incline and stroke the sharp edge of the blade gently against the edge of the book, working along the full length of the book with each stroke. Better to go too slow than too fast! If you try to cut quickly, you'll gouge your pages. It is crucial that your chisel be very sharp, and there must be no bevel at all on the flat side of the blade! Careless sharpening will frequently put a slight bevel on the flat side, and this will make your plowing ride up as you work across the book instead of allowing you to hold to one plane. MAKING DUST JACKETS Your cardboard cover has threads that show on the outside, and it has no title or cover art! You can solve both of these problems with a paper dust cover. I used 11 by 17 (double the size of the typing paper on which the book was copied) paper as a dust jacket. If you're lucky, you'll have an original cover that you can photocopy onto the dust jacket for cover art, but by the time a book has reached the point where this kind of project is worth while, this is unlikely. I did some cut-and-paste work with photocopies of parts of the body of the book to reconstruct an approximation of the typography of the original cover, then photocopied this onto a colored paper dust jacket before cutting it to shape. Here's a plan for a good archival dust jacket: _ The line of this crease is _______ ___ _______ / critical -- start this fold / \ | | / \ | with the book closed; otherwise _________ /_________\|___|/_________\__________ the cover will tend | | | | | | to pull the book open. | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |<-- fold the end over | | | | | | first. | | | | | | | | | | | | |_________|___________|___|___________|_________| \ /| |\ / \_______/ |___| \_______/ <-- fold these flaps over second, ^ and tape or glue to the folded | end flap. Flap to fold under (if you are jacketing an already jacketed book, carefully tuck it into the end of spine). this is the first step in folding the book cover onto the book. The 11 by 17 paper I used (the largest size the photocopying shop could handle) wasn't long enough to fully jacket the insides of the cardboard book covers, so I used photocopies of the insides of the original cover as "end papers", gluing them to the dust jacket (but not to the cardboard cover) with PVA cement after the dust jacket was folded on. You'll need to clamp the book shut to keep the paper flat while the glue dries, but this raises the risk of some glue leaking out and sticking to the rest of the book. To prevent this, insert sheets of wax paper between the sheet you are gluing and the page it shouldn't stick to. If you intend to use the book much, I recommend wrapping the paper dust jacket in a mylar jacket -- mylar drafting film is the ideal stuff. Use "magic transparent tape" to hold the mylar dust jacket on (it's also made of mylar), taping the jacket to itself, not to the book. DO NOT USE VINYL DUST JACKETS! Vinyl sticks to xerographic copies, pulling the ink from the paper, and it is slightly acid, speeding the corrosion of the paper. Polyethylene is ok. From news.columbia.edu!sol.ctr.columbia.edu!usc!cs.utexas.edu!torn!utzoo!censor!isgtec!bmw Fri Oct 9 15:00:20 EDT 1992 Article: 35 of alt.sys.pdp8 Xref: news.columbia.edu alt.sys.pdp8:35 alt.folklore.computers:32365 Path: news.columbia.edu!sol.ctr.columbia.edu!usc!cs.utexas.edu!torn!utzoo!censor!isgtec!bmw From: bmw@isgtec.com (Bruce M. Walker) Newsgroups: alt.sys.pdp8,alt.folklore.computers Subject: Re: Wanted: Unused PDP-8? Message-ID: <3405@isgtec.isgtec.com> Date: 9 Oct 92 10:23:19 GMT References: <1992Oct5.170334.12874@tc.cornell.edu> <1992Oct5.234213.4863@news.columbia.edu> <1992Oct6.104738.21099@cbnewsl.cb.att.com> Sender: news@isgtec.com Distribution: na Organization: ISG Technologies Inc., Mississauga Ontario Lines: 26 In article <1992Oct6.104738.21099@cbnewsl.cb.att.com> rl@cbnewsl.cb.att.com (roger.h.levy) writes: > > I am quite sure that at one time there was a microprocessor that fully > emulated the PDP-8. Is there still a supply of these chips? You are referring to the Intersil IM6100 processor "family". 5 to 10 volt CMOS, various speed grades from 4 to 8 MHz. Originally appeared about 1976; Harris second-sourced them and also came out with an improved version, the 6120 (co-designed with DEC? ... cl will elaborate :-) I rather doubt that either company makes these any more ... 'tis a shame. I have a few myself, along with the companion chips: the 6102 MMU, timer and DMA combo, the 6101 PIE (peripheral interface element: kind of port decoder/timing controller), and some 6402 CMOS UARTs. Sorry, not for sale! These'll either get built into my home-brew PDP8 project that I started in 1977 (so it's been a long time coming, what about that garage you promised yourself you'd clean out? sheesh!), or held for their antique value. When PDP8 architecture comes back into vogue, and everyone wants one, I'll be able to sell these things and retire comfortably. -- "The path of my life is strewn with cowpats from the devils' own herd." -- Edmund Blackadder II bmw@isgtec.com [ ...!uunet.ca!isgtec!bmw ] Bruce Walker From news.columbia.edu!rpi!zaphod.mps.ohio-state.edu!swrinde!sdd.hp.com!sgiblab!news.kpc.com!decwrl!netcomsv!netcom.com!rbp Fri Oct 9 22:08:09 EDT 1992 Article: 36 of alt.sys.pdp8 Xref: news.columbia.edu comp.sys.dec:10374 alt.sys.pdp8:36 misc.books.technical:1746 alt.folklore.computers:32371 Newsgroups: comp.sys.dec,alt.sys.pdp8,misc.books.technical,alt.folklore.computers Path: news.columbia.edu!rpi!zaphod.mps.ohio-state.edu!swrinde!sdd.hp.com!sgiblab!news.kpc.com!decwrl!netcomsv!netcom.com!rbp From: rbp@netcom.com (Bob Pasker) Subject: Re: Preservation of old manuals Message-ID: <1992Oct9.210751.5006@netcom.com> Organization: Netcom - Online Communication Services (408 241-9760 guest) References: <1992Oct8.211310.11441@news.uiowa.edu> Date: Fri, 9 Oct 1992 21:07:51 GMT Lines: 8 i forwarded this article to my friend who is a preservation librarian for the reserach libraries group. she said it is quite a good description of how to preserve manuals. she also recommended Book-Lab in austin, TX, who performs archival photocopying for libraries and will probably take jobs from individuals as well. -- --- bob pasker ---- rbp@netcom.com From news.columbia.edu!rpi!jwilson Tue Oct 13 15:29:10 EDT 1992 Article: 37 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!rpi!jwilson From: jwilson@unix.cie.rpi.edu (John Wilson) Subject: PC incrementing Message-ID: <_byz88_@rpi.edu> Nntp-Posting-Host: unix.cie.rpi.edu Organization: CIE, Rensselaer Polytechnic Institute, Troy, NY Date: Sun, 11 Oct 1992 20:09:30 GMT Lines: 12 I'm sure someone (cjl?) will know the answer to this nitpicky question... When an MRI occurs in the last word of a page (+177) and has bit 4 set ("this page" as opposed to page 0), is the datum accessed on this page or the next one? That is to say, by the