[cctalk] Re: What's the going rate for 80286?
On 2024-09-18 12:29 p.m., Fred Cisin via cctalk wrote: On Wed, 18 Sep 2024, John via cctalk wrote: Dunno, what does a box of Cracker Jack cost these days...? I checked; Amazon has Cracker Jack THREE boxes for $4.53 That's sold by a third party, but fulfilled by Amazon. I've been told that the current prizes are stickers to unlock games on their website. They haven't had microprocessors as prizes in a long time. The switch to games saved money, and protected them from liability lawsuits for choking on a prize (an 80286 might do some damage if swallowed) So far, Arduinos are still more expensive than stickers. But, keep waiting. -- Grumpy Ol' Fred ci...@xenosoft.com The price is 25 cents, or $2,500 when you need one. I was more a lucky elephant person. Ben.
[cctalk] Re: auction starting in 50 minutes
On 2024-09-11 2:18 p.m., Sellam Abraham via cctalk wrote: On Wed, Sep 11, 2024 at 11:49 AM ben via cctalk wrote: Now even a TTL version. https://hackaday.io/project/190345-isetta-ttl-computer/log/232670progress-of-new-pcb That link is bad. It is not good. The link worked fine before the copy and paste. :( google 'isetta-ttl-computer' works But really, do have room for more computers:) It is the lack of cases that sadly are limited. People generally 3D print their own nowadays. And I imagine you can still buy generic enclosures of all sizes from Amazon or eBay or Ali Baba or whatever. There are services on line for front panels and they often do cases. I was hoping a for ham radio guy type service as well. Sellam
[cctalk] Re: auction starting in 50 minutes
On 2024-09-11 8:43 a.m., Sellam Abraham via cctalk wrote: 53 On Tue, Sep 10, 2024, 11:03 PM Mark Linimon wrote: Next week there will be 50 of them o. Ebay for this price. (looks around the room) Make that 52. mcl But as the ratio of buyers is a complex number. It is often in the imaginary realm. -200j,3 is my guess. The number of retro 6502/z80 projects seem to be on the rise. Now even a TTL version. https://hackaday.io/project/190345-isetta-ttl-computer/log/232670progress-of-new-pcb It is the lack of cases that sadly are limited. Ben.
[cctalk] Re: MS-DOS
On 2024-08-17 1:46 a.m., Peter Corlett via cctalk wrote: On Fri, Aug 16, 2024 at 11:42:01PM -0600, ben via cctalk wrote: On 2024-08-16 12:11 p.m., Peter Corlett via cctalk wrote: [...] From what I can tell of a casual peruse of the documentation of CP/M-68K and CP/M-86, they support the full address space of 4GiB and 1MiB respectively. This is kind of obvious on the m68k since why would they artificially limit it, but on x86 it's less obvious because they could have restricted changing the segment registers. CP/M-86 *also* supports an "8080 model" with CS == DS == ES, presumably to ease quick ports of 8080 code through source-to-source translation. I picked up a bare bones 68000 single board computer, and the only OS is is a hacked CPM/68000 version in C. Any guess what compiler/assembler was used back then and on what host? Does one have sub directories? Classic CP/M does not have subdirectories, and instead has 16 "user areas", which are of limited utility. But of course the 68000 is far more powerful than the x80, and the popular 68000 platforms all had hierarchical file systems, so one might wonder if support had been added since it would be a bit silly to have a machine which can access 16MiB of memory but is still limited to a flat file system which can only hold a few tens of files. Source code to CP/M-68K can be found at <http://www.cpm.z80.de/source.html>, so I downloaded them to have a look. I looked at the 1.0x sources as they are a ZIP file of conventional text files, whereas the later versions are ZIP files of disk images which are harder to read without a running CP/M system. The bulk of the code is written in K&R C, with some assembly for things such as exception handlers which can't be written in C or performance-critical such as floating-point. The source code is for BDOS plus utilities, notably including a C compiler and assembler. There are various other file droppings which give a hint of what's going on here. From a very rough perusal of the source code, these are my tentative answers to your questions: The sources include a C compiler and assembler, and the readme says they are "ALCYON Compiler/Assembler/Loader". So this is probably what everything was built with. They are cross-platform, so long as you are using a common-or-garden VAX or PDP-11 running Unix or VMS such as the one we all had in our childhood bedrooms back then, VERSAdos (no, me neither), and fortunately also natively on CP/M-68K. The file droppings suggest that Alcyon Corporation probably cross-compiled it on VMS. I can't find any likely-looking code in the BDOS sources pertaining to subdirectories such as file types or attribute bits indicating a directory entry is actually a subdirectory rather than a regular file, so I think CP/M-68K still has a flat file system after all. The source for 1.1 comes as 14 256,256-byte disk images, suggesting a lot of disk-swapping to build it natively. I picked up two 68K systems, a cheap one (68000) and better one (6809 ops 68030) and it has cp/m 68k A: compressed in ROM. I am now just waiting for 512mb CF cards. The file system is still flat, but you can have drives b: to e: ?: ?: still is ok for my use. They have microemacs, but finding the keybindings to cpm68k may be trickey.
[cctalk] Re: Antonio's call for donations (was LCM auction)
>> By the way, the earth is round... > > I'm glad we can agree on this. Of course the Earth is round. > > It's also hollow.Oh it is a donut!> > To try and turn this thread around: I'm looking to make an extended > memory controller for my pdp8/L. I've got a wire wrap backplane and > enough cards to make it work but I've never done wire-wrap on this sort > of scale. > > I've got an old Radio Shack Wire wrap tool and a lot of wire. Is there > any sites that discuss how to do reasonable wire-wrapping? I think back then they used different wire wrap sized wire on the back planes
[cctalk] Re: LCM auction
On 2024-08-30 12:00 p.m., Don Stalkowski via cctalk wrote: Fred Cisin wrote: We have our own non-theological religious wars, such as vi vs emacs. TECO Don Does anybody use that any more?
[cctalk] Re: LCM auction
On 2024-08-29 1:53 p.m., Antonio Carlini via cctalk wrote: On 29/08/2024 17:27, Douglas Taylor via cctalk wrote: The solution is right in front of us. One of us here has to become a multi-billionaire and create a museum to save all this stuff! Let the fighting and bickering begin! Any ideas on how to become a billionaire? Let me start by saying this is my idea, I thought of it first and I'm declaring copyright on it. If everyone on this list sends me just 0.5% of their total wealth, I promise to try really hard to preserve some retro computing stuff. Honest. USDC would be best please, I'll set up a wallet as soon as the first donor steps up :-) Antonio MONEY SUCK PROGRAM ARE YOU SURE! (Y/N)
[cctalk] Re: LCM auction
On 2024-08-29 11:59 a.m., Fred Cisin via cctalk wrote: Any ideas on how to become a billionaire? For a few decades, we have been saying that "We must do whatever it takes to make Bill Gates into a millionaire." it is called TAX!
[cctalk] Re: LCM auction
On 2024-08-29 10:27 a.m., Douglas Taylor via cctalk wrote: The solution is right in front of us. One of us here has to become a multi-billionaire and create a museum to save all this stuff! Let the fighting and bickering begin! Any ideas on how to become a billionaire? Doug Find a billion fools with money. :) While most of it was luck, and the right place at the right time, Apple , Microsoft, Intel & Zilog and the 6502* it still took a lot of work to get there in the early days.Only later did they get rich. Ben. PS: * Had to say the 6502, or a cult with torches might show up at my door.
[cctalk] Re: MS-DOS
On 2024-08-16 12:11 p.m., Peter Corlett via cctalk wrote: CP/M was effectively limited to 64KiB because it had no traction outside of the 8080/Z80 which had a 64KiB address space. To go beyond that limit on those CPUs involves paging, and some platforms did indeed use paging for RAM disks and to move some OS out of the way to leave more RAM for programs. But as far as programs are concerned, 64KiB is the limit unless they happen to be platform-specific and know how to handle the paging. From what I can tell of a casual peruse of the documentation of CP/M-68K and CP/M-86, they support the full address space of 4GiB and 1MiB respectively. This is kind of obvious on the m68k since why would they artificially limit it, but on x86 it's less obvious because they could have restricted changing the segment registers. CP/M-86 *also* supports an "8080 model" with CS == DS == ES, presumably to ease quick ports of 8080 code through source-to-source translation. I picked up a bare bones 68000 single board computer, and the only OS is is a hacked CPM/68000 version in C. Any guess what compiler/assembler was used back then and on what host? Does one have sub directories?
