test-drb August 2006

test-drb@ccmp.vtda.org

216 participants
517 discussions

by ajp166＠bellatlantic.net

> >Subject: Octal > From: M H Stein <dm561 at torfree.net> > Date: Thu, 31 Aug 2006 11:13:38 -0400 > To: "'cctalk at classiccmp.org'" <cctalk at classiccmp.org> > >----------Original message(s): > >Date: Thu, 31 Aug 2006 16:14:14 +1200 >From: "Ethan Dicks" <ethan.dicks at gmail.com> >Subject: Re: Octal > >>> M H Stein wrote: >>> >>> I've found the Windows Calculator to be the most convenient >>> (nicer keyboard & display and doesn't take any desk space). >>> mike > >>I prefer 'dc', the calculator program that comes with UNIX - it does >>different radix inputs and outputs, and uses RPN, plus, I _always_ >>have a UNIX shell handy (and almost never have a real calculator or a >>Windows box in front of me). > >Well, of course you'd use whatever you like and runs in the OS of your >choice, but it's interesting to note how many people still use a "real" >calculator when there's probably one on the screen in front of them, >not to mention a spreadsheet program; every office user I visit still >has a calculator on his/her desk... Lesse, While the calc on my NT4 box has most of the right stuff it doesn't do logic (AND, OR, XOR, NOT) and if I ask for a "tape" the printer is at the other side of the room. Feh! Often I need the result when NOT at a PC. ><snip> >>I miss my old Sharp 4-banger with the flourescent digits. I have the >>parts in a bag, but it needs some serious plastic reconstruction - I >>think the plasticizer was all baked out - the case is seriously >>brittle. > >>-ethan > >That raises an interesting question: does anyone know of any substance >that actually "revitalizes" brittle plastic? None. In a few cases I used the old parts to cast new. Allison

17 years, 8 months

Octal

by dm561＠torfree.net

-----------Original message(s): Date: Wed, 30 Aug 2006 22:17:22 -0700 From: "Chuck Guzis" <cclist at sydex.com> Subject: Re: Octal >>On 8/30/2006 at 9:45 PM woodelf wrote: >>I find computer calculator programs a pain. >Depends on the calculator. I use this one all of the time and would love >to have it in a nice little handheld: >http://www.bias.at/Download/english/calcdle.htm >But it does the job right now. >Cheers, >Chuck --------Reply: Looks quite interesting, but does it do hexadecimal? Talk to Don, maybe he can whip one up for ya for a price :-) mike

17 years, 8 months

Octal

by dm561＠torfree.net

-----------Original message: Date: Wed, 30 Aug 2006 21:45:23 -0600 From: woodelf <bfranchuk at jetnet.ab.ca> Subject: Re: Octal >I find computer calculator programs a pain. That's a pretty sweeping statement; their keyboard and display are as good as the one you use every day, cut and paste is often handy for avoiding entry errors and you don't have another item on your (non-virtual) desktop; best of all, if you don't like anything out there you could presumably create your own. I am curious: what exactly is it that you don't like about them? >In fact it is hard to find a good calculator - read >nice display -- good keyboard. You don't find that >with the $5 calculator market. I'm obviously less demanding; I'm quite happy with my $1.00 calculator: nice large LCD display, full size keys and solar-powered. Cheaply made, true, but that's why it cost $1.00, and it's served me well for 3 or 4 years; if it dies I guess I'll have to bite the bullet and spend another $1.00. I for one am amazed and delighted that calculators, computers etc. can be manufactured as cheaply as they are while in general being much more efficient/useful/powerful and just as reliable (or more so) than the products of yore, which would presumably cost several orders of magnitude more if manufactured the same way today and be completely out of my reach pricewise. mike

17 years, 8 months

DATIP from clr always? (obscure unibus & pdp-11 question)

by brad＠heeltoe.com

An obscure unibus & pdp-11 question: Does "clr" always do a DATIP (i.e. read-modify-write) on all 11's? It does on my 11/44. Something tells me I've seen threads (long ago) on this and the perils of using clr as opposed to "mov #0," when talking to hardware. The rl01 bootstrap does it talking to rl11 registers, which tripped me up for a bit. -brad

17 years, 8 months

Octal

by dm561＠torfree.net

----------Original message(s): Date: Thu, 31 Aug 2006 16:14:14 +1200 From: "Ethan Dicks" <ethan.dicks at gmail.com> Subject: Re: Octal >> M H Stein wrote: >> >> I've found the Windows Calculator to be the most convenient >> (nicer keyboard & display and doesn't take any desk space). >> mike >I prefer 'dc', the calculator program that comes with UNIX - it does >different radix inputs and outputs, and uses RPN, plus, I _always_ >have a UNIX shell handy (and almost never have a real calculator or a >Windows box in front of me). Well, of course you'd use whatever you like and runs in the OS of your choice, but it's interesting to note how many people still use a "real" calculator when there's probably one on the screen in front of them, not to mention a spreadsheet program; every office user I visit still has a calculator on his/her desk... <snip> >I miss my old Sharp 4-banger with the flourescent digits. I have the >parts in a bag, but it needs some serious plastic reconstruction - I >think the plasticizer was all baked out - the case is seriously >brittle. >-ethan That raises an interesting question: does anyone know of any substance that actually "revitalizes" brittle plastic? m

17 years, 8 months

Vacuuum tube digital circuits (50 year rule)

by ajp166＠bellatlantic.net

> >Subject: Re: Vacuuum tube digital circuits (50 year rule) > From: "Ethan Dicks" <ethan.dicks at gmail.com> > Date: Thu, 31 Aug 2006 17:55:47 +1200 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >On 8/31/06, woodelf <bfranchuk at jetnet.ab.ca> wrote: >> The ads list a 12au7 for about 65 cents in 1955. In 2006 a generic 12au7 >> is about $8.00. I suspect a better deal now than 50 years ago. > >Hmm... if I leave off seconds and just go with minutes/hours, I think >I have enough. Even with modern wages, a bag full of tubes costs >enough to make me want to simplify the design. Hunt a bit I've found Vacuum tubes NOS (New Old Stock) to be widely available. The prices vary widely. To do time.. 12:59 should give you a hint. You need 3 counters only one is decade. the tens of minutes is 0..5 (/6) and hours is either /12 or /24. >The real trick, now, I guess, is how to take 60Hz mains and clock it >down to 1/60Hz with 1955 technology. You need a decade counter and a /6 counter for that, same general circuit just no disply. For simpler you can use several retriggerable monostable with time out being just longer than say 10 cycles and a second with time out of >6 cycles. At most three tubes to do that (12au7/12ax7/12at7). Back when Grumman plant-33 closed (LM project) I picked up a Beckman EPUT (events per unit time) and it was basically 5 digits of that style counter (counted to 5mhz, 8 on a good day) a time base and input circuits (Schmidt trigger). All tubes! Allison

17 years, 8 months

DATIP from clr always? (obscure unibus & pdp-11 question)

by bqt＠softjar.se

Don North <ak6dn at mindspring.com> skrev: > >Brad Parker wrote: >> > Don North wrote: >>> >> On all the discrete logic 11s and LSI11 the CLR instr does a >> > ... >> > >> > thanks! >>> >> So if your hardware can't tolerate a read access to a register, then you >>> >> can do a MOV #0,ADR instead of CLR ADR (and make a note in your code why >>> >> so some poor soul 30 years from now understands why you are doing a >>> >> non-optimal MOV #0,xxx!) >> > >> > I fixed the hardware :-) I was just curious about which machines did >> > what. >> > >> > The problem was that the two transactions are back to back and the bus >> > master keeps overnership. I was waiting for BBSY to go away... >> > >> > -brad > >The 'original' use for DATIP-DATO (vs a sequence of DATI, DATO) was to >let core memory know it did not have to do the read-restore cycle, since >a DATO was coming right away to the exact same location and would >overwrite with new data. The memory could then be a little bit faster. >With MOS memory this is not necessary. > >Some later CPUs (11/74) iirc altered all the 'normal' memory accesses to >be just DATI and DATO(B) cycles, and implemented the special sequence >DATIP-DATOB for the ASRB instruction to act as the atomic memory >interlock. But I digress... > >Don I don't remember for sure here, but can't you have other times where several transactions come back to back without the bus being released? I really should look into the documentation, unfortunately it's not where I am right now. As for the 11/74, it didn't modify the interpretation of the Unibus transactions, since the memory isn't on the Unibus. :) The 11/7x memory bus do have a transaction that keeps the location locked until a write have occurred however. Not used in the 11/70, but the 11/74 uses that. (Obviously.) It's documented in the memory subsystem manual for the 11/70. The only instruction using that bus transaction is the ASRB howewer. Not sure if the 11/84 might have redefined the Unibus somewhat. I remember that there is some note about possible problems with some Unibus devices in an 11/84, but I think it has to do with timing during a bus reset. Wish my memory was more accurate. :) Johnny

