test-drb April 2020

test-drb@ccmp.vtda.org

142 participants
114 discussions

ISO: Documentation for Interphase SMD 2181 disk controller

by derschjo＠gmail.com

Subject line says it all. The Lambda uses this as its disk controller and it's looking like the one in mine needs some debugging. There doesn't seem to be any documentation for this controller out there. There are docs for the Interphase SMD 2180 on Bitsavers but it appears to be a very different board. Thanks! Josh

4 years, 3 months

State of New Jersey needs COBOL programmers

by commodorejohn＠gmail.com

> From: Neil Thompson <albiorix at gmail.com> > > I'm convinced that Dijksta (and anyone else who came out with similar > comments were full of horseshit. In my opinion, it's the ability to > translate a real world "thing" into an algorithm that is the essense of > programming, and anyone who has managed to learn (particularly on their > own, as many of us did) that ability has learned something that transcends > the language (or tool) you use to implement the algorithm. There's definitely truth to this. The main thing that makes a good programmer isn't memorization of language features or syntax, it's good mental organization and thinking habits; the ability and practice of really *thinking through* the steps involved in solving a problem, building a solid mental model of the relevant data structures and algorithms, and then breaking those down into component steps until one arrives at a suitable representation in native-language operations. If someone has a good understanding of that, they can apply it (with varying amounts of blood, sweat, and tears) in any language; if they don't, there's no language in the world that can impart it to them (no matter *what* the flavor-of-the-decade Savior Of All Programming Forever is - "Try Swift! It's the new Pascal!") *That said,* there are definitely some languages that are more conducive to building these habits than others (and, within each group, many that emphasize different aspects more or less strongly.) I can't speak to COBOL as I've never had cause to get any experience with it, but I would say that BASIC (as in, the old-school, unstructured BASICs of the Bad Old Days) really does teach you a bunch of habits that you end up needing to un-learn as soon as you start working with better languages (not even *newer* languages - ALGOL and Lisp both predate it.) Line-#-and-GOTO programming imposes the same burden of bookkeeping and space-management on the programmer as direct machine-code monitor hacking and the most primitive assemblers, but without any rational explanation as to why, so that any novice attempting to create a program of any real complexity ends up being instilled with a superstitious dread over the ludicrous non-question of where to put things - do I space statements N numbers apart? What if I need to add more than N-1 intervening statements later!? Should I place my subroutines on even 1000s for easy reference? Will the line numbers even go high enough!? - the lack of scoped/local variables or any parameter-passing mechanism for GOSUB makes any non-trivial modularization nearly impossible, and the READ/DATA structure is just flat-out demented. And all that mental exhaustion *before* the newbie even gets to the *real* challenges of learning to program! Now, Dijkstra was a self-important ponce given to wild all-or-nothing proclamations and manifestos (manifestes? Manifesti?) and even if we give him the benefit of the doubt and assume that his statements quoted here were meant tongue-in-cheek they're still pretty ridiculous. And God knows the Appointed Language Messiah in that great holy war, Pascal, was its own special breed of Hell for novices and experts alike (array size as type qualifier? Just kill me now...) And it's definitely true that plenty of people can and did learn to program in BASIC and still went on to learn better and do Good Things down the line. But there absolutely are such things as bad programming languages.