[cctalk] Re: A little off-topic but at least somewhat related: endianness
On 2024-08-16 8:56 a.m., Peter Corlett via cctalk wrote: On Thu, Aug 15, 2024 at 01:41:20PM -0600, ben via cctalk wrote: [...] I don't know about the VAX,but my gripe is the x86 and the 68000 don't automaticaly promote smaller data types to larger ones. What little programming I have done was in C never cared about that detail. Now I can see way it is hard to generate good code in C when all the CPU's are brain dead in that aspect. This makes them a perfect match for a brain-dead language. But what does it even *mean* to "automaticaly promote smaller data types to larger ones"? That's a rhetorical question, because your answer will probably disagree with what the C standard actually says :) I have yet to read a standard, I can never find, or afford the documentation. I used Microsoft C for DOS,and had that as standard model as well as 8088 cpu. C for the most part was 16 bit code, with a long here and there. I use Pelles C for windows version 8, since windows dropped 32 bit programs. As a hobby project, I am building a CPU of some size 24 bits or less. Tried a FPGA card for the last decade, but the internal routing kept screwing up. Now that we got cheap PCB's from china, I had 2901 Bit slice machine almost working. I can read/write from the front panel,but programs don't work. Software emulation in C under windows works only as prototype code. I picked up a cheap 68K board since it has no MMU and just static ram,I can use that to emulate my hardware design. Now I need to get a cross assembler and c compiler for the 68K. When I get the C emulator code working, I can later write a faster version in assembler. When I started this project any software my I could need would be written in the small C subset of C, or a revise a 16 bit C compiler source code. Now, what kind of badly-written code and/or braindead programming language would go out of its way to be inefficient and use 32-bit arithmetic instead of the native register width? The problem is the native register width keeps changing with every cpu. C was quick and dirty language for the PDP 11, with 16 bit ints. They never planned UNIX or C or Hardware would change like it did, so one gets a patched version of C. That reminds me I use gets and have to get a older version of C. I'm sure you can "C" where I'm going here. `int` is extremely special to it. C really wants to do everything with 32-bit values. Smaller values are widened, larger values are very grudgingly tolerated. C programmers habitually use `int` as array indices rather than `size_t`, particularly in `for` loops. Apparently everything is *still* a VAX. So on 64-bit platforms, the index needs to be widened before adding to the pointer, and there's so much terrible C code out there -- as if there is any other kind -- that the CPUs need hardware mitigations to defend against it. I still using DOS c compilers,for small C. Int just has one size - 16. No longs, shorts or other stuff. DOSBOX-X is nice in that I can run dos programs or windows command line programs. It's not just modern hardware which is a poor fit for C: classic hardware is too. Because of a lot of architectural assumptions in the C model, it is hard to generate efficient code for the 6502 or Z80, for example. or any PDP not 10 or 11. I heard that AT&T had C cpu but it turned out to be a flop. C main advantage, was a stack for local varables and return addresses and none of the complex subroutine nesting of ALGOL or PASCAL. But please, feel free to tell me how C is just fine and it's the CPUs which are at fault, even those which are heavily-optimised to run typical C code. A computer system, CPU , memory, IO , video & mice all have to share the same pie. If you want one thing to go faster, something else must go slower. C's model is random access main memory for simple variables and array data. Register was for a simple pointer or data. Caches may seem to speed things up, but they can't handle random data (REAL(I+3,J+3)+REAL(I-3,J-3)+REAL(I+3,J-3)+REAL(I-3,J+3)/4.0)+REAL(I,J) I will stick to a REAL PDP-8. I know a TAD takes 1.5 us, not 1.7 us 70% of the time and 1.4 us the other 30%. Real time OS's and CPU's are out there, how else would my toaster know when to burn my toast. Only knowing the over all structure, of a program and hardware can one optimize it. Ben.
[cctalk] Re: A little off-topic but at least somewhat related: endianness
On 2024-08-15 7:46 p.m., Mike Katz wrote: That is the reason for the stdint.h file. Where you specify the width of the variable in bits Looks like a useless file to me. I never liked any the standards made to C after K&R. Seems more driven by the latest crappy hardware intel makes, than a language designed by people who use the product. C++ or JAVA never made sense because every class is too different from any other object.Don't say how windows are a good example of object, they are foobar-ed from the start as they deal in pixels, rather than a fractional screen display.Text windows worked under DOS.something easy to program. I don't want write a whole operating system to use modern software like windows. Grumpy Ben, trying to find a embedded C compiler for the 68000. PS: Perhaps if they had good textbook for C and the different standards I might view modern C with less distrust.
[cctalk] Re: LCM auction
On 2024-08-15 7:52 p.m., cz via cctalk wrote: True, but back then things were designed to fixed and tested. Sure, and they can still be fixed, transistors are quite common. But after repairing a pair of pdp8/L's, and a pdp8/I I really have to say it's a bit of a serious job. And the 10 is like. a billion times more stuff This list needs a good machine shop as well, for older I/O devices. Or a least a parts list of spares. Old computers I think had better doc's than today, that had real information, Ben.
[cctalk] Re: LCM auction
On 2024-08-15 7:39 p.m., cz via cctalk wrote: Eh, it will go for what it goes. Try and keep in mind how tough it was to keep a 1010 running in 1995. Then add 30 years to that. The thought of tracking down a bad flip flop on a thousand flip chip boards really makes me think "yow". True, but back then things were designed to fixed and tested. CZ
[cctalk] Re: A little off-topic but at least somewhat related: endianness
On 2024-08-15 6:46 p.m., Fred Cisin via cctalk wrote: When I was teaching C, it was sometimes quite difficult to help students who had firm assumptions about things that you can'r assume. Such as the sequence of operations in the multiple iterations examples that we both used. I tried desperately to get them to do extensive commnets, and use typecasts even when they could have been left out. I keep assuming C is still 16 bit K&R. Software tends to depend on the fact bytes are 8 bits, and every thing a 2,4,8 bytes wide and the newest hardware/software/underwear^H^H^H^H^H^H^H is the best. PL/I tried to fit data types, to have variable width that I think was a good idea. foobar Binary:unsigned:36 bits:mixed endian,volatile,module blah,dynamic array x y z. It least then you know what foobar does. HUMBUG foo, not so clear. Ben, still thinking 18 bit computers are just the right size for personal use, and some day I will have hardware.
[cctalk] Re: A little off-topic but at least somewhat related: endianness
On 2024-08-15 11:00 a.m., Paul Koning via cctalk wrote: The short answer is "it's historic and manufacturers have done it in different ways". You might read the original paper on the topic, "On holy wars and a plea for peace" by Danny Cohen (IEN-137, 1 april 1980): https://www.rfc-editor.org/ien/ien137.txt Not reading the paper, I would say it is more the case having short data types (little) and FORTRAN packing 4 characters in word (big). I don't know about the VAX,but my gripe is the x86 and the 68000 don't automaticaly promote smaller data types to larger ones. What little programming I have done was in C never cared about that detail. Now I can see way it is hard to generate good code in C when all the CPU's are brain dead in that aspect. char *foo, long bar; ... foobar = *foo + bar is r1 = foo r3 = * r1 r2 = bar sex byte r3 sex word r3 r4 = r3 + r2 foobar = r3 what I want is bar = * foo + bar nice easy coding. And yes, different computers have used different ordering, not just characters-in-word ordering but bit position numbering. For example, very confusingly there are computers where the conventional numbering has the lowest bit number (0 or 1) assigned to the most significant bit. The more common numbering of 0 for the LSB gives the property that setting bit n in a word produces the value 2^n, which is more convenient than, say, 2^(59-n). Real computers are 2^36 from the 50's. Big iron is the 60's. :) paul
[cctalk] Re: MS-DOS
On 2024-07-30 2:55 p.m., CAREY SCHUG via cctalk wrote: I don't think anaybody has reposted this one on this thread. Microsoft release Windows CE, which bombed Then Windows ME, another bomb Finally Window NT, a moderate success So they combined them but still can't get windows CEMENT to complete the boot process. ...or something like that. There's a tugboat down by the river, don't you know Where a cement bag's just a-drooping on down Oh, that cement is just, it's there for the weight, dear Five'll get ya ten, ol' Gates's back in town --Carey Ben
[cctalk] Re: MS-DOS
On 2024-07-29 10:09 p.m., Fred Cisin via cctalk wrote:
On Mon, 29 Jul 2024, Rod Bartlett wrote:
I found Tim Peterson's old blog a while back which contained some
interesting tidbits about the history of DOS from the original author.
http://dosmandrivel.blogspot.com/
I did find one unimportant error,
He said that DOS 1.10 supported both double sided, and 9 sectors per track.
That may have been what he wished for, but I'm pretty sure that what
Microsoft actually released was DOS 1.10/1.25 supported double sided 8
sectors per track (up from single sided in DOS 1.00),
(SOME OEM versions of 1.25 support 8" disks!)
and DOS 2.00 supported 9 sectors per track (Plus enormous other major
changes, such as the "file handle" API, added to the existing "FCB" API.
--
Grumpy Ol' Fred ci...@xenosoft.com
2.0 was better but not quite a finished product.
Xenix...
It planned over time to improve MS-DOS so it would be almost
indistinguishable from single-user Xenix, or XEDOS, which would also run
on the 68000, Z8000, and LSI-11; they would be upwardly compatible with
Xenix, which Byte in 1983 described as "the multi-user MS-DOS of the
future". Microsoft's Chris Larson described MS-DOS 2.0's Xenix
compatibility as "the second most important feature".] His company
advertised DOS and Xenix together, describing MS-DOS 2.0 (its
"single-user OS") as sharing features and system calls with Xenix ("the
multi-user, multi-tasking, Unix-derived operating system"), and
promising easy porting between them.
[cctalk] Re: Relay computers
On 2024-07-23 1:31 p.m., Paul Koning via cctalk wrote: On Jul 23, 2024, at 2:09 PM, Gavin Scott wrote: On Tue, Jul 23, 2024 at 7:11 AM Paul Koning via cctalk wrote: It's interesting that the designers of ARRA spoke about what they did, and were quite honest about their mistakes. Quite refreshing. Unfortunately that narrative is in Dutch: "Computers ontwerpen, toen". https://ir.cwi.nl/pub/13534/13534D.pdf One of these days I should finish my translation of that lecture. ChatGPT 4o did a passable job it looks like. Very much so. Comparing it with my draft translation I'd say it is quite good, much better than I'm used to from mechanical translations. paul A very good read. Young,brave and and wiling to try new things.
[cctalk] Re: Relay computers
On 2024-07-23 12:09 p.m., Gavin Scott via cctalk wrote: On Tue, Jul 23, 2024 at 7:11 AM Paul Koning via cctalk wrote: It's interesting that the designers of ARRA spoke about what they did, and were quite honest about their mistakes. Quite refreshing. Unfortunately that narrative is in Dutch: "Computers ontwerpen, toen". https://ir.cwi.nl/pub/13534/13534D.pdf One of these days I should finish my translation of that lecture. ChatGPT 4o did a passable job it looks like. Real .txt files have LF's and CR's.
[cctalk] Re: WTB: Signetics 2519 .. (Apple I components)
On 2024-07-22 8:41 p.m., Ethan Dicks via cctalk wrote: On Mon, Jul 22, 2024 at 9:05 PM Igor via cctalk wrote: Me and my buddy are building an Apple I replica, for now successfully. Recently we have tested the video signal :) However, we are having big problems (as you can imagine) with finding Signetics 2519 chips. I know many ordered them in bulk, so I would be thankful for any help (we have US address) or information. If more than one 2519B pop up for less than the crazy eBay prices, I'm interested. I have a Willegal Apple 1 board that I am still sourcing parts for (esp 2519B and 2504/1404) I am not worried about date codes or exact package styles or markings (N vs P etc.) I just want it to work.In the short term, I'm definitely willing to consider a board with 6x4557 programmable chip registers, but that still leaves the 8-pin shift registers. -ethan You can't find lose parts, but you still seem to be able to find kits https://unicornelectronics.com/Apple1/apple1.html Ben.