time the high 5 bits of the PC have been prepended to the low 7 bits of the instruction, has the PC been incremented yet? I would just try it but my 8/e is in Boston... Thanks, John From news.columbia.edu!rpi!think.com!spool.mu.edu!sgiblab!rtech!ingres!kerry Tue Oct 13 15:32:42 EDT 1992 Article: 38 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!rpi!think.com!spool.mu.edu!sgiblab!rtech!ingres!kerry From: kerry@Ingres.COM (Kerry Kurasaki) Subject: Another OS/8 trivia question Message-ID: <1992Oct12.182840.22117@pony.Ingres.COM> Reply-To: kerry@Ingres.COM (Kerry Kurasaki) Organization: Ask Computer Systems Inc., Ingres Division, Alameda CA 94501 Date: 12 Oct 92 18:28:40 GMT Lines: 4 Wow! Some pretty sharp netters out there. Here's another one: Anyone know how OS/8 knows if batch is running? That is, how does KMON know to get stuff from the file instead of the keyboard? From news.columbia.edu!sol.ctr.columbia.edu!spool.mu.edu!yale.edu!jvnc.net!johnson Tue Oct 13 15:33:09 EDT 1992 Article: 39 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!sol.ctr.columbia.edu!spool.mu.edu!yale.edu!jvnc.net!johnson From: johnson@tigger.jvnc.net (Steven L. Johnson) Subject: Re: Another OS/8 trivia question Message-ID: <1992Oct13.032611.7348@tigger.jvnc.net> Originator: johnson@tigger.jvnc.net Sender: news@tigger.jvnc.net (Zee News Genie) Nntp-Posting-Host: tigger.jvnc.net Organization: JvNCnet References: <1992Oct12.182840.22117@pony.Ingres.COM> Date: Tue, 13 Oct 1992 03:26:11 GMT Lines: 10 kerry@Ingres.COM (Kerry Kurasaki) writes: >Anyone know how OS/8 knows if batch is running? That is, how does >KMON know to get stuff from the file instead of the keyboard? By looking at location 7777 in field 0. Actually I knew it was someplace in the last few words of field 0, but had to look it up to remember which one. -Steve "been a few years since I wrote disk drivers for OS/8" From news.columbia.edu!rpi!usenet.coe.montana.edu!caen!sol.ctr.columbia.edu!spool.mu.edu!sgiblab!rtech!ingres!kerry Tue Oct 13 15:47:58 EDT 1992 Article: 40 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!rpi!usenet.coe.montana.edu!caen!sol.ctr.columbia.edu!spool.mu.edu!sgiblab!rtech!ingres!kerry From: kerry@Ingres.COM (Kerry Kurasaki) Subject: Re: Another OS/8 trivia question Message-ID: <1992Oct13.171324.3141@pony.Ingres.COM> Reply-To: kerry@Ingres.COM (Kerry Kurasaki) Organization: Ask Computer Systems Inc., Ingres Division, Alameda CA 94501 References: <1992Oct12.182840.22117@pony.Ingres.COM> <1992Oct13.032611.7348@tigger.jvnc.net> Date: 13 Oct 92 17:13:24 GMT Lines: 16 In article <1992Oct13.032611.7348@tigger.jvnc.net> johnson@tigger.jvnc.net (Steven L. Johnson) writes: > >>Anyone know how OS/8 knows if batch is running? That is, how does >>KMON know to get stuff from the file instead of the keyboard? > >By looking at location 7777 in field 0. Actually I knew it >was someplace in the last few words of field 0, but had to look >it up to remember which one. > And the bonus question: What should the value be at that location and what is the significance of that value? Gee, you guys ARE good! From news.columbia.edu!watsun.cc.columbia.edu!lasner Tue Oct 13 15:48:17 EDT 1992 Article: 41 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!watsun.cc.columbia.edu!lasner From: lasner@watsun.cc.columbia.edu (Charles Lasner) Subject: Re: PC incrementing Message-ID: <1992Oct13.192851.5504@news.columbia.edu> Sender: usenet@news.columbia.edu (The Network News) Nntp-Posting-Host: watsun.cc.columbia.edu Reply-To: lasner@watsun.cc.columbia.edu (Charles Lasner) Organization: Columbia University References: <_byz88_@rpi.edu> Date: Tue, 13 Oct 1992 19:28:51 GMT In article <_byz88_@rpi.edu> jwilson@unix.cie.rpi.edu (John Wilson) writes: >I'm sure someone (cjl?) will know the answer to this nitpicky >question... > >When an MRI occurs in the last word of a page (+177) and has bit >4 set ("this page" as opposed to page 0), is the datum accessed >on this page or the next one? That is to say, by the time the >high 5 bits of the PC have been prepended to the low 7 bits of >the instruction, has the PC been incremented yet? > >I would just try it but my 8/e is in Boston... > >Thanks, John Real easy. Look at the register flow: First update PC to fetch your instruction at say 0377. It goes into the memory buffer. Then the PC is updated to 0400. Note that if an ISZ and it skips, that could make it 0401, but in any case the PC is out of the loop. The effective address is calculated from the MB, not the PC's pointings at that point. Moreover, the MB can be uses as a pointer as well, and even an autoindexed one in the case of indirect through what (was) in 0010-0017 before writing that location back. In any case, eventually the effective address is calculated and put into the memory address, since the MA is where the memory comes from, not the PC. (Yes, earlier the PC -> MA was performed to fetch the instruction from memory.) So, the answer is that there is no special relationship with falling through a page. The page where the instruction is stored is the current page for all effective address calculation purposes. An alternate comment: The PDP-8/e panel is an economy measure, and doesn't really tell what's going on. The earlier machines make it clear in the lights what's in what when and where. Some of the confusion is clearly caused by always reading a bunch of lights merely labeled "memory address" without regard to whose address it is at the moment, etc. An interesting side note for simulators: There have been -8 simulators written that aren't compatible on a similar point: falling off the end of a field, not a page. Regardless of instruction type, some programs do the un-PDP-8-ly thing of going to the next FIELD, not to location 0000 of the current field. Of course little software, even diagnostics, ever check for this! (Although I did once write a piece of bootstrap-time once-only code in a particular handler that needed this to work right! Thus, a simulator with that peripheral in it would flunk :-).) cjl From news.columbia.edu!watsun.cc.columbia.edu!lasner Tue Oct 13 15:49:09 EDT 1992 Article: 42 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!watsun.cc.columbia.edu!lasner From: lasner@watsun.cc.columbia.edu (Charles Lasner) Subject: Re: Another OS/8 trivia question Message-ID: <1992Oct13.194705.6091@news.columbia.edu> Sender: usenet@news.columbia.edu (The Network News) Nntp-Posting-Host: watsun.cc.columbia.edu Reply-To: lasner@watsun.cc.columbia.edu (Charles Lasner) Organization: Columbia University References: <1992Oct12.182840.22117@pony.Ingres.COM> <1992Oct13.032611.7348@tigger.jvnc.net> <1992Oct13.171324.3141@pony.Ingres.COM> Date: Tue, 13 Oct 1992 19:47:05 GMT In article <1992Oct13.171324.3141@pony.Ingres.COM> kerry@Ingres.COM (Kerry Kurasaki) writes: > >And the bonus question: > > What should the value be at that location and what is