4 years, 3 months

cctalk Digest, Vol 67, Issue 6

by athornton＠gmail.com

On Apr 6, 2020, at 10:00 AM, cctalk-request at classiccmp.org wrote: > > They play with the > pennies to discover that they can roll around, and learn that they're not > food or nasal suppositories, I was with you up till here, but wait, what? I?m one of those kids who was just the right age. Five years older and I would have been in the Car Club, and would have ended up being a damn good mechanic without a lot of career opportunities. Five years later and not every damn computer on the planet would have come with a BASIC interpreter in ROM and who knows what my tinkering instinct would have led to. But I, born in 1971, had an Atari 2600 and its BASIC programming cartridge, and in the fall on 1982 I got a VIC-20, and sometime in 1983 my parent bought me an Apple //e. So I did grow up with Microsoft BASIC as my first language, and, sure, it doesn?t lend itself well to structured programming, but then when I wanted to know ?well how do you do _that_?? I ended up in 6502 assembly, and picked up P-System PASCAL and Logo along the way. Then in the summer of ?89 I interned in a physics department, and got OK at Turbo Pascal and sort-of-vaguely-able-to-write C. College brought REXX on (IBM VM/CMS; I didn?t get an Amiga until the 2010s, well after its relevance) and Perl and Scheme and SPARC assembly, and grad school (both for irrelevant degrees: Ancient Mediterranean Civilization and History?but wait, there?s a footnote) 680x0 assembly and Java. (The footnote is, well history of computing, so I got a lot of deep-dive stuff into other languages and architectures.) Since then, whatever I needed to learn when I needed to learn it. I?ve programmed COBOL for money, which has joined the ranks of things I?m not super-proud to have done for money but hey it paid the bills when I needed it. Since then?Python, C, Go, TypeScript, whatever was needed. These days it?s mostly Python. But really what it was was that I was lucky enough to be in that small age window where computers were, one the one hand, something middle-class families could afford while still being capable of doing cool things, and on the other hand, simple enough that a smart adolescent could pretty much understand them more-or-less in their entirety. Adam

4 years, 3 months

State of New Jersey needs COBOL programmers

by boris＠summitclinic.com

At 16:12 05-04-20, you wrote: >On 4/5/20 6:28 PM, geneb via cctalk wrote: >>On Sun, 5 Apr 2020, Neil Thompson via cctalk wrote: >> >>>I'm convinced that Dijksta (and anyone else who came out with similar >>>comments were full of horseshit.? In my opinion, it's the ability to >>>translate a real world "thing" into an algorithm that is the essense of >>>programming, and anyone who has managed to learn (particularly on their >>>own, as many of us did) that ability has learned something that transcends >>>the language (or tool) you use to implement the algorithm.? When I first >>>started programming professionally, we had "programmers" (or sometimes >>>designers) who specified the algorithms and "coders" who implemented them. >>>That never worked well >>Yep.? You can write horrible code in /any/ language. ;) >>BTW, I scanned & uploaded this last week.? Oddly relevant. >>https://archive.org/details/cobolcodingform > >I still have lots of them. And Printer Output Forms. And Fortran >Programming Forms. And all kinds of other Programming forms. And >Flow Chart Forms. You know all that stuff we actually used to >engineer programs before the software engineers came along and said >we were all doing wrong. > >bill Ran into a bunch of my FORTRAN programs from over 50 years ago as well as the obligatory flowcharts I would do first before writing a single line of code. Code written in pencil so could erase errors and only then would I use a keypunch for final version. Also a few FORTRAN coding forms. Back then, with sometimes a 48 hour delay between submitting my card deck and getting program output, it was well worth spending an hour or two to print out contents of cards and carefully check that there weren't missing commas and or other errors that would mean correcting the stupid mistake and resubmitting ones card deck. Never got into COBOL as my main interest was real-time computing and so next step up was access to PDP-8 which had FOCAL and quickly learned that programming in assembler was the way to go. Still like assembly language programming and suspect my early experience of learning to code in an environment where there wasn't really a dividing line between software and hardware (people would build custom boards for PDP-8's/PDP-11's to speed up data acquisition) that the biggest change I made in my programming style was to switch to VB as it allowed me to easily create the graphical interface I needed but still let me link to C or Assembler routines in my VB6 code until windoze became too locked down to be of any use. Still haven't got all my VB6 programs running under Wine on Linux but at least Linux has FORTRAN and C. Part of what I've noticed is that I can't sit down at a keyboard and write code (as one is supposed to do nowadays) and it turns into a total mess. I still use flowcharts when I'm dealing with tricky code and the nice thing about flowcharts is that one can easily create a hardware state machine from them. Was nice in 1970's, but now a Propeller chip, even using interperted Spin code, works far faster than the TTL state machines I used to make. Other paleo-programmer related deficits include being totally unable to use RDB and still make use of linked lists and hash tables to create my databases as have been doing this for 50 years. Software Tools was probably the most important book I read in 1983 as it got me out of my rut of writing a massive FORTRAN program to do a specific task that I'd have no idea how to modify even 6 months later to small useful tools that could be strung together. Back then engineers I worked with would have total disdain for Comp-Sci types who would still be working out their code indentation scheme while we would already be using a quickly written throwaway program to perform a particular task. The other thing I should bring up is that my wife is after me to get rid of a lot of my old books. While rumaging through the attic of my shop found boxes of old computer books which I'd like to keep but have been told that if I haven't looked at them in 15 years that it's unlikely I will in future. Will check in see if some of them have been scanned onto bitsavers or other sites but have 68000 programming books, 6502 and other microprocessor related books as well as lots of Mac books when I just had to get into the guts of a Mac to do what I wanted. Have a number of PDP-11 Unibus cards which likely won't use and will have to get all of that sorted out. Once have a list of what I've got will post it on my web site. I live in Kamloops, BC if there's anyone on this list who lives close by who's interested.