[cctalk] Re: the 1968 how to build a working digital computer
On 2024-07-22 7:06 p.m., Fred Cisin via cctalk wrote: Besides slide rules, etc. If you have an analog computer consisting of a 5 gallon bucket, and a 3 gallon bucket, and plenty of water available, What are the steps for a PROGRAM to get a result of 4 gallons of water in the 5 gallon bucket? Step 1: Get a cowboy with a 10 gallon hat.:)
[cctalk] Re: the 1968 how to build a working digital computer
On 2024-07-21 6:43 p.m., Paul Berger via cctalk wrote: I would say digital a common relay has two states open or closed, when you energize the coil it draws in the armature which will open or close the relay's contacts. Konrad Zuse built his first digital computer using largely relay logic in 1940, but his work was not widely known until well after WWII due to him working mostly by himself in Germany. He was aware that vacuum tubes could be used as logic elements, even having one demonstrated to him by a friend, but stuck with relays as they where easier to obtain. All of Zuse's machines are digital. I find his mechanical memory most interesting. Paul. Quote on the Z1 There is a replica of this Model in the Museum of Traffic and Technology in Berlin. Back then it didn't function well, and in that regard the replica is very reliable — it also doesn't work well. — Konrad Zuse Ben.
[cctalk] Re: the 1968 how to build a working digital computer
On 2024-07-21 8:29 a.m., Sellam Abraham via cctalk wrote: I'm pretty sure the book included "Working" in the title because who wants to build a non-working computer? Also, mechanical analog computer = slide rule :) Sellam A working computer, is one that makes money? Ben.
[cctalk] Re: the 1968 how to build a working digital computer
On 2024-07-20 10:41 p.m., Tony Duell via cctalk wrote: On Sun, Jul 21, 2024 at 3:08 AM Steve Lewis via cctalk wrote: What I meant was that in the title of the book they use "digital computer" and I wonder if there was ever a book describing a mechanical "analog computer" - and what they might even look like. There have been mechanical analogue computers and I have at least one book describing them on my shelves. Typically they used disc integrators with an igenious arrangement of strings and drums as a torque amplifier. These were then coupled by gearing which had to be set up for each problem (simple gear trains correspond to fixed gain amplifiers, differential gear trains to differential amplfiiers, etc). I doubt you could make one from cardboard, but there was at least one UK University that made a simple one from Meccano (similar to Erector Sets across the Pond?). It was on show, not operating, in the London Science Museum at one time, but I think it's in storage now, -tony Fluid computing, tech of the future. Or it was in 1968...
[cctalk] Re: what to do with our "treasures"
On 2024-07-02 6:42 p.m., Ali via cctalk wrote: Totally opposite. GSP rates from the US to UK were crazy cheap. I sold a bunch of items. Compared to USPS rates they were 1/3 often. Again I am talking about getting stuff from the UK to the US. Generally speaking it seems like shipping from the US to anywhere (except maybe China) is cheaper than the opposite direction. I.e. for me to ship to Canada, Australia, Europe generally is much cheaper than if I was to buy the same item and have them ship it to me from those destinations. YMMV. -Ali But are we dealing in rack mount equipment here? This mini looks rather large to ship. https://retrocomputingforum.com/t/20-bit-mini-ge-225-spotted-in-canberra-vcf/4234/2 Ben.
[cctalk] Re: what to do with our "treasures"
On 2024-07-02 1:05 p.m., Fred Cisin via cctalk wrote: On Tue, 2 Jul 2024, Adrian Godwin via cctalk wrote: Chinese to UK shipments are still relatively cheap but have also risen somewhat with more sellers charging for postage. eBay Chinese shipping seems impossibly low. Keep it that way, I need more IC's for a 16 bit computer. Does the Chinese guvmint sunsidize shipping exports? Does that influence the balance of trade? (and demise of USA industry?) Now we talk about it? HOW many clone APPLE II's do we need to return. Why not the "hunger marketing" of APPLE?
[cctalk] Re: what to do with our "treasures"
On 2024-07-01 6:31 p.m., Mike Stein via cctalk wrote: I've had the same experience with folks in Australia & NZ, accumulating stuff in the US until there's enough to ship it down under. I suspect today still shipping is better than it was in the 70's. It is just nobody wants to box and crate the stuff,and wait a few weeks on a ship any more. Ben. PS I suspect some people have so much stuff here, they could ship, to Australia, it could flip to up over.
[cctalk] Re: what to do with our "treasures"
On 2024-07-01 6:04 p.m., Mike Stein via cctalk wrote: Hey, I sent you a motherboard from Toronto all the way to the South Pole, remember? Well, OK, via San Francisco, but It wasn't too bad then. Hey there must be lots of vintage stuff at the south pole nobody ships stuff back. :)
[cctalk] Re: what to do with our "treasures"
On 2024-07-01 3:06 p.m., Ethan Dicks via cctalk wrote: On Mon, Jul 1, 2024 at 7:58 AM Liam Proven via cctalk wrote: ... vendors mostly refuse to ship internationally and buyers won't look at stuff that's abroad. If you aren't used to customs declaration forms, it can be a pain. Back in the 80s, I bought an Amiga accessory from a 2-man shop in Canada and they hadn't done a cross-border shipment before and because they didn't get it right, UPS held my package at the border and the Customs Broker wanted $80 USD to fill out a 1/2 page form ($220 in 2024 dollars). I declined their "help" and the package went back to the seller to fix. I rarely buy from overseas sellers because $30-$40/kg postage is too dear. -ethan Things have not improved for shipping to CANADA from the USA. Now it is $80 for $2.0 chip from the USA. I expect to pay for shipping from China for bulk things like bypass caps, the same as the cost of the part. It was $5.00 for shipping for The Baker's Scoop Seasoned Frying Flour 3.5 Lb (Pack of 2) off Amazon.
[cctalk] Re: Revocable Living Trust for Computer Collectors
On 2024-06-27 9:22 a.m., Jim Brain via cctalk wrote: The idea of leaving these items behind and thinking our loved ones will see any value from selling is ludicrous, though, and I question the sanity of those who seriously believe this. While I am sure there are exceptions to the rule, I do not believe there are many. I still say, if you think it is worth something, make sure you sell it yourself while you are still alive. Jim How many computers here, have been pulled out of the dumpster I wonder? Politics and management can be real ASSES on the value of something like computers. I grumble about the loss of knowledge in libraries as older computer books get trashed.A lot computers must get tossed also do to lack of software. Ben. Get a C64 now with a free dumpster.
[cctalk] Re: Intel 8086 - 46 yrs. ago
On 2024-06-13 4:30 p.m., Dave Dunfield via cctalk wrote: I think the 86 came at a good time/place because the 8080 series had become quite popular in microcomputers and designers were feeling the limits of a 8-bit architecture - the 86 provided a fairly powerful (for the time) and easy upgrade which was enough like the 8080 that most developers didn't have a tough time "figuring it out". (and it didn't hurt that minicomputer pricing wasn't involved) The Z8000 may be better. The 8088 was to be a better 8 bit cpu. Dave My own entry into the "microprocessor" design fray was something I called the: C-FLEA A very tiny/simple 16 bit CPU that was very optimal as a target for my C compiler. Never did see it to silicon, but did quite a few "virtual machines" - this let me efficiently put C code into little cpus that were not reasonable candidates for higher level languages. Where? I just finished a 20 bit cpu, that seems to have all the features a 16 bit cpu's had, but not all in one machine. Moving from word to byte/word addressing add one opcode bit. Index registers 7? as general purpose reg. Add 3 opcode bits. Removing skips, add one opcode bit. Hmm 21 bits already.. Looking for a C-compiler that is easy to re-target, and a OS to go with it. Ben.
[cctalk] Re: Intel 8086 - 46 yrs. ago
On 2024-06-13 12:06 p.m., Paul Koning via cctalk wrote: On Jun 13, 2024, at 2:00 PM, Chuck Guzis via cctalk wrote: On 6/13/24 10:32, Paul Koning via cctalk wrote: Huh? There is no direct connection between word length, register count, and pipeline length. Indeed. There are architectures with NO user-addressable registers. Some have memory-mapped registers, where a "register number" is merely shorthand for a memory address (i.e. implicit multiplier and base) --Chuck There are of course also machines that appear to have registers (in the sense that the instruction set refers to them) but the implementation is a chunk of memory. The PDP-6 is one (and early PDP-10s without the "fast registers" option). The Philips PR-8000 may be one as well; the ISA has 8 registers, times 8 because it has a separate set per interrupt priority level, but there is a variant of the store instruction that stores to any of these as if it were memory. I'm not actually sure if it was implemented that way; 64 registers 24 bits wide would be a substantial cost and bulk in a mid-1960s machine. paul Index registers like on, the IBM 1130 worked that way. The PDP-5 I think had the fewest internal registers. (Never heard of Nuclear plan fail with PDP-5). B.
[cctalk] Re: Intel 8086 - 46 yrs. ago
On 2024-06-13 11:32 a.m., Paul Koning via cctalk wrote: e up an entire chassis, 750-ish logic modules. You never see a gate level delays on a spec sheet. Our pipeline is X delays + N delays for a latch. Gate level delays are not interesting for the machine user to know. What is interesting is the detailed properties of the pipelines, including whether they can accept a new operation every cycle or just every N cycles (say, a multiplier that accepts operands every 2 cycles); how many cycles is the delay from input to output; and whether there are "bypass" data paths to reduce the delays from input or output conflicts. Often these details are hard to pry out of the manufacturer; often they are not documented in the standard data sheets or processor user manuals. But they are critical if you want to do work such as pipeline models to drive compiler optimizers. But I want to know, how to compare machines if you can't compare the logic. paul I never did see much in optimization at the RTL level. You have to wait for data, regardless of fancy tricks.
[cctalk] Re: Intel 8086 - 46 yrs. ago
On 2024-06-13 9:40 a.m., Jon Elson via cctalk wrote: AACK! Sorry, that was supposed to be F-16! The divide bug strikes again. Jon What would one use today instead of the 586? Ben.
[cctalk] Re: teletype roll as an RF termination load
On 2024-06-12 8:17 p.m., Dennis Boone via cctalk wrote: > I wouldn't think it would work much better than a light bulb, though. Load it up with a wide range tuner, and you could probably make contacts across three states, though, just like the light bulb. :) De Wow the worlds cheapest RTTY setup, or is it fewest parts. Does any one do RTTY or slow scan TV now days? Ben.