the > significance of that value? > >Gee, you guys ARE good! If bit[0] of 07777 is a one, batch is running. If you want to interact with it, the source of the BAT handler is useful info for this. Look in the PDP-8 archives for it on ftp.telebit.com where it is or will be soon. Bits[6-8] are the software core size where 000 and 111 both mean 32K is available because they both mean the highest field available is 7. Bits[3-4] are the date base group year bits currently, where each increment is 8 years starting at 1970-77 going to 1994-2001. Since it's getting close to the end of the world, I want a definition for all the bits so I can at least double the lifetime, if not quadruple it. So please find me a bit or two, preferably in that word. Anyone know what all of the other 6 bits mean? cjl From news.columbia.edu!sol.ctr.columbia.edu!spool.mu.edu!sgiblab!rtech!ingres!kerry Tue Oct 13 21:22:57 EDT 1992 Article: 43 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!sol.ctr.columbia.edu!spool.mu.edu!sgiblab!rtech!ingres!kerry From: kerry@Ingres.COM (Kerry Kurasaki) Subject: Re: Another OS/8 trivia question Message-ID: <1992Oct13.231916.25065@pony.Ingres.COM> Reply-To: kerry@Ingres.COM (Kerry Kurasaki) Organization: Ask Computer Systems Inc., Ingres Division, Alameda CA 94501 References: <1992Oct12.182840.22117@pony.Ingres.COM> <1992Oct13.032611.7348@tigger.jvnc.net> <1992Oct13.171324.3141@pony.Ingres.COM> <1992Oct13.194705.6091@news.columbia.edu> Date: 13 Oct 92 23:19:16 GMT Lines: 15 In article <1992Oct13.194705.6091@news.columbia.edu> lasner@watsun.cc.columbia.edu (Charles Lasner) writes: >> >>And the bonus question: >> >> What should the value be at that location and what is the >> significance of that value? >> >If bit[0] of 07777 is a one, batch is running. If you want to interact with >it, the source of the BAT handler is useful info for this. Look in the PDP-8 >archives for it on ftp.telebit.com where it is or will be soon. > Actually, there is an additional check made to ensure that Batch was not corrupted/overwritten. It's been a looooooong time, but there is a magic value in ??? location 0200 ??? in the batch field. What is that value and what is the significance of it? From news.columbia.edu!rpi!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!destroyer!news.iastate.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!jollie@zambini.cs.uiowa.edu Thu Oct 15 15:15:37 EDT 1992 Article: 44 of alt.sys.pdp8 Xref: news.columbia.edu alt.sys.pdp8:44 comp.sys.dec:10442 comp.sys.dec.micro:1769 vmsnet.pdp-11:423 Newsgroups: alt.sys.pdp8,comp.sys.dec,comp.sys.dec.micro,vmsnet.pdp-11 Path: news.columbia.edu!rpi!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!destroyer!news.iastate.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!jollie@zambini.cs.uiowa.edu From: jollie@zambini.cs.uiowa.edu (Jeffrey C. Ollie) Subject: Getting DEC's permission to redistribute PDP-8 software and manuals Sender: news@news.uiowa.edu (News) Message-ID: <1992Oct15.050926.2951@news.uiowa.edu> Date: Thu, 15 Oct 1992 05:09:26 GMT Nntp-Posting-Host: kelso.cs.uiowa.edu Organization: University of Iowa Lines: 16 Hi, I was wondering if anyone knew who to contact at Digital to obtain permission to redistribute some of their copyrighted material. What I have are a bunch of manuals and listings of various software for the PDP-8. Most of the stuff is copyrighted 1965 or 1966. The manuals I plan to photocopy, the software listings I plan to photocopy and convert to an electronic form. There are also a number of programs on paper tape that I'll convert once I get a paper tape reader up and running. Please e-mail me, I'll summarize for the net. Jeff Ollie jollie@zambini.cs.uiowa.edu "The Happy User" From news.columbia.edu!sol.ctr.columbia.edu!zaphod.mps.ohio-state.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!news Wed Oct 28 14:38:01 EST 1992 Article: 45 of alt.sys.pdp8 Xref: news.columbia.edu alt.folklore.computers:32914 alt.sys.pdp8:45 Newsgroups: alt.folklore.computers,alt.sys.pdp8 Path: news.columbia.edu!sol.ctr.columbia.edu!zaphod.mps.ohio-state.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!news From: jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) Subject: Re: New owner of a PDP-8e Sender: news@news.uiowa.edu (News) Message-ID: <1992Oct27.194507.21093@news.uiowa.edu> Date: Tue, 27 Oct 1992 19:45:07 GMT References: <1992Oct27.102532.60147@cc.usu.edu> Nntp-Posting-Host: pyrite.cs.uiowa.edu Organization: University of Iowa, Iowa City, IA, USA Lines: 43 >From article <1992Oct27.102532.60147@cc.usu.edu>, by ivie@cc.usu.edu (CP/M lives!): > In article , > eru@tnso04.tele.nokia.fi (Erkki Ruohtula) writes: >> A strange word size. How do you normally process characters on this box? > > The primary choices are 6-bit characters (this is 1963, after all) or > 7-bit characters with the 8th bit set to one and the remaining bits > unused. Well, he said an 8/e, and that was 1969. The end of the line for the PDP-8 family was in 1990, with the DECmate III+, which is well into the ASCII era. >From the start, all PDP-8 files have been stored as 8 bit ASCII, which is to say, 7 bit ASCII with the high bit set to one. The reason is that these machines were used, from the start, with teletypes (preferably model ASR-33) which used a 64 character subset of this code (upper case only). Initially, most software development was done with punched paper tape, so it was natural to process one character per 12 bit word. Error messages and other text constants that were embedded in programs were frequently stored in a compact 6 bit character set, with special routines to unpack the codes. When ASCII is packed into 12 bit words, triplets of ASCII characters are packed into pairs of words, two successive characters in the two successive words, right justified, and the third character split into two nibbles and stored left justified in the remaining nibbles of both words. I have 1964 through 1966 vintage source listing of large amounts of PDP-8 system software (such as the FORTRAN compiler and both the PAL and MACRO-8 assemblers), and these very clearly document the standards used for text processing back then on this family of machines. > > Anyone planning a big bash for the PDP-5's 30th birthday? No, but someone ought to do so! Who's got a working PDP-5 to use as the centerpiece of the celebration? DEC ought to be willing to help with the price of beer and publicity. Doug Jones jones@cs.uiowa.edu From news.columbia.edu!rpi!zaphod.mps.ohio-state.edu!uwm.edu!ux1.cso.uiuc.edu!usenet.ucs.indiana.edu!silver.ucs.indiana.edu!russ Wed Oct 28 14:38:11 EST 1992 Article: 46 of alt.sys.pdp8 Xref: news.columbia.edu alt.folklore.computers:32932 alt.sys.pdp8:46 Newsgroups: alt.folklore.computers,alt.sys.pdp8 Path: news.columbia.edu!rpi!zaphod.mps.ohio-state.edu!uwm.edu!ux1.cso.uiuc.edu!usenet.ucs.indiana.edu!silver.ucs.indiana.edu!russ From: russ@silver.ucs.indiana.edu (Jeff Russ) Subject: Re: New owner of a PDP-8e Message-ID: Sender: news@usenet.ucs.indiana.edu (USENET News System) Nntp-Posting-Host: silver.ucs.indiana.edu Organization: Indiana University References: <1992Oct27.102532.60147@cc.usu.edu> <1992Oct27.194507.21093@news.uiowa.edu> Date: Wed, 28 Oct 1992 04:32:36 GMT Lines: 15 In article <1992Oct27.194507.21093@news.uiowa.edu> jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) writes: >> Anyone planning a big bash for the PDP-5's 30th birthday? > >No, but someone ought to do so! Who's got a working PDP-5 to use as the >centerpiece of the celebration? DEC ought to be willing to help with the >price of beer and publicity. I've got an intact PDP-5 but no schematics or manuals. If anyone has any leads who might have some please let me know. I'll pay in cash or beer. ---------------------------------------------------------------------------- Jeff Russ russ@silver.ucs.indiana.edu University Computing Services PHONE: (812) 855-2733 Indiana University, Bloomington, IN I want to buy old PDP[4-9] systems. From news.columbia.edu!watsun.cc.columbia.edu!lasner Wed Oct 28 14:41:55 EST 1992 Article: 47 of alt.sys.pdp8 Xref: news.columbia.edu alt.folklore.computers:32935 alt.sys.pdp8:47 Newsgroups: alt.folklore.computers,alt.sys.pdp8 Path: news.columbia.edu!watsun.cc.columbia.edu!lasner From: lasner@watsun.cc.columbia.edu (Charles Lasner) Subject: Re: New owner of a PDP-8e Message-ID: <1992Oct28.053731.7883@news.columbia.edu> Sender: usenet@news.columbia.edu (The Network News) Nntp-Posting-Host: watsun.cc.columbia.edu Reply-To: lasner@watsun.cc.columbia.edu (Charles Lasner) Organization: Columbia University References: <1992Oct26.093701.60119@cc.usu.edu> <1992Oct27.051054.7198@news.columbia.edu> Date: Wed, 28 Oct 1992 05:37:31 GMT In article eru@tnso04.tele.nokia.fi (Erkki Ruohtula) writes: >In article <1992Oct27.051054.7198@news.columbia.edu> lasner@watsun.cc.columbia.edu (Charles Lasner) writes: >>If an 8/a-type expander box is added to an 8/e, then the KT8A or CESI >>memory extensions are possible. The KT8A provides for up to 128K, and the >>CESI MEC8 and static RAM memory boards allow up to 512K. BTW, these are 12-bit >>words, not bytes, so it's 768K of 8-bit bytes, which is more than a PC-XT >>can have, or any MS-DOS real-mode environment on a PC, etc. > >A strange word size. How do you normally process characters on this box? >As 6 six-bit characters in a word, or as 12 bit characters (the latter >certainly would be good for international applications!) There have been several coding schemes used on the -8 over the years: OS/8 used 8-bit characters packed three into two adjacent 12-bit words. This 24-bit scheme is repeated as necessary. Standard file format is line terminator is CR and LF, and a ^Z at the end. The high-bit is to be stripped as it can't be trusted. This is not a limitation of the O/S, rather of the typical appliation programs. There exists an alternate set of utilities that use an alternate set of conventions where ^A is used as a terminator, and it consists of an editor, a text processor, and an assembler. You are virtually forced to consider them a set, although it's fairly easy to mostly convert back and forth from these utilities from DISC Systems to DEC's standard CUSP's. If the files are binary, then of course the data is 8-bit, but in a format that uses the same packing scheme as for ASCII text, except that the data is the same as the original paper-tape 8-bit frames. Only the loader and related utilities understand this underlying format. Other utilities use their own formats, since the only requirement is that the data is representable as contiguous blocks of 12-bit words. Memory-image files are essentially just that, with the exception of a header block that indicates loading instructions for the rest of the file. The directory entries are in six-bit subset ASCII, since the file names are caseless. There have also been other encoding schemes: a six-bit code can be used for 7-bit ASCII where one code is reserved as a case shift. This is how the internal coding of FOCAL, 1969 is performed, as well as the old OS/8 editor which is a hacked-up version of the original paper-tape editor. The notion is that case shifting happens infrequently, so you are accepting the tradeoff that it is high overhead. There are two variants: the case is either transient, or it is locking and a flip-flop. Either method has advantages and disadvantages depending on application. The method chosen for these programs for their internal operation is the transient form. On file operations to the O/S, they convert from their internal format to the OS/8 7-bit format. Some systems have been written for pure upper-case languages. In this case, the format is six-bit ASCII, which in turn comes in two flavors: ASCII-40 and ASCII&77. The first tends to "invert" the character codes, and the second tends to keep the same values, at least for half of the codes, and the other half is still reminiscent of the original value. Either can be easily converted back to the original 7-bit form. WPS-8 uses an 8-bit character code, where the high-bit is used to initiate various extensions to the basic ASCII text characters. Some functions implemented are embolden delimiters, underline delimiters, ruler definition delimiters, soft-return, etc. Character codes for the VT8E are 12-bit codes, since you have to include the character attribute bits. This is a DMA device, and programming it is similar to, and a forerunner of the typical micro video interface, where you poke at memory to create the screen you see. In fact, I once wrote a terminal emulator for the VT8E. Since it is intrinsically a 6-bit-only device, I simulated case by bolding the upper-case only. There exists a TECO implementation for this hardware that does precisely this, and chars are displayed as bold "$" chars, etc. Due to the high DMA rate, the screen updates are equivalent to a serial baud rate of approx. 