4 years, 3 months

OT: Weller soldering irons

by pete＠dunnington.plus.com

A few hours ago I started looking at three "smart" light switches that need LEDs replaced, and switched on the soldering iron, and ... nope. It's a Weller WP80 and it seems the sensor in the heating element has died. I discovered that only after resetting and then dismantling the control unit to check it out with a DVM, of course. Clearly I need either a new WP80 element, or a new soldering iron. I could get a WSP80 for far less than the cost of a new element for the WP80, but I'd get the element faster. So which, if any, is the better iron? What would you guys do? I begrudge paying UKP 92 for a new element. That's the cheapest I could find -- /half/ the most expensive price -- but just seems ludicrously extortionate for what amounts to a piece of swaged stainless steel tube with a short length of resistance wire and an even shorter length of thermocouple wire inside it. I could buy a whole new solder station with more bells and whistles, albeit of a "lesser brand", for less. -- Pete Pete Turnbull

4 years, 3 months

Prime documentation

by drb＠msu.edu

For those interested in playing with Jim's emulator, a few resources: Bitsavers has some doco and bits: http://bitsavers.org/pdf/prime/ http://bitsavers.org/bits/Prime/ I have been assembling what I hope will be the definitive Prime info site. It's not complete, but contains manuals scanned by, among others, AEK and Jim Wilcoxson, as well as material from my Prime-using past, etc. I have more documentation and software to add as I have time. https://sysovl.info/reference_prime.html Of particular use might be this writeup on installing PRIMOS Revs 22 or 23 on the emulator. It's set up for the old demo version of the emulator, so needs a fair amount of updating, but may help get you started. I'll work on it soonish. https://sysovl.info/reference_prime_drb_installing_primos.html De

4 years, 3 months

pdp11/05 key?

by jnc＠mercury.lcs.mit.edu

From: Tom Uban > Does anyone have information on having a replacement PDP-11/05 key made? Google is your friend; here: https://gunkies.org/wiki/PDP-11/05#Keys I don't recall if there's anough info there to create new keys without an original to copy. At one point I made a run of copies (after posting a call here); I suppose I could do so again. Noel

4 years, 3 months

APL-11

by mark＠matlockfamily.com

>According to the Ref Manual, that's the one I was looking for. >Now to mount the RL on RSTS and see what it takes to build it >there. I'll let the list know how I make out in case someone >else is interested. > >bill The RL02 image is RSX Files-11, and I?m not sure if you can mount that with RSTS. I could move it to a RT-11 formatted RL02 or if your RSTS system is on HECnet I can put it where you could get it that way. I looked for the original DOS-11 formatted DEC distribution tape but can?t find it at this time. Let me know if you need anything. Mark

4 years, 3 months

Identifying Machine for DEC Memory

by robert.jarratt＠ntlworld.com

I mistakenly bought some memory thinking it was for a VAXstation 4000 VLC. It turns out that it isn't. It physically fits a VAXstation 4000 Model 60, but putting it in that machine the machine fails to power up. The part number is 50-19464-02, and I am unable to identify what machine it works in. Can anyone tell me where to find out? Thanks Rob

4 years, 3 months

ISO: Cipher F880 tape drive, Fujitsu Eagle disk drive

by derschjo＠gmail.com

I'm working on restoring an LMI Lambda, which is missing both its tape drive and its disk drive. If anyone has a Cipher F880 9-track drive or a Fujitsu Eagle SMD drive, drop me a line. Be nice if they were in working condition, but so long as they're repairable I can work with 'em. Thanks! Josh

4 years, 3 months

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test-drb April 2020