[cctalk] Re: Intel 8086 - 46 yrs. ago
On 2024-06-10 10:05 a.m., Joshua Rice via cctalk wrote: On 10/06/2024 00:28, ben via cctalk wrote: The CPU Price it keeps going UP ... :( 8008 $25 1975 8080 $75 MITS kit 1975 8088 $125 386 $130 (286 $20) Hardly, you can pick up a new CPU today for less than $50. It's not going to be particularly fast, but it'll run circles round most decade old CPUs. I thought a PI was $10. I think the biggest change (other than speed, word length etc), is number of SKUs. For desktop systems, there are dozens of different SKUs per microarchitecture, each with varying cache size, core count, clockspeed, and present/absent integrated graphics. In the server space, the varying SKUs are amplified, with number of PCIe lanes, socket support etc almost multiplying the number of SKUs by an order of magnitude. Josh Rice I got a headache from reading that. Really a minor point, architecture has not gotten better since the RISC/CISC debate, just faster clock speeds, newer graphic processors and the like, in my view. Ben. Gates's law "The speed of software halves every 18 months"
[cctalk] Re: Intel 8086 - 46 yrs. ago
On 2024-06-10 10:18 a.m., Joshua Rice via cctalk wrote: On 10/06/2024 05:54, dwight via cctalk wrote: No one is mentioning multiple processors on a single die and cache that is bigger than most systems of that times complete RAM. Clock speed was dealt with clever register reassignment, pipelining and prediction. Dwight Pipelining has always been a double edged sword. Splitting the instruction cycle into smaller, faster chunks that can run simultaneously is a great idea, but if the actual instruction execution speed gets longer, failed branch predictions and subsequent pipeline flushes can truly bog down the real-life IPS. This is ultimately what led the NetBurst architecture to be the dead-end it became. The other gotya with pipelining, is you have to have equal size chunks. A 16 word register file seems to be right size for a 16 bit alu. 64 words for words for 32 bit alu. 256 words for 64 bit alu, as a guess. You never see a gate level delays on a spec sheet. Our pipeline is X delays + N delays for a latch. How Fast Can Computers Add? Scientific American Vol. 219, No. 4 (October 1968), pp. 93-101 (9 pages) I do not think that will change vs MORE's law, LESS's law, BIG MONEY's law. DEC came across another issue with the PDP-11 vs the VAX. Although the pipelined architecture of the VAX was much faster than the PDP-11, the actual time for a single instruction cycle was much increased, which led to customers requiring real-time operation to stick with the PDP-11, as Forget that, noise. PDP 11's dirt cheap compared to VAX. > it was much quicker in those operations. This, along with it's large > software back-catalog and established platform led to the PDP-11 > outliving it's successor. Josh Rice Now that makes more sense.
[cctalk] Re: Intel 8086 - 46 yrs. ago
On 2024-06-09 11:01 a.m., Chuck Guzis via cctalk wrote: On 6/9/24 08:40, Murray McCullough via cctalk wrote: Intel introduced to the world the x86 processor: the CISC technology still with us. So what has changed other than speed and upward development? The Internet? Really, it's always been my view that computational technical progress has long been driven by communication. Without communication, the microprocessor would largely be limited to commercial (e.g. CAD, finance, accounting) and a few niche applications. Many of those segments would be just fine with older technology. To put it in another context, what use would most people find with a PC that was limited to 300 bps modem communication? --Chuck More reliable. Can you trust a CLOUD? How soon will your data be corrupted, or behind a paywall?
[cctalk] Re: Intel 8086 - 46 yrs. ago
On 2024-06-09 10:59 a.m., Milo Velimirović via cctalk wrote: Word length. :) On Jun 9, 2024, at 10:40 AM, Murray McCullough via cctalk wrote: Intel introduced to the world the x86 processor: the CISC technology still with us. So what has changed other than speed and upward development? Happy computing, Murray 🙂 The CPU Price it keeps going UP ... :( 8008 $25 1975 8080 $75 MITS kit 1975 8088 $125 386 $130 (286 $20)
[cctalk] Re: terminology [was: First Personal Computer]
On 2024-05-28 5:45 p.m., Chuck Guzis via cctalk wrote: On 5/28/24 16:29, ben via cctalk wrote: On 2024-05-28 1:23 p.m., John via cctalk wrote: So what, then, consitutes a Real Operating System, and why? I am grumpy about OS's like MSDOS, in that programs kept by passing DOS to handle screen, and serial IO. I also favor OS's that don't require one to build a file control block. Do you mean like MSDOS (later functions use file handles, not FCBs)? Been like that since about DOS 2.0... --Chuck True, but serial IO was never fixed to my knowledge to use interrupts.
[cctalk] Re: terminology [was: First Personal Computer]
On 2024-05-28 1:23 p.m., John via cctalk wrote: So what, then, consitutes a Real Operating System, and why? I am grumpy about OS's like MSDOS, in that programs kept by passing DOS to handle screen, and serial IO. I also favor OS's that don't require one to build a file control block.
[cctalk] Re: First Personal Computer
On 2024-05-28 10:58 a.m., Tony Duell wrote: On Tue, May 28, 2024 at 5:56 PM ben via cctalk wrote: --First Appartment I lived in had gas refrigerator/stove AND still had some fixtures for gas lighting. washer/dryer/furnace/hot water were all shared in basement, real screw in fuses (not safety) so MAYBE had 220 if you used extension cords to two rooms, probably 10 amps. --townhouse my parents moved to had 220 at the circuit box, but intended for gas appliances and you either bought central AC before construction completed, or tough luck, so no 220 outlets. --my first two personal apartments again no 220, probably 15 A Still wanting a GAS Computer? :) I once repaired a gas radio (dating from the 1930s). No I am not joking. -tony Just what is a gas radio?
[cctalk] Re: Pragmatically [was: Experience using an Altair 8800 ("Personal computer" from 70s)]
Same concept as, if one guy living in a formerly industrial loft has water cooling, and 300 amp 3 phase power available, that does NOT make any computer requiring that "personal". For that I'd say must be able to plug into 50% of all homes, but realize more quibbling might apply there, such as 90% of all "middle class" homes. For me to have a computer, means taking it 3 flights of stairs. Thus most vintage computers, I don't even think about them.
[cctalk] Re: First Personal Computer
On 2024-05-28 8:43 a.m., CAREY SCHUG via cctalk wrote: so if ONE person maybe living in a loft formerly industrial space has water cooling, and 200 amp 3 phase in their house, that automatically makes EVERY computer using that power personal computer eligible? --First Appartment I lived in had gas refrigerator/stove AND still had some fixtures for gas lighting. washer/dryer/furnace/hot water were all shared in basement, real screw in fuses (not safety) so MAYBE had 220 if you used extension cords to two rooms, probably 10 amps. --townhouse my parents moved to had 220 at the circuit box, but intended for gas appliances and you either bought central AC before construction completed, or tough luck, so no 220 outlets. --my first two personal apartments again no 220, probably 15 A Still wanting a GAS Computer? :)
[cctalk] Re: First Personal Computer
On 2024-05-27 6:23 a.m., Christian Corti via cctalk wrote: On Sat, 25 May 2024, Chuck Guzis wrote: Offhand, if I were King of the World, I'd immediately eliminate from competition those computers that cannot be run from a US 120 volt 15 amp wall receptacle. The rationale being that anything that requires special power wiring cannot be "personal" I I were King of the World, I'd immediately ban everything non-standard like 110/120V, 208V two-phase and 60Hz ish as well as everything non-metric/SI based ;-) I would ban the eruo and the metric system. Bring back British rule. Long live the KING. So, for example, the PB-250 qualifies; the IBM 1130 does not. The The IBM 1130 *does* run on a simple wall power outlet if you don't have the 1133 I/O multiplexer. Christian I/O motors can be adapted I suspect for phase and power. Remember not needing a raised floor and AC was big selling point of the IBM 1130 in the 1960's. Four-Phase Systems, had a impressive system in the 1970's. One 24 bit box with up to 32 terminals in 1974. The IBM 1130 was retired around then,and it was good time for 24 bit computers.
[cctalk] Re: terminology [was: First Personal Computer]
On 2024-05-26 2:01 p.m., Chuck Guzis via cctalk wrote: On 5/26/24 11:11, ben via cctalk wrote: On 2024-05-26 10:56 a.m., Fred Cisin via cctalk wrote: I did use a CP/M machine once, but the 8" drive was a bit sticky. You rap the drive to get it unstuck, but if you rap it too hard the machine would reset. Fred, just forget it. We belong to a bygone era and there's no sense in trying to explain things to the younger folk. However, perhaps someone can tell me why an HP-41 or TI SR-52 isn't a "personal computer"... You can't play space invaders on it. --Chuck Since IBM defined the PC, let's leave it that for what a PC is. The technology was only ready at the 1981 ish time frame, for the personal market. I favor the IBM 1130 as the first personal computer. Most of my nit picking is with having low income, quality software and hardware is hard to find. My personal gripe, is that rather than building a cleaner text OS,every body jumped on having TV video game operating systems, like windows. The mac was better, but I don't think it did a 8x10 full page of text, like the original experimental operating systems.