3/4 MegaBaud. Since the file systems impose no restrictions other than 12-bit representation, it is possible to use 12-bit chars, or 24-bit chars, or even 36-bit or 48-bit chars. As is possible on any other machine, there is no real limit, just that there is a granularity at some level of 12-bits. On the PDP-10, the same principle applies, except this level of granularity is 36 bits/word. There are so many 8-bit-byte-oriented systems today, that most people have simply lost track of how to pack words with character codes, usually taken from smaller sets than the word size. Simple co-routines are used to do this packing and unpacking which run quite efficiently both of speed and size. Some custom applications have been written for PDP-8's in the typesetting world. They tend to use specialized 6, 7, or 8-bit codes, packed as necessary into the host O/S's 12-bit format, but they are hardly similar to ASCII. I have written programs to deal with "ANPA ASCII" which is a severely modified code based partially on ASCII with some extensions added from the type-setting world (and some curious deletions!). Since it is expressable in 8-bit, I just packed it in the standard way: three chars in 2 12-bit words. Note that all disk blocks are even-word sizes. This means that there is no waste in storing the characters into the blocks, although the 8-bit character count is an even multiple of 3. OS/8 standard would be 384 chars/block since the blocks are 256 12-bit words. (There are 128 pairs of words or 128 triple 8-bit bytes.) cjl From news.columbia.edu!watsun.cc.columbia.edu!lasner Wed Oct 28 14:44:00 EST 1992 Article: 48 of alt.sys.pdp8 Xref: news.columbia.edu alt.folklore.computers:32936 alt.sys.pdp8:48 Newsgroups: alt.folklore.computers,alt.sys.pdp8 Path: news.columbia.edu!watsun.cc.columbia.edu!lasner From: lasner@watsun.cc.columbia.edu (Charles Lasner) Subject: Re: New owner of a PDP-8e Message-ID: <1992Oct28.055205.8193@news.columbia.edu> Sender: usenet@news.columbia.edu (The Network News) Nntp-Posting-Host: watsun.cc.columbia.edu Reply-To: lasner@watsun.cc.columbia.edu (Charles Lasner) Organization: Columbia University References: <1992Oct27.102532.60147@cc.usu.edu> <1992Oct27.194507.21093@news.uiowa.edu> Date: Wed, 28 Oct 1992 05:52:05 GMT In article <1992Oct27.194507.21093@news.uiowa.edu> jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) writes: >From article <1992Oct27.102532.60147@cc.usu.edu>, >by ivie@cc.usu.edu (CP/M lives!): >> In article , >> eru@tnso04.tele.nokia.fi (Erkki Ruohtula) writes: >>> A strange word size. How do you normally process characters on this box? >> >> The primary choices are 6-bit characters (this is 1963, after all) or >> 7-bit characters with the 8th bit set to one and the remaining bits >> unused. > >Well, he said an 8/e, and that was 1969. The end of the line for the >PDP-8 family was in 1990, with the DECmate III+, which is well into the >ASCII era. Earliest 8/e prototype I am aware of is late 1970. > >From the start, all PDP-8 files have been stored as 8 bit ASCII, which is >to say, 7 bit ASCII with the high bit set to one. The reason is that >these machines were used, from the start, with teletypes (preferably >model ASR-33) which used a 64 character subset of this code (upper case >only). Initially, most software development was done with punched paper >tape, so it was natural to process one character per 12 bit word. Let's make that a little clearer: OS/8 was started in 1970, and that's the way *it* does it! In essence, mistrust and strip out the high-order bit, since you can't trust what the terminals might set the bit to. Teletypes generally set it, but other devices might vary, such as VT05 terminals introduced slightly earlier. Before that was the Disk Monitor, whose ASCII format was the case-shift method using 6-bit upper-case code and a transient case-control character for the (presumedly) infrequent occurence of lower-case. There are other systems, but this is what DEC supported. > >Error messages and other text constants that were embedded in programs >were frequently stored in a compact 6 bit character set, with special >routines to unpack the codes. These are the programmer's methods of storing strings within his programs loaded into 12-bit memory, not the O/S's method of storing the source files. The six-bit code could either be "straight" and upper-case only, or with a locking or transient case-shifter as required. Also, some codes can be reserved for other functions such as imbedded CR/LF impliers, etc. This allows multi-line messages at the expense of the loss of certain reserved characters. The P?S/8 upper-case file structure uses 6-bit storage, with the "_" character removed and instead it implies (^I). The "@" char is also disallowed and is used for both EOL and EOF. (It serves both purposes by using a trick of "alignment".) P?S/8 is a proprietary alternate O/S for the -8's and DECmates, and is not a DEC product. > >When ASCII is packed into 12 bit words, triplets of ASCII characters are >packed into pairs of words, two successive characters in the two >successive words, right justified, and the third character split into >two nibbles and stored left justified in the remaining nibbles of both >words. This is known as "3 for 2" and is quite commonly used. Even binary paper-tape-frame files use this format, except that each 8-bit char now uses all 8 bits, while ASCII text only uses the low-order 7 bits of each 8 bits. > >I have 1964 through 1966 vintage source listing of large amounts of PDP-8 >system software (such as the FORTRAN compiler and both the PAL and MACRO-8 >assemblers), and these very clearly document the standards used for text >processing back then on this family of machines. >> >> Anyone planning a big bash for the PDP-5's 30th birthday? > >No, but someone ought to do so! Who's got a working PDP-5 to use as the >centerpiece of the celebration? DEC ought to be willing to help with the >price of beer and publicity. > Doug Jones > jones@cs.uiowa.edu I once worked on a -5, but I don't have one, but I do have a few Systems Modules such as were used in it :-). cjl From news.columbia.edu!sol.ctr.columbia.edu!zaphod.mps.ohio-state.edu!cis.ohio-state.edu!magnus.acs.ohio-state.edu!usenet.ins.cwru.edu!agate!overload.lbl.gov!s1.gov!jtk Thu Oct 29 13:01:31 EST 1992 Article: 49 of alt.sys.pdp8 Xref: news.columbia.edu alt.folklore.computers:32961 alt.sys.pdp8:49 Newsgroups: alt.folklore.computers,alt.sys.pdp8 Path: news.columbia.edu!sol.ctr.columbia.edu!zaphod.mps.ohio-state.edu!cis.ohio-state.edu!magnus.acs.ohio-state.edu!usenet.ins.cwru.edu!agate!overload.lbl.gov!s1.gov!jtk From: jtk@s1.gov (Jordin Kare) Subject: Re: New owner of a PDP-8e Message-ID: <1992Oct28.235258.4581@s1.gov> Sender: usenet@s1.gov Nntp-Posting-Host: s1.gov Organization: LLNL References: <1992Oct27.102532.60147@cc.usu.edu> <1992Oct27.194507.21093@news.uiowa.edu> Date: Wed, 28 Oct 1992 23:52:58 GMT Lines: 20 In article <1992Oct27.194507.21093@news.uiowa.edu> jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) writes: >> >> Anyone planning a big bash for the PDP-5's 30th birthday? > >No, but someone ought to do so! Who's got a working PDP-5 to use as the >centerpiece of the celebration? DEC ought to be willing to help with the >price of beer and publicity. > Doug Jones > jones@cs.uiowa.edu Migawd! 