17 years, 8 months

"File types"

by THX1138＠dakotacom.net

Hi, When did the notion of "file types" creep into computing? Hmmm... poorly phrased. How about: "When did the notion of file *associations* (?) creep in?". I don't seem to recall having any problem typing: qedx myfile.mp3 or even: qedx a.out (et al.) I know Apple had "file creator" attributes that were semi-hidden (i.e. not part of the file *name*). Is the concept of a "file extension" an outgrowth of the 8.3 naming scheme? Or, does it have its roots further back? Is there any rationale for this sort of an implementation? Or, just one of convenience (i.e. "there was no other space in the dirent to store this stuff so we came up with the idea of just bastardizing the name space to accommodate it"). Since I am not fond of Hungarian notation and consider this just another variant (precursor) thereof, I wonder why it persists? Has Apple abandoned the "hidden" file creator attributes of earlier MacOS in newer OS's (e.g., OS X)? Or, have they bowed to user pressure and implemented a "me-too" scheme?

17 years, 8 months

"File types"

by mtapley＠swri.edu

At 12:03 -0500 8/29/06, Don wrote: >IMO, this was a mistake. It forces the OS to know too much >about the applications that run on it -- instead of being a >resource manager. I.e. it should implement mechanisms, not >policy. There is at least one reason this may not be a mistake in all contexts. If the OS knows something about the files, and about the applications available, it can help me out by connecting the two (or by notifying me that the needed application is not available). That allows me to double-click on a .jpeg file and have a jpeg viewer launched automatically by the OS to open that file. The alternative is of course for me to find my own jpeg viewer, launch it, and then open the same file. The advantages here are that I'll get the *right* jpeg viewer, the OS can be much simpler, and the file can be smaller and named with greater flexibility. File type information could be imbedded in the name (.3), in a "file information" block a la MacOS-Classic, or inside the file itself. I can even imagine an OS with a "guess-the-application" facility, which is actually an application itself that guesses which other application to launch and pass the file to based solely on the file's content or context (though I can imagine that facility failing >from time to time). I think any of these strategies could (and do?) work. I'm not sure that selecting one over the other is a mistake, just a choice adapting the OS to a different function. Some rely more on the user's input, some take more machine resources and are less transportable. -- - Mark Cell Phone: 210-379-4635 office: 210-522-6025

17 years, 8 months

board found

by rtellason＠verizon.net

I looked in a box here that I hadn't looked into in a while, and found this board... It's _not_ ISA, PCI, or any of those formats. Says on the top "Panther EDAC Memory Board". There's also what appears to be an NCR copyright on it, 1993. There are a half dozen big chips across the bottom where the edge connectors are, 5 of them marked VLSI and one NCR with a 1990 copyright date on it, and eight SIMM (?) sockets, but these are not your standard ones -- if I take a 72-pin SIMM and line it up with the notch with one of the occupied sockets on the board, I have 3-4 pins left over (on the part on the board) at each end. Four of the sockets are occupied. The two in the middle that aren't are labeled "Bank-1/3 Byte-2" and "Bank-1/3 Byte-1", I can't see the markings for the other ones and don't want to pop these SIMMs out at the moment. Near the center of the board are four other sockets, with a chip in one of them, looks almost like a SIP but the pins are in two rows, real close together, coming out of the same side of the package (what do you call this?) and the part in the one socket that's occupied is marked "Toshiba" and "TC5117400Z-60". There are also 3 barcoded stickers one of which bears the date "Oct 31 1994" in the middle of two barcodes. This *may* belong with that NCR tower that went out of here a while back, I don't know for sure. Anybody know what it is? Anybody maybe have a use for it? -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, a critter that can be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

17 years, 8 months

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test-drb August 2006