[cctalk] Re: terminology [was: First Personal Computer]
On 2024-05-26 10:56 a.m., Fred Cisin via cctalk wrote: On Sun, 26 May 2024, ben via cctalk wrote: I think the most important thing for a Personal Computer, is the average Joe, can afford and use it. The second thing is to have ample memory and IO to run useful programs. The basic Apple I,II does not count as many others as it had BASIC in ROM and tape IO. The third thing is a real OS. Nobody has one, as a personal computer. CP/M and MSDOS does not handle IRQ's. Unix for the PDP-11 is real operating system but not personal as it requires a admin,and a swapping media. So, basically, the first "Personal Computer" does not yet exist, and all of those being discussed are merely predecessors for it. I can definitely agree with that, although not necessarily with your specific list of requirements. Although there need to be some that Joe Average can afford, they don't all need to be, as a requirement; Tony Cole can build a gold plated one, and billg can spec optional features that the rest of us can't afford - if I were designing billg's house, I'd build some "personal" computing capability in the walls, or filling the main rooms, and bedroom could be a cot in the walls. I want more books and shelves to with them. That a side, how many people here still use the 16Kb (favorite machine) with tape IO? I did use a CP/M machine once, but the 8" drive was a bit sticky. You rap the drive to get it unstuck, but if you rap it too hard the machine would reset. "Ample memory"??!? perhaps that should be TerrorBytes. I/O??!? Does that need to be built in, in the minimum purchase configuration, or merely provision for it externally? For non graphics, I say 64kb for a 8 bit machine with basic in rom. CP/M 32K. "Real OS"? While I don't agree with your specific examples of inadequacies, I will readily concede that nothing so far is ready for the title. CP/M was the cats meyow in the 1970's,but there was other systems out like flex for the 6800, or later OS/9 for the 6809. Don't they get a chance too for real OS. -- Grumpy Ol' Fred ci...@xenosoft.com
[cctalk] Re: First Personal Computer
On 2024-05-25 3:57 p.m., Chuck Guzis via cctalk wrote: On 5/25/24 13:41, Fred Cisin via cctalk wrote: On Sat, 25 May 2024, Chuck Guzis via cctalk wrote: . . . or 100V or 220V in locations where those are the standard for household residential wiring. Woulld not want to automatically exclude UK machines, such as the Sinclair doorstop wedge. Okay, I'll refine it for the international crowd. Anything that requires over 1800 VA to run isn't a "personal computer" That's about 8 amps for the 220 volt world. --Chuck That means all the NEW gaming PC's have been deleted from this discussion, Good job. :)
[cctalk] Re: terminology [was: First Personal Computer]
On 2024-05-25 5:42 p.m., Mike Katz via cctalk wrote: I'm sorry but I beg to differ with you here. The DEC PDP line of single user interactive computers (as opposed to batch processing only systems) started in the late 1950's and early 1960's and spawned many generations as well as copies and other companies (Data General being the most well known of these).Yes multi user time sharing operating systems we added later on but initially they were single user interactive, (DEC 10 & 20 excepted).Does a computer lose its "Personal" identification if it can handle multiple users as an option. There were multiple user time sharing Operating Systems for many early personal computers (Unix, Xenix, MP/M, Uniflex, OS/9, etc.). Even the aforementioned PDP computers ran multi-user time sharing systems. Does that, then, invalidate them for consideration as a personal computer? Does that make any Linux machine not a personal computer, by definition, because it can handle more than one user or task? As I have said earlier in this thead and its fore bearers, the term Personal Computer is so non-specific that we can argue from here to Alpha Centauri and back without coming up with an agreed upon definition. So, until a concrete definition can be made, the discussion of the answer is completely moot. I stick by my original challenge, find a calculating device that predates the Antikythera Mechanism (36 BCE). Simple measuring devices like the sun dial and sextant don't count as they don't calculate, they measure. I think the most important thing for a Personal Computer, is the average Joe, can afford and use it. The second thing is to have ample memory and IO to run useful programs. The basic Apple I,II does not count as many others as it had BASIC in ROM and tape IO. The third thing is a real OS. Nobody has one, as a personal computer. CP/M and MSDOS does not handle IRQ's. Unix for the PDP-11 is real operating system but not personal as it requires a admin,and a swapping media.
[cctalk] Re: interlace [was: NTSC TV demodulator ]
On 2024-05-20 12:16 p.m., Will Cooke via cctalk wrote: On 05/20/2024 1:02 PM CDT Wayne S via cctalk wrote: In the vt100, setup menu “B” had an interlace on or off setting. I just looked it up. That is almost certainly setting what type of signal is generated. Like a TV of the same era, the monitor (display) portion doesn't care; it just displays what it is sent. That is very different from a monitor setting that sets either interlaced or non-interlaced. Some reasons why you might prefer one over the other on the same screen: non-interlaced would have a horizontal gap between displayed lines whereas interlaced would fill them in. However, interlaced is more prone to flickering, which can be very tiring to the eyes and cause headaches. Will And you have Color VS B&W.
[cctalk] Re: Thirties techies and computing history
Don't get your mind get old. It’s a choice. My mind is fine, it the eyes that are going. Screens are getting bigger and text is getting smaller. I must be dreaming that.
[cctalk] Re: Thirties techies and computing history
On 2024-05-19 9:14 a.m., Tarek Hoteit via cctalk wrote: A friend of a friend had a birthday gathering. Everyone there was in their thirties, except for myself, my wife, and our friend. Anyway, I met a Google engineer, a Microsoft data scientist, an Amazon AWS recruiter (I think she was a recruiter), and a few others in tech who are friends with the party host. I had several conversations about computer origins, the early days of computing, its importance in what we have today, and so on. What I found disappointing and saddening at the same time is their utmost ignorance about computing history or even early computers. Except for their recall of the 3.5 floppy or early 2000’s Windows, there was absolutely nothing else that they were familiar with. That made me wonder if this is a sign that our living version of classical personal computing, in which many of us here in this group witnessed the invention of personal computing in the 70s, will stop with our generation. I assume that the most engaging folks in this newsgroup are in their fifties and beyond. (No offense to anyone. I am turning fifty myself) I sense that no other generation following this user group's generation will ever talk about Altairs, CP/M s, PDPs, S100 buses, Pascal, or anything deemed exciting in computing. Is there hope, or is this the end of the line for the most exciting era of personal computers? Thoughts? Regards, Tarek Hoteit Well with the internet I have been finding a lot more about behind the history of the 1970's. The West Coast made the chips, and the East coast made the computers, while here in Canada,We just got to watch computers on TV with the blinking lights back then and the few chip sold by Radio Shack. Back then you could get to build a computer of some kind, on the kitchen table, as the knowledge was available, and parts Thu the hole. People are going retro simply because modern computers are too complex with documentation known to a few. The Z80 may be long gone, but I am sure lots of 8080's are sill for sale on ebay. I wanted to build a computer in my teens, and now I have time and the money. Looking back in time I see how bad the tech was back the for the average Joe. BASIC to rot your brain. 4K ram so you never learned how to comment stuff. Word lengths 4,8,16 so you spent all your time shoe horning a stuff to fit. Parts costing a arm and a leg, and three weeks for delivery. (Today parts from China 95 cents, 2 months delivery and arm and leg for shipping). My latest design on paper, requires 74LSXX,74H74,CY7C122 (25ns 256x4 ram),13 mhz osc, and lots of cmos 22V10's.A 18 bit serial cpu, with a memory cycle time of 2.25 uS. I am still working on my personal computer. Who knows,It might even work, but first the EMULATOR and cross assembler. Ben.
[cctalk] Re: DOS p-System Pascal: (Was: Saga of CP/M)
On 2024-05-10 1:01 p.m., Chuck Guzis via cctalk wrote: There have been some minor skirmishes in the MCU world over what language should be used when programming. EASY! OCTAL! If it worked on the 8 it is good enough for me. C/C++ is very much top dog, probably because the development suites are written for that. There's a small group that advocates Python; and some say that Ada is best. But they represent a very small segment. --Chuck I think it is more the case UNIX was around, and written in assembler. The egg. Then we got B, a Archaeopteryx and flock of chickens that all start with C. C generates real code output and not some virtual machine, another important factor as well as having bit fields and structures. The late 70's , early 80's where the golden years of computing. C,Pascal and PL/M are the only big names for 8 bit cpu's, and what came later.
[cctalk] Re: DOS p-System Pascal: (Was: Saga of CP/M)
On 2024-05-09 1:23 p.m., John via cctalk wrote: Pascal never really made it on the microcomputer platform did it? I can be convinced otherwise but it seems like microcomputing Pascal was more of a staging environment for then upload into a production mainframe/mini Pascal was the language of choice over at Apple in the original MacOS days, and as Mike has noted Turbo Pascal was popular enough on the PC; it was more, I think, that the UCSD-style language-environment-as-OS paradigm never caught on in the microcomputer world. Early consumer micros of course had ROM BASIC, but once you got past that to a reasonably full-featured operating system, there was no compelling reason for it to be tightly coupled to one particular language/compiler when it could just as easily treat compilers as Yet Another Program and support arbitrarily many. And every one maxed out with small model for the IBM PC, and 48K for CP/M. Did any one make a REAL TIME OS the 386?
[cctalk] Re: FWIW CD & DVD demagnitizitation [was: Double Density 3.5" Floppy Disks]
On 2024-05-07 9:53 p.m., Tony Duell via cctalk wrote: Anyway, some of their engineers were setting up for an exhibition/demonstration when they realised they'd forgotten to bring any speaker cable. No problem, one of them goes to the local 'DIY Shed' (large hardware store) and buys some normal mains cable[1]. They use this and not surprisingly it sounds great. [1] Apparently there's a slogan on the wall of the QUAD workshop 'Ohm's Law rules here. Oxygen-free cable is not required' Next day, said chain of 'DIY sheds' gets a run on that mains cable. Audiophools were buying this magic speaker cable -tony Nice story. QUAD is a bit outdated. Australa is the place for electrostatic speakers, http://www.eraudio.com.au/
[cctalk] Re: FWIW CD & DVD demagnitizitation [was: Double Density 3.5" Floppy Disks]
On 2024-05-07 5:51 p.m., Chuck Guzis via cctalk wrote: On 5/7/24 15:21, Fred Cisin via cctalk wrote: How difficult is it to measure and compare "With/Without" signals? If you peruse the old Bob Pease articles on "Electronic Design" magazine, I believe more than once, he alluded to a proposed "blind test"--two boxes; one filled with the latest audiophilatic super speaker cable and the other with standard lamp cord with splices. I don't believe that anyone took him up on the proposed challenge. --Chuck Orichalcum has been rediscovered. I say use that!