30 years of PDP-5's! You might check with the MIT Electronics Research Society, room 20B119 (?) at MIT. They used to have a PDP-5 (I know because I rebuilt it, long ago in my college days) and may well either still have it or know where it went. Geoff Rochat would be the person to ask. Jordin Kare -- Jordin Kare jtk@s1.gov 510-426-0363 From news.columbia.edu!rpi!zaphod.mps.ohio-state.edu!cis.ohio-state.edu!magnus.acs.ohio-state.edu!usenet.ins.cwru.edu!agate!darkstar.UCSC.EDU!cats.ucsc.edu!mmcohen Thu Oct 29 13:02:41 EST 1992 Article: 50 of alt.sys.pdp8 Xref: news.columbia.edu alt.folklore.computers:32965 alt.sys.pdp8:50 Path: news.columbia.edu!rpi!zaphod.mps.ohio-state.edu!cis.ohio-state.edu!magnus.acs.ohio-state.edu!usenet.ins.cwru.edu!agate!darkstar.UCSC.EDU!cats.ucsc.edu!mmcohen From: mmcohen@cats.ucsc.edu (Michael M Cohen) Newsgroups: alt.folklore.computers,alt.sys.pdp8 Subject: 8L Date: 29 Oct 1992 03:02:33 GMT Organization: University of California; Santa Cruz Lines: 13 Message-ID: <1cnk89INNb2m@darkstar.UCSC.EDU> NNTP-Posting-Host: si.ucsc.edu Wondering if there are any museums that could provide a home for our old PDP-8/L #167. It ran last time I tired it (about 5years ago?). -- ====================================================================== = Dr. Michael M. Cohen mmcohen@dewi.ucsc.edu = = Program in Experimental Psychology mmcohen@fuzzy.ucsc.edu = = 433 Clark Kerr Hall 408-459-2655 LAB = = University of California - Santa Cruz 408-459-2700 MSGS = = Santa Cruz, CA 95064 408-459-3519 FAX = ====================================================================== From news.columbia.edu!sol.ctr.columbia.edu!caen!uwm.edu!ux1.cso.uiuc.edu!news.iastate.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!news Fri Oct 30 00:16:54 EST 1992 Article: 51 of alt.sys.pdp8 Newsgroups: alt.sys.pdp8 Path: news.columbia.edu!sol.ctr.columbia.edu!caen!uwm.edu!ux1.cso.uiuc.edu!news.iastate.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!news From: jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) Subject: FAQ Sender: news@news.uiowa.edu (News) Message-ID: <1992Oct29.225942.2625@news.uiowa.edu> Date: Thu, 29 Oct 1992 22:59:42 GMT Nntp-Posting-Host: pyrite.cs.uiowa.edu Organization: University of Iowa, Iowa City, IA, USA Lines: 437 Frequently Asked Questions about the PDP-8 By Douglas Jones, jones@cs.uiowa.edu (with help from a number of others) Contents What is a PDP? What is a PDP-8? What is the PDP-8 instruction set? What different PDP-8 models were made? Where can I get a PDP-8 today? Where can I get PDP-8 documentation? What operating systems were written for the PDP-8? What programming languages were supported on the PDP-8? Where can I get PDP-8 software? Where can I get additional information? What use is a PDP-8 today? What is a PDP? For over a decade, all programmable digital computers sold by Digital Equipment Corporation were sold as Programmable Data Processors (PDPs) instead of computers. I have DEC documentation that actually calls them "PDPs", so this is not improper usage. DEC's first computer, the PDP-1, had a selling price of $120,000 at a time when competing machines were selling for over $1,000,000. Everyone (DEC's stockholders included) knew that computers were big and expensive and needed a computer center and a large staff, and apparently, DEC chose to avoid dealing with these stereotypes by entirely avoiding the term "computer". DEC built a number of different computers under the PDP label, of which the PDP-8 family machines were the smallest and least expensive. The PDP-10, for example, was a large machine worthy of a computer center and large support staff. The PDP-14 wasn't even a computer -- it was a ROM based industrial controller. The PDP-11, a 16 bit minicomputer/microprocessor family, is the only DEC product still being sold under the PDP name. What is a PDP-8? The PDP-8 family of minicomputers were built by Digital Equipment corporation between 1965 and 1990. These machines were characterized by a 12 bit word, with no hardware byte structure, a 4K minimum memory configuration, and an extremely simple instruction set. By 1970, the PDP-8 was the best selling computer in the world, and many models of the PDP-8 set new records as the least expensive computer on the market. The PDP-8 has been described as the model-T of the computer industry. Gordon Bell (who later was chief architect of the PDP-11 and who, as Vice President, oversaw the development of the VAX) says that the basic idea of the PDP-8 was not really original with him. He gives credit to Seymour Cray (of CDC and later Cray) for the idea of a single-accumulator 12 bit minicomputer. Cray's CDC 160 family, sold starting around 1959, certainly was a very similar 12 bit architecture, and the peripheral processors of Cray's first supercomputer, the CDC 6600, also look very familiar to PDP-8 programmers. What is the PDP-8 instruction set? The PDP-8 word size is 12 bits, and the basic memory is 4K words. The minimal CPU contained the following visible registers: PC - the program counter, 12 bits. AC - the accumulator, 12 bits. L - the link, 1 bit, commonly prefixed to AC as . Instruction words are organized as follows: _ _ _ _ _ _ _ _ _ _ _ _ |_|_|_|_|_|_|_|_|_|_|_|_| | | | | | | op |i|z| addr | op - the opcode i - the indirect bit (0 = direct, 1 = indirect) z - the page bit (0 = page zero, 1 = current page) addr - the word in page. The top 5 bits of the 12 bit program counter give the current page, and memory addressing is also complicated by the fact that absolute memory locations 8 through 15 are used for auto-increment addressing -- if they are used for indirect addressing, they are automatically incremented prior to each use. The basic instructions are: 000 - AND - and operand with AC 001 - TAD - add operand to (a 13 bit value) 010 - ISZ - increment operand and skip if result is zero 011 - DCA - deposit AC in memory and clear AC 100 - JMS - jump to subroutine 101 - JMP - jump 110 - IOT - input/output transfer 111 - OPR - microcoded operations The ISZ and other skip instructions conditionally skip the next instruction in sequence. The subroutine calling sequence involves putting the return address in word zero of the subroutine, with execution starting with word one. Return from subroutine is done with an indirect jump through the return address. The IOT instruction has the following form: _ _ _ _ _ _ _ _ _ _ _ _ |1|1|0|_|_|_|_|_|_|_|_|_| | | | | | | device | op | The IOT instruction specifies one of 8 operations on one of 64 devices; typical operations were skip if device ready, or data from device with accumulator, and transfer data from accumulator to device. IOT operations could start DMA transfers and test their status (DMA was called "data break" on the PDP-8 family). Some CPU functions are accessed only by IOT instructions. For example, interrupt enable and disable are IOT instructions, as are instructions controlling the optional memory management and protection unit that is needed to address more than 4K words. A wide variety of operations are available through the OPR microcoded instructions: _ _ _ _ _ _ _ _ _ _ _ _ Group 1 |1|1|1|0|_|_|_|_|_|_|_|_| 1 - CLA - clear AC 1 - CLL - clear the L bit 1 - CMA - ones complement AC 1 - CML - complement L bit 1 - IAC - increment 1 0 0 - RAR - rotate right 0 1 0 - RAL - rotate left 1 0 1 - RAR - rotate right twice 0 1 1 - RAL - rotate left twice In general, the above operations can be combined by oring the bit patterns for the desired operations into a single instruction. The exception to this is that IAC cannot be combined with the rotate operations on some models, and attempts to combine rotate operations have different effects from one model to another. When these operations are combined, they operate top to bottom in the order shown above. _ _ _ _ _ _ _ _ _ _ _ _ Group 2 |1|1|1|1|_|_|_|_|_|_|_|0| 1 0 - SMA - skip on AC < 0 \ 1 0 - SZA - skip on AC = 0 > or 1 0 - SNL - skip on L /= 0 / 1 1 - SPA - skip on AC >= 0 \ 1 1 - SNA - skip on AC /= 0 > and 1 1 - SZL - skip on L = 0 / 1 - CLA - clear AC 1 - OSR - or switches with AC 1 - HLT - halt The above operations may be combined by oring them together, except that there are two distinct incompatible groups of skip instructions. When combined, SMA, SZA and SNL, skip if one or the other of the indicated conditions are true, while SPA, SNA and SZL skip if all of the indicated conditions are true (logical and). When combined, these operate top to bottom in the order shown. A third group of operate microinstructions (with a 1 in the least significant bit) deals with the optional extended arithmetic element to allow such things as hardware multiply and divide. What different PDP-8 models were made? The following basic models of the PDP-8 were sold by DEC: MODEL DATES SALES COST TECHNOLOGY COMPATABILITY PDP-5 63-65 Transistor Limited PDP-8 65-68 >1000 <$100K Transistor Full LINC-8 66-69 153 $38500 Transistor Full (1) PDP-8/S 67? >1000? <$10K Transistor Limited and slow! PDP-8/I 68? >2000? <$100K TTL Full PDP-8/L 68? >2000? <$100K TTL Full (2) PDP-12 69-71 3500 <$100K TTL Full (3) PDP-8/E 70-78 >10K? $7390 TTL MSI Omnibus Full (4) PDP-8/F 73-78? >10K? <$7K TTL MSI Omnibus Full (uses 8/E CPU) PDP-8/M 73-78? >10K? <$7K TTL MSI Omnibus Full (an OEM 8/F) PDP-8/A 75-84? >10K? <$7K TTL LSI Omnibus Full (new CPU) (5) VT78 78-80 > ? Microprocessor Full (Intersil IM6100) Dm I (6)80-84 Microprocessor Full (Intersil IM6120) Dm II 82-86 Microprocessor Full (IM6120) Dm III 84-90 Microprocessor Limited expansion Dm III+ 85-90 Microprocessor Limited expansion (7) Notes (1) The LINC-8 combined a modified PDP-8 with a Laboratory Instrumentation Control Computer (developed at Lincoln Labs in the early 1960s). (2) The PDP-8/L was intended as a scaled down version of the PDP-8/I, and most of them had only 4K memory, but eventually, a full range of upgrade options were sold. (3) The PDP-12 was originally designated the LINC-8/I; it was a follow-on to the LINC-8; it had the most impressive standard control panel of any PDP-8. (4) The PDP-8/E is considered by many to be the definitive PDP-8. If the PDP-8 was the model-T of the computer industry, perhaps the PDP-8/E was the model-A. (5) After 1978, Reuters bought almost all of the remaining PDP-8/A production run (5-6 years at 1000/month). (6) Dm stands for DECmate. (7) The total sales figure for the PDP-8 family is estimated at over 300,000 machines. Over 8500 of these were sold prior to 1970. When possible, the costs given above are for a minimal system consisting of 4K of main memory, a console teletype, and the minimal software needed to use the machine (FOCAL, BASIC, or a paper-tape based assembler). Additional information on costs and production is needed! The above list does not include many PDP-8 variants sold by DEC to meet the needs of various special users. For example, the Industrial-8 was really just a PDP-8/E with a different nameplate and color scheme. Burger King had thousands of PDP-8/M based point-of-sale systems with no standard peripherals. In addition, DEC made many peripheral controllers for the PDP-11 and PDP-15 that used IM6100 microprocessors. The following PDP-8 compatable or semi-compatable machines were made and sold by others; very little is known about many of these: MODEL DATE MAKER, NOTES MP-12 6? Fabritek TPA 68? Hungarian, possibly a DEC PDP-8/L in drag DCC-112 70-71 Digital Computer Controls DCC-112H 71 Digital Computer Controls 6100 Sampler 7? Intersil, their IM6100 promotional kit Intercept 7? Intersil, based on IM6100 Intercept Jr 7? Intersil, based on IM6100 SBC-8 84-88 CESI, Based on IM6120, SCSI bus Where can I get a PDP-8 today? The CESI machine may still be on the market, for a high price, but generally, you can't buy a new PDP-8 anymore. There are quite a few PDP-8 machines to be found in odd places on the used equipment market. They were widely incorporated into products such as computer controlled machine tools, X-ray diffraction machines, and other industrial and lab equipment. Many of them were sold under the EduSystem marketing program to public schools and universities, and others were used to control laboratory instrumentation. Reuters bought the tail end of the production run. If you can't get real hardware, you can get emulators. Over the years, many PDP-8 emulators have been written; the best of these are indistinguishable from the real machine from a software prespective, and on a modern high-speed RISC platform, these frequently outperform the hardware they are emulating. Where can I get PDP-8 documentation? The 1973 Introduction to Programming was probably DEC's definitive manual for this family, but it is out of print, and DEC was in the habit of printing much of their documentation on newsprint with paperback bindings, which is to say, surviving copies tend to be yellow and brittle. DEC distributed huge numbers of catalogs and programming handbooks in this inexpensive paperback format, and these circulate widely on the second-hand market. When research laboratories and electronics shops are being cleaned out, it is still common to find a few dusty, yellowed copies of these books being thrown in the trash. Maintenance manuals are harder to find, but more valuable. Generally, you'll need to find someone who's willing to photocopy one of the few surviving copies. Fortunately, DEC has been friendly to collectors, granting fairly broad letters of permission to reprint obsolete documentation, and the network makes if fairly easy to find someone who has the documentation you need and can get copies. What operating systems were written for the PDP-8? A punched paper-tape library of stand-alone programs was commonly used with the smallest (diskless and tapeless) configurations from the beginning up through the late 1970's. Many paper tapes from this library survive to the present at various sites! The DECtape Library System was an early DECtape oriented save and restore system that allowed a reel of tape to hold a directory of named files that could be loaded and run. Eventually, this supported a very limited tape-based text editor for on-line program development. The 4K Disk Monitor System provided slightly better facilities. This supported on-line program