[cctalk] Re: APL (Was: BASIC
On 2024-05-02 4:55 a.m., Liam Proven via cctalk wrote: On Thu, 2 May 2024 at 00:51, Fred Cisin via cctalk wrote: What would our world be like if the first home computers were to have had APL, instead of BASIC? To be perfectly honest I think the home computer boom wouldn't have happened, and it would have crashed and burned in the 1970s, with the result that microcomputers remained firmly under corporate control. I have been watching the APL world with interest since I discovered it at university, and I still don't understand a word of it. I've been watching Lisp for just 15 years or so and I find it unreadable too. I think there are widely different levels of mental flexibility among smart humans and one person's "this just requires a small effort but you get so much in return!" is someone else's eternally impossible, unclimbable mountain. After some 40 years in computers now, I still like BASIC best, with Fortran and Pascal very distant runners-up and everything else from C to Python is basically somewhere between Minoan Linear A and Linear B to me. I think I lack the mental flexibility, and I think I'm better than most of hoi polloi. If the early machines had used something cryptic like APL or Forth I reckon we'd never have had a generation of child programmers. I have very poor memory, IF,REM,LET ect I can remember. Line noise like TELCO err APL I can not make sense at all. USA(IBM) pushed APL , Europe wanted ALGOL. What users got was STUPID ASCII and the useless accent marks. Without real IO lots of languages died, and we got C and Pascal but only for the US. That just left BASIC the standard as it just needed A-Z0-9[]+-=><;" BASIC would be still around in ALT UNIVERSE running off the cloud.
[cctalk] Re: What to take to a vintage computer show
On 2024-05-01 11:26 p.m., Ali via cctalk wrote: Don't forget to bring a towel. Sellam The fact that we all probably got that reference is the amazing part. -Ali What no white mouse trap!
[cctalk] Re: PCs in home vs businesses (70s/80s)
On 2024-04-27 2:29 p.m., Paul Koning via cctalk wrote:
On Apr 27, 2024, at 1:15 PM, Tarek Hoteit via cctalk
wrote:
I came across this paragraph from the July 1981 Popular Science magazine
edition in the article titled “Compute power - pro models at almost home-unit
prices.”
“ ‘Personal-computer buffs may buy a machine, bring it home, and then spend the
rest of their time looking for things it can do’, said …. ‘In business, it’s
the other way around. Here you know the job, you have to find a machine that
will do it. More precisely, you have to find software that will do the job.
Finding a computer to use the software you’ve selected becomes secondary.”.
Do you guys* think that software drove hardware sales rather than the other way
around for businesses in the early days? I recall that computer hardware
salespeople would be knocking on businesses office doors rather than software
salesmen. Just seeking your opinion now that we are far ahead from 1981.
Not PCs, but the first systems I worked on for DEC were turnkey PDP-11 based
systems for newspaper production. Clearly the customer wanted to publish
newspapers, and the hardware involved wasn't what drove the decision. A lot of
our competitors were specialized companies concentrating on that particular
business, not computer makers. For example, arguably the top company at the
time (Atex, if I remember right) also used PDP-11s. That was around 1978.
Also about that time, I worked with some people running a computer store in the LA area
("Rainbow Computing") on a proposal for a business application. That was a
work scheduling and routing system for hospitals, and there too the point of it was the
application needed to solve the business problem, not the hardware on which it would run.
paul
Did any one need REAL BCD math like the Big Boys had?
[cctalk] Re: OFF TOPIC: Doctor Who
https://www.youtube.com/watch?v=iJeu3LCo-6A Dr who ads for prime.
[cctalk] Re: Z80 vs other microprocessors of the time.
On 2024-04-24 2:55 p.m., Gordon Henderson via cctalk wrote: On Wed, 24 Apr 2024, David Brownlee via cctalk wrote: If we're talking about machines with a Z80 and 6502, it would be remiss not to link back to the machine mentioned in the original message - the BBC micro, with its onboard 6502 and "Tube" interface which could take a second processor option, including - Z80 - 65C02 / 65C102 - NS 16032 (ahem 32016) - 8088 (Torch) / 80186, 80286 (last developed but never released) - ARM1 (Original ARM development board. Rare as hens teeth :) / ARM7 (someone having a laugh in later years) Typically the second processor would run as primary, using the original 6502 to handle input, display and I/O (and on 32016 you *really* wanted someone else to deal with anything time critical like interrupts :) "later years" is .. Today where we connect a Raspbery Pi to the BBC Micros Tube interface and emulate all those CPUs and several more like the PDP/11. One of the 6502 emulations runs at the equivalent of a 275Mhz CPU... So if you want a Z80 then emulate it - it runs CP/M just as well as any other CP/M system. The original ARM2 is there too. The current list: n Processor - *FX 151,230,n 0 * 65C02 (fast) 1 65C02 (3MHz, for games compatbility) 2 65C102 (fast) 3 65C102 (4MHz, for games compatbility) 4 Z80 (1.21) 5 Z80 (2.00) 6 Z80 (2.2c) 7 Z80 (2.30) 8 80286 9 MC6809 11 PDP-11 12 ARM2 13 32016 14 Disable 15 ARM Native 16 LIB65C02 64K 17 LIB65C02 256K Turbo 18 65C816 (Dossy) 19 65C816 (ReCo) 20 OPC5LS 21 OPC6 22 OPC7 24 65C02 (JIT) 28 Ferranti F100-L Cheers, -Gordon This would be great, but I live on the other side of the pond and BBC anything is hard to find, let alone Micro's. Where is my "Dr. Who". Ben.
[cctalk] Re: Z80 vs other microprocessors of the time.
On 2024-04-23 8:40 p.m., Chuck Guzis via cctalk wrote: On 4/23/24 17:18, Bill Gunshannon via cctalk wrote: On 4/23/2024 8:06 PM, Fred Cisin via cctalk wrote: Did the Dimension 68000 (a multi-processor machine) have Z80 and 6502? Couldn't Bill Godbout's CPU-68K board co-exist with other CPU boards? --Chuck I remember Bill Godbout's PACE ads. Now I got the $$$ and time I can't find any chips.
[cctalk] Re: Z80 vs other microprocessors of the time.
On 2024-04-22 1:02 p.m., Chuck Guzis via cctalk wrote: I'd like to see a Z80 implemented with UV-201 vacuum tubes... :) --Chuck Real computers use glow tubes like the NE-2 or the NE-77.:)
[cctalk] Re: Z80 vs other microprocessors of the time.
>One other factor is that RISC machines rely on simple operations >carefully arranged by optimizing compilers (or, in some cases, >skillful programmers). A multi-step operation can be encoded in a >sequence of RISC operations run through an optimizing scheduler more >effectively than the equivalent sequence of steps inside the >micro-engine of a CISC processor. Lets call them LOAD/STORE architectures. Classic cpu designs like the PDP-1, might be better called RISC. Back then you matched the cpu word length to data you were using. 40 bits made a lot of sense for real computing, even if you had no RAM memory at the time, just drum. IBM set the standard for 8 bit bytes, 16, 32 bit words and 64 bit floating point. Things are complex because you need to pack things to fit the standard size boxes. Every thing is trade off. Why? Because the IBM 7030 Stretch (64 bits) was a flop. Save memory, CISC. Use memory, RISC. Simple memory, Microprocessors. Processor development, is always built around what memory you have around at the time, is my argument. How many Z80's can you think of USE core memory? I think only 1 8080A ever used core memory, from BYTE magazine. Improvements in memory often where improvements in logic as well for CPU design. If CPU's were designed for high level languages, why are there no stack based architectures around like for Pascal's P-code? (1970's yes, but not today) The Z80 may be gone, but the 8080 still can be emulated by bitslices. Did anyone ever use them? Ben.
[cctalk] Re: Last Buy notification for Z80 (Z84C00 Product line)
On 2024-04-21 5:26 p.m., Chuck Guzis via cctalk wrote: On 4/21/24 12:11, ben via cctalk wrote: I keep finding I still need 74XX just for having 10 TTL loads, and 74LSXX just does not have the power. Ever try BiCMOS chips? IIRC, the 74ABTxxx will drive loads of up to 60 ma, far in excess of old 74xx parts. --Chuck Thru the hole and 5 volt and cheap and easy to find ( at one time ) and low edge rates , are important for me as I have kitchen table kind of projects. Before you say use XXX , I don't have the skills or the tools to layout and debug high tech boards or parts. I am very unlucky with FPGA stuff. My current bit slice computer design has some sort of dynamic problem, as only some instructions will run or read correctly. Halt and STOP don't work. Front panel works mostly. I need to rethink a whole new design,as something I can build and test and find parts for. The goal is a 20 bit word length computer, with 10 bit bytes,bit slices, Compact flash , UART's and blinking light front panel. I may run in emulation, until I can get hardware built and debugged but I have not found a host computer I like. So if any one wishes to take on this project, feel free using modern parts. Ben. * april 21 2024 sdc 1 Small Data Processor 1 .815 uS CYCLE TIME - BYTE BASED COMPUTER - INDEX REG'S - REGISTER OPS - CARRY BIT - AUTO/INDEX - LOGIC OPERATIONS - HEX FRONT PANEL MM 00 0 0 10 2 1 01 WRDwrd 11 SEXsx 54321 ++++++ |:|:B321|+###| NORMAL ++++++ OP TC 0 ST SUB ADD 1 ADD ADD RAMU Z SUB 2 SUB SUB RAMU C SBR 3 CAD SBR RAMU S OR 4 LD ORAND 5 OR OR RAMD Z BIT 6 AND AND RAMD C XOR 7 XOR XOR RAMD S XNR F C0 0 0... CF F C0 0 1... UART i = index , 0 # CCC COND TRAP (0) <- PC PC <- 2 ADR LOAD N 0 H/ZST 1 A LD RAMU Z 2 B ADDRAMU C 3 C(carry)SUBRAMU S 4 G OR 5 X ANDRAMD Z 6 Y XORRAMD C 7 F/F JMPRAMD S REG C is CARRY IR PC CTL 0 0 TEST 0 1 DSP 1 0 HLT 1 1 DI/EI --- M1 = a/m1 M2 = b/m2 M3 = idx M3,M2,M1 ST OP 0 0 0CTL OP # 0 8 bits 0 0 1HLT SCC1 0 1 0ST R+ OP R+ 2 0 1 1JSV R+2 JCC R+2 3 1 0 0- REG4 1 0 1- SFT5 1 1 0ST @R+ OP @R+ 6 1 1 1ST XST X 7 --- '/' LINE COMMENT 'star' BLOCK COMMENT BEGIN/END ONLY #OOOOCTAL PROGRAM COUNTER __ | KROMA.PLD | CP x---|1 24|---x Vcc AD7 x---|2 23|---x WR AD6 x---|3 22|---x PRA0 AD5 x---|4 21|---x PRA1 AD4 x---|5 20|---x PRA2 AD3 x---|6 19|---x PRA3 AD2 x---|7 18|---x PRA4 AD1 x---|8 17|---x PRA5 AD0 x---|9 16|---x PRA6 AUX x---|10 15|---x PRA7 x---|11 14|---x M3 GND x---|12 13|---x CLR_ |__| [II8,sft,no,ld,ra,m2,m1,op,w,WR] __ | KROMB.PLD | CP x---|1 24|---x Vcc AD7 x---|2 23|---x BY AD6 x---|3 22|---x PRB0 AD5 x---|4 21|---x PRB1 AD4 x---|5 20|---x PRB2 AD3 x---|6 19|---x PRB3 AD2 x---|7 18|---x PRB4 AD1 x---|8 17|---x PRB5 AD0 x---|9 16|---x PRB6 aux x---|10 15|---x PRB7 x---|11 14|---x RD GND x---|12 13|---x CLR_ |__| [RD,ctl,rx,rd',in',ir,mar,rd,b,BY] OCTAL CPU FOR 20 BITS ( RUN,ST)(M3,M2,M1) (cnt 3,2,1) 7 65 4 3 2 1 0 * / TIMES ARE IN MICROSECONDS #100 / IDLE PANEL ALL 4 CLOCKS 3.26 AC SWMAR NO PCCTL
[cctalk] Re: Last Buy notification for Z80 (Z84C00 Product line)
On 2024-04-21 3:27 p.m., Jerry Weiss wrote: While intention might have been to last XX years, I am becoming increasingly pessimistic about longevity of most electronic devices. A crystal radio with an open air capacitor seems like the only good bet. Between electrolytic capacitor aging challenges, discrete and integrated circuit hermetic failures, cost or other inherent technical flaws, I fear most electronics will become inert over time. Many of us have the skills to identify and replace bits to extend the lifetime of many items. I only hope the skills and suitable replacement parts are available as time goes on. But if you want upgrade your radio, try here: http://www.r-type.org/articles/art-028.htm Most electronic devices have a known life time, sadly most of this information is never on the data sheet.
[cctalk] Re: Last Buy notification for Z80 (Z84C00 Product line)
On 2024-04-21 8:45 a.m., Mike Katz wrote: As for the RP2040 being cheap crap, I beg to differ with you. It is a solid chip, produced in 10s of millions at least. And, I would bet, a better quality chip than your Z-80, if due only to improved IC manufacturing technologies. The pi looks like parts were picked for lowest cost,biggest profit, like most products today. RISC chips have been around for 40 years, and yet versions change like hotcakes every year. I just want a product that is more robust, than the bleeding edge of technology. I product must meet my needs,not what some sales man said I need. I keep finding I still need 74XX just for having 10 TTL loads, and 74LSXX just does not have the power. Just because it's old doesn't make it good. I worked on a 32KHz 4 Bit CPU (about 20 years ago) where the development hardware was very unstable and the tool chain not a whole lot better. Early Microsoft and Lattice C compilers for the PC were buggy as hell. If you want I can list a few bugs from each of them in another thread. The PC was buggy as hell. Other than the 68000 and the National 16032 I can't think what real cpu is with more than 64Kb. The 386 has problems. The IBM 360 or VAX never made it the home market. The ARM was UK product. One of the biggest features of the Z-80, the extra register set, was rarely used in open source software in order to maintain compatibility with the 8080. I thought the main problem was you could not keep track of what set you were using. Some of the early Z-80 CP/M tools did not work because they were derived from 8080 tools. After time the tools got better. That is the case with any piece of software. If it doesn't become obsolete and if maintained it will get better over time. Most places only up grades software, if somebody pays for it. You can never get the OK to upgrade of fix software, but when you do they want it yesterday. Ben. PS: Looking the reply email, I say 20 bits is the best.
[cctalk] Re: PDP8 @ 50
https://www.youtube.com/watch?v=YXTQvlkYJvI&t=4s
[cctalk] Re: Last Buy notification for Z80 (Z84C00 Product line)
On 2024-04-20 8:33 p.m., Mike Katz via cctalk wrote: For anything more sophisticated than your coffee pot the RP2040 from Raspberry Pie is a fantastic little chip, dual core 133 MHz Cortex M0+ with 8 PIO engines, 264K of RAM, ADC, UART, SPI, I2C all for under a dollar. I designed a fully functional RP2040 with 16 Mb flash for under $2.00. In large enough quantities that's encroaching on 8 bit PIC territory at over 1000 times the memory and CPU power. I am wishing for a Quality Product, cheap crap is not always better. USB comes to mind. 256Kb ram is only 32K 64 bit words. Cache memory never works. My $5 internet toaster, just exploded after 3 days. So what? Just buy the new model that works with windows 12. Download a buggy new tool chain. The Z80 tools worked. The PDP8 was built to last. 50+ years and going strong. NOT the crappy PI PDP-8 or PDP-10. I give it 2 years max. Now a PI style computer with compact FLASH x 2, NO USB and 2 MEG ram , real serial and printer ports that will work in a noisy industrial setting, would be quite usefull. I'd pay even $3 for it. :)
[cctalk] Re: Last Buy notification for Z80 (Z84C00 Product line)
On 2024-04-20 12:20 p.m., Jim Brain via cctalk wrote: On 4/20/2024 1:16 PM, Wayne S wrote: Who still uses the Z80 line for new projects? Wouldn’t it be easier and cheaper to just use an Arduino or Raspberry Pi? Given the list you're posting on... :-) Jim True, but the Z80 is 5 volt logic. Still important in my mind plus timing is easy to figure out if you just need 8 bit logic.
[cctalk] Re: Last Buy notification for Z80 (Z84C00 Product line)
On 2024-04-19 8:07 p.m., Fred Cisin via cctalk wrote: Gee! Have sales gone down? One more reason to use the 8080 subset when writing CP/M programs. There still are RADIO SHACK 8080A's still on ebay, with @RARE@ prices. NO thank you, z80's are the way to go. Aren't there already some licensed second sources? Now is a good time to stock up for any z80 projects or repair, while they are $10 or less on epay.
[cctalk] Re: Bomar 901b My wife found in my stuff. Is this as scarce at it seems?s,?
On 2024-04-16 10:34 a.m., Van Snyder via cctalk wrote: On Tue, 2024-04-16 at 12:38 +0100, Adrian Godwin via cctalk wrote: 901B is the first pocket calculator I remember - I don't know if there were earlier ones. The first one I remember is the HP Digital Slide Rule, about 1965. Six digits. $600. Keep quiet, now all old calculators will be $600 on ebay.
[cctalk] Other input devices.
Did any one ever use a keyboard to magtape as input device?
[cctalk] Re: Odd IBM mass storage systems
On 2024-04-12 7:23 p.m., Paul Koning via cctalk wrote: On Apr 12, 2024, at 5:54 PM, CAREY SCHUG via cctalk wrote: ... my favorite terminal 3190 that was neon gas, so monochrome, but could take 5 addresses, and flip between 62 lines of 160 characters (always there), to 4 terminals of 62x80 any two visible at a time, or 4 terminals of 31x160 characters, any 2 visible at a time, or 4 terminals of 31x80 all visible at once. when given a choice, my new boss was surprised that I chose that instead of the color 3279 with graphics that everybody else wanted. Great for running virtual systems... Sounds like the plasma panel displays that were invented for the PLATO system, by Don Bitzer and a few others, at the U of Illinois. Inherent memory: if you lit a pixel it would stay lit, to turn it off you'd feed it a pulse of the opposite polarity. So it was a great way to do 512x512 bitmap graphics with very modest complexity, no refresh memory needed. paul But too slow I suspect to run a game like spacewar.
[cctalk] Re: IBM 360
On 2024-04-09 8:53 p.m., Murray McCullough via cctalk wrote: I had not realized the IBM 360 was 60 yrs. old this month. I worked on such a computer in the late 60s in Toronto. What one could do with 8 Kbytes of ram was remarkable! Happy computing Murray 🙂 Real time sharing, not a 16K PDP 8?
[cctalk] Re: Borland Turbo C++ and Turbo Basic - Books and Manuals
On 2024-04-07 3:33 p.m., Just Kant via cctalk wrote: What about cans? They don't shatter. What? Too American? I mean I won't drink out of anything but glass. But dad used to drink those tall boy Rheingold and Schaeffer. He was so nasty in the mornings. Sent with Proton Mail secure email. On Sunday, April 7th, 2024 at 4:14 PM, Harald Arnesen via cctalk wrote: ben via cctalk [07/04/2024 20.05]: I don't think bottles would be ship able. Now a keg of beer might be. Or a least the old oak kegs you read in stories. No problem to ship beer bottles, just pack them in diapers. We do this all the time in the Norwegian homebrew competitions. Now, diapers are the only thing really cheap in Norway. -- Hilsen Harald. But kegs are more fun.
[cctalk] Re: Borland Turbo C++ and Turbo Basic - Books and Manuals
On 2024-04-07 5:57 a.m., Christian Groessler via cctalk wrote: On 4/6/24 5:37 PM, Mike Norris via cctalk wrote: Additional I would like £5 beer money for this one please! Writing Open VMS Alpha Device Drivers in C - Margie Sherlock/Leonard Szubowicz I'd take it. I can send you beer money, or could send you 2 or 3 bottles of local beer. I'm living near Munich, Germany. Sending beer will likely be quite more expensive than 5 pounds, but has a fun factor bonus :-) regards, chris I don't think bottles would be ship able. Now a keg of beer might be. Or a least the old oak kegs you read in stories. Ben.