development and it worked with any device that supported 129 word blocks (DECtape, the DF32 disk, or the RF08 disk). MS/8 or the R-L Monitor System, developed starting in 1966 and submitted to DECUS in 1970. P?S/8, developed starting in 1971 from an MS/8 foundation. Runs on minimal PDP-8 configurations, supports device semi-independant I/O and a file system on a random-access device, including DECtape. OS/8, developed in parallel with P?S/8, became the main PDP-8 programming environment sold by DEC. The minimum configuration required was 8K words and a random-access device to hold the system. TSS/8 was developed in 1968 as a timesharing system. It required a minimum of 12K words of memory and a swapping device. It was the standard operating system on the EduSystem 50 which was sold to many small colleges and large public school systems. Other timesharing systems developed for the PDP-8 include MULTI-8, ETOS, and OMNI-8; these were similar to TSS/8, and by the mid 1970's, many of these were true virtual machine operating systems in the same spirit as IBM's VM-370. WPS was DEC's word processing system that was widely used on the 1980's vintage machines with a special WPS keyboard replacing the standard keyboard. COS-310, DEC's commercial operating system for the PDP-8, supported the DIBOL language. COS-310 was a derivative of OS/8, but with a new text file format. What programming languages were supported on the PDP-8? The PAL family of assembly languages are as close to a standard assembly language as can be found for the PDP-8. These produce absolute object code and versions of PAL will run on minimally configured machines. MACRO-8 was DEC's first macro assembly language for the PDP-8, but it was never used outside the paper-tape environment. MACREL and SABR are assembly languages that produce relocatable output. SABR is the final pass for the ALICS II FORTRAN compiler, and MACREL was developed in (unfulfilled) anticipation of similar use. A subset of FORTRAN was supported on both the PDP-5 and the original PDP-8. Surviving documentation describes a DEC compiler from 1964 and a compiler written by Information Control Systems from 1968. The latter, ALICS II FORTRAN, was originally a paper tape based compiler, but it forms the basis of the OS/8 8K FORTRAN compiler. RTPS FORTRAN required 8K and a floating point processor; it had real-time extensions and was a full implementation of FORTRAN IV (also known as ANSI FORTRAN 66). FOCAL, an interpretive language comparable to BASIC was available on all models of the family, including the PDP-5 and PDP-8/S. BASIC was also available, and was widely used on PDP-8 systems sold under the EduSystem marketing program. A paper-tape version was available that ran in 4K, there were versions that ran under OS/8 and TSS/8, and there was an 8K stand-alone time-sharing version. DIBOL was DEC's attempt at competing with COBOL in the commercial arena. Algol was available from a fairly early date. At least two Pascal compilers were developed for the PDP-8. At least two LISP interpreters were written for the PDP-8; one runs in 4K, the other can use up to 16K. TECO, the text editor, is available, and is also a general purpose language, and someone is working on a PDP-8 C. Where can I get PDP-8 software? DECUS, the DEC User Society, is still alive and well, and their submission form still lists PAL-8 and FOCAL as languages in which they accept submissions! There is a young but growing FTPable archive of PDP-8 software at ftp.telebit.com in directory /pub/pdp8. Where can I get additional information? The file WHAT-IS-A-PDP8, by Charles Lasner contains considerable additional information; this file is included in the FTPable archive cited above. This file gives details of every model of the PDP-8, including the small quirks and incompatabilities that (to be generous) allow software to determine which model it is running on. These quirks also make it all too easy for careless programmers to write almost portable software with very obscure bugs. The mailing list pdp8-lovers@ai.mit.edu reaches a number of PDP-8 owners and users, not all of whom have USENET feeds. The USENET newsgroup alt.sys.pdp8 is fairly new, but someday, the newsgroup and mailing list will be gatewayed to each other. Many "archival" books have included fairly complete descriptions of the PDP-8; among them, "Computer Architecture, Readings and Examples" by Gordon Bell and Allen Newell is among the most complete (and difficult to read). Considering Bell's role in the design of the PDP-8 and the history of DEC, the description in this book should be accurate! What use is a PDP-8 today? What use is a Model T today? Collectors of both come in the same basic classes. First, there are antiquarians who keep an old one in the garage, polished and restored to new condition but hardly ever used. Once a year, they warm it up and use it, just to prove that it still works, but they don't have much practical use. In the second class are those who find old machines and soup them up, replacing major parts to make a hotrod that only looks like the original from the outside, or keeping the old mechanism and putting it to uses that were never intended. Last, there are the old folks who still use their old machines for their intended purposes long after any sane enconomic analysis would recommend such use. If it ain't broke, don't fix it, and if it can be fixed, why bother replacing it? Both Model T Fords and the classic PDP-8 machines are simple enough that end users can maintain and repair them indefinitely. From news.columbia.edu!rpi!uwm.edu!caen!sol.ctr.columbia.edu!eff!iWarp.intel.com|ssd.intel.com!ssd.intel.com!prp Sat Oct 31 00:41:12 EST 1992 Article: 52 of alt.sys.pdp8 Xref: news.columbia.edu alt.folklore.computers:33021 alt.sys.pdp8:52 Newsgroups: alt.folklore.computers,alt.sys.pdp8 Path: news.columbia.edu!rpi!uwm.edu!caen!sol.ctr.columbia.edu!eff!iWarp.intel.com|ssd.intel.com!ssd.intel.com!prp From: prp@ssd.intel.com (Paul Pierce) Subject: Re: New owner of a PDP-8e Message-ID: <1992Oct30.215616.17369@SSD.intel.com> Sender: usenet@SSD.intel.com Nntp-Posting-Host: nautilus Organization: Intel References: <1992Oct27.102532.60147@cc.usu.edu> <1992Oct27.194507.21093@news.uiowa.edu> Date: Fri, 30 Oct 1992 21:56:16 GMT Lines: 16 In article <1992Oct27.194507.21093@news.uiowa.edu>, jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879) writes: |> From article <1992Oct27.102532.60147@cc.usu.edu>, |> by ivie@cc.usu.edu (CP/M lives!): |> > |> > Anyone planning a big bash for the PDP-5's 30th birthday? |> |> No, but someone ought to do so! Who's got a working PDP-5 to use as the |> centerpiece of the celebration? The Computer Museum has one, I don't know if it works. I have one which needs a lot of work. Someone modified it to have a real PC! [cf. previous thread about PDP-5 front panels] -- Paul Pierce prp@ssd.intel.com Intel