[cctalk] Re: oscilloscopes
On 2024-04-06 9:40 a.m., Phil Budne via cctalk wrote: Paul Koning wrote: Yes, and some emulations have done this, such as Phil Budne's famous work in SIMH. Famous?? I'm famous???!!! To be fair, I started with Douglas W. Jones' PDP8 Emulator. Which reminds me of: If I have seen farther than others, it is because I was standing on the shoulders of giants. -- Isaac Newton In the sciences, we are now uniquely privileged to sit side by side with the giants on whose shoulders we stand. -- Gerald Holton If I have not seen as far as others, it is because giants were standing on my shoulders. -- Hal Abelson In computer science, we stand on each other's feet. -- Brian K. Reid It was certainly an awakening to the inherent parallelism of "analog" natural processes... I wrote and tuned the code twenty years ago, but haven't looked at whether better results might be possible by wasting the capabilities of current systems (SIMD libaries and/or multiple cores). I felt like I only was able to give a slim impression, and not an immersive experience. I've also wondered what could be done with 4K HDR displays: making points round(!) and simulating the "bloom" and intensity of repeatedly or highly intensified spots. phil I need to write a emulator for a new cpu design I have. The 1086 cpu, nice 20 bit cpu design from about 1968 using more modern parts. The problem is the modern parts are just too fast and I have timing issues. I can read/ write from memory using the front panel but not run code for some reason. Jumps seem to work but HALT does not. This requires a whole new bunch of PCB's with test points and other bug fixes, and I have few weeks waiting for more parts. I figure 90% of the code will be planning simple IO for this beast and 10% the emulator itself. I like real hardware that you can put a scope too. All I can say modern programming is a about using a GUI and very little about console IO. This is a bit change from using a PDP-8 with TTY, and 4K focal.
[cctalk] Re: typical IC kits on Amazon and elsewhere
On 2024-03-30 9:49 p.m., Tom Hunter via cctalk wrote: Sorry I mistyped. I meant Mouser and Digikey, not Amazon and Digikey. Well the searches suck on both. Digikey is bad for having 0 stock listings. Digikey is turning out to be more the Radio Shack for parts.
[cctalk] Re: typical IC kits on Amazon and elsewhere
On 2024-03-30 8:53 p.m., Glen Slick via cctalk wrote: You can also buy parts direct from TI, for example they currently show around around 3000 SN74LS04N parts in stock. https://www.ti.com/product/SN74LS04/part-details/SN74LS04N The prices for that part match the current Mouser prices of $0.674 each, or $0.519 each if you buy at least 4 tubes of 25 parts. I've bought some tubes of 74LS parts direct from TI in the last year. 185 In Stock 595-SN7404NE4 prices in canadian $'s QTY 1 $3.84 QTY 1000 $1.89
[cctalk] Re: typical IC kits on Amazon and elsewhere
On 2024-03-30 8:23 p.m., Jonathan Chapman via cctalk wrote: Been lurking for a while, but this topic hits true with some recent experiences. I would not hesitate to buy most common digital ICs on Amazon or ebay I mean we had to stop buying 7400 series from Jameco over counterfeits, so it's definitely a problem for jellybean parts too. We had so many reject 74F573 latches go out in XT-IDE kits we just scrapped the remaining Jameco-provided inventory. We also started having issues with 28C64B EEPROMs from them, obvious relabels that wouldn't program with the Atmel SDP algorithm -- that's actually why they started shipping pre-programmed in kits! Real shame, I've bought from Jameco since I was a kid, they'd actually sell to Just Some Kid :P Personally I'm not willing to save the relatively small amount of money on TTL by buying from random sources. It's especially infuriating when you're building something for the first time (prototypes, someone else's project you've never put together, etc.) and it turns out to be a dead 25 cent chip. Thanks, Jonathan Well the pal programmer I have does test TTL, a handy option, for junk box stuff. I tend to have a bad habit of putting in parts upside dowm or the wrong programmed part, for the simple fact DARK plastic hard to read in most homes with dark gray labels.
[cctalk] Re: typical IC kits on Amazon and elsewhere
On 2024-03-30 6:10 p.m., Jonathan Chapman via cctalk wrote: Standard TTL 74XXX is drying up rather quickly. Futurlec still has some TTL but 7404s are all gone. Even LS is hard to find. Ours comes from Mouser, between two part #s they have over 7,000 74LS04s in DIP packaging in stock. Didn't check ACT, HCT, or ALS. I don't think we've had a 7400 series part that we couldn't just order off Mouser in recent history, and we're usually buying QTY 100. Thanks, Jonathan I checked mouser (canada) again. After about 3 pages of garbage matches, I found some 7904's in DIP packages, only a few 100 in stock. TI and Motorola sell 74LS541's but only the Motorola part has Vin Low of .8 volts. TI has .6 Vin low. Are there any more part differences between TI and other digital logic.
[cctalk] Re: typical IC kits on Amazon and elsewhere
On 2024-03-30 4:27 p.m., Will Cooke via cctalk wrote: I'm not clear on whether you mean some specific chips or in general, but here is my experience. For things that are in current production or recently discontinued, I have had extremely good luck with Chinese suppliers either from Amazon or Ebay. For things that are long out of production, such as 1802 (normal, not SOS) and 6502 processors, I've heard way too many horror stories so I look to ebay for new old stock or used from US or sometimes European suppliers. Again, I've had very good luck. In fact, I can't remember every getting any bad ones. YMMV Will Standard TTL 74XXX is drying up rather quickly. Futurlec still has some TTL but 7404s are all gone. Even LS is hard to find. Ben. Still designing that vintage computer Newer is not always better.
[cctalk] Re: Amoeba OS
On 2024-03-28 5:50 p.m., Fred Cisin via cctalk wrote: OTOH, spammer mailing lists, and leaked personal and trade secrets seem to last forever. You forgot Mickey Mouse. -- Grumpy Ol' Fred ci...@xenosoft.com
[cctalk] Re: recreating old computers [was: Paper tape in casettes...]
On 2024-02-27 3:09 p.m., Paul Koning via cctalk wrote: On Feb 27, 2024, at 4:49 PM, CAREY SCHUG via cctalk wrote: Religion warning: I was a mainframer. Since at any practical budget, they can only be emulated, Dumpster diving is a 0 dollar budget. People could afford the APPLE II, 8080 S-100 bus, SWTPC 6909. I assume with careful shopping one can rebuild them for about the same price, in small quanities. Power supplies require harder to find parts. Main frame rebuilding is costly, but I suspect the real cost is I/O that can't be duplicated. A hardware emulation using microcode to me is real computer, a windows fly by night emulation is not, as the base platform is too unstable. Depends on your definition of emulated. Is an FPGA version merely an "emulation"? You might say yes if it's a functional model. Arguably no, if it's a gate level model. I have bad luck with FPGA's, too many timing issues with routing. I have better luck with a 2901 4 bit alu and some support logic mounted on a small pcb. Suppose you had schematics of, say, a KA-10. You could turn those gates into VHDL or Verilog, and that should deliver an exact replica of the original machine, bug for bug compatible. That assumes the timing quirks are manageable, which for most machines should be true. (It isn't for a CDC 6600.) paul The IBM 1130 is also a pretty scary machine inside. The blog is here. https://rescue1130.blogspot.com/ Ben.
[cctalk] Re: Paper tape in casettes...
On 2024-02-27 1:13 p.m., Doug McIntyre via cctalk wrote: On Tue, Feb 27, 2024 at 11:10:34AM -0700, ben via cctalk wrote: PS: With low cost Chinese PCB's and vintage parts, why are people not building real hardware replica's of interesting machines. But they are.. I can't tell what you'd find interesting since the list is pretty wide. Anything not APPLE or IBM or DEC or a PI-emulation for a home brew computer. I've got an Apple I replica board that someday I intend to populate and get running. 1) Get a good power supply 2) hack in a 6809. 3) get a good power supply. You've got the ReAmiga project producing new boards for using up old parts on broken boards. https://www.reamiga.info/?page_id=36 One thing that I find interesting (although I'd never do it), is a board to emulate a 68000 CPU at much higher speeds running barebones emulator on a Raspberry Pi. Aimed at Amiga A1200 again. https://wiki.amiga.org/index.php?title=Pistorm32-Lite I've put together my IMSAI 8080 frontpanel kit, with the CPU emulated on an ESP32. https://thehighnibble.com/imsai8080/ I had z80/s100 kit once, but the power supply failed taking every thing out. Or they are about to ship out the PiDP-10 blinkenlights kits https://obsolescence.dev/pidp10.html The CPU again emulated on a RaPi, but all new boards and plastic for the console kit I think the PI is too cheap of computer build wise for emulation of any system. It might blink your lights, but never run 20 users timesharing. > I'm not sure if anybody has ever thought about making flipchip boards themselves though. > Although they might have been.. > https://forum.vcfed.org/index.php?threads/a-general-purpose-flip-chip-adapter-board-worth-doing.1228572/ Small PCB's run at $5 each and PAL 22v10 in each could replace a lot simple cards. I would love to see a PDP-8 with 1/2 size flip chips using today's smaller logic. A good home brew computer is what I am looking for. In hindsight I want 18 bit addressing (bytes optional) and single word memory ref's. Since 2901 alu's are 4 bits wide, 20,24,28 bits are my only option for a COMPUTER not for digital controller faking it. Still working on the pro-type stage here. For test pcb's I have, good source of Chinese toggle switches with a PCB foot print. https://www.ebay.ca/itm/143887059040 Hex displays are here. https://www.ebay.ca/itm/281809099152
[cctalk] Re: Paper tape in casettes...
On 2024-02-27 9:20 a.m., CAREY SCHUG via cctalk wrote: It's not a cassette, but the PB-440 (Pitney-Bowes), renamed Raytheon 440 and its upgrade the raytheon 520 had a large reel paper tape with a bidirectional read and an "operating system" Load the os, say we want to run fortran, spin down to fortran, read the program in on 80 column cards (probably 2 pass, I don'trecall), automatically reload the monitor when done, read and execute the program from cards. Frequently used programs could be on the OS paper tape reel. btw, that computer was user level microcode. multiple "machine" definitions, with typical 24 bit word, one instruction set optimized for fortran execution, one for fortran compilation, etc (don't remember exactly, as I only programmed in the microcode of mostly 2 micro instructions per word). --Carey Where is some document ion on that machine? I finally got around to building the TTL home-brew computer I wanted from the 1970's and now I need all the goodies like paper tape and i/o that is Algol ready. :) Ben. OK I cheated using Cmos 2901's and 22v10's, but that is what I had to make the PCB layouts easy.I don't think 1 74H04 counts for making it a TTL computer. :) PS: With low cost Chinese PCB's and vintage parts, why are people not building real hardware replica's of interesting machines.
[cctalk] Re: HAPPY DEC-20 DAY!
On 2023-12-20 11:16 a.m., Rich Alderson via cctalk wrote: I wish you all a joyous Winter Solstice Festival, however you may choose to celebrate it. I like the day after, the days get longer again. Rich Ben, in the dark.
[cctalk] Re: HAPPY DEC-20 DAY!
On 2023-12-20 11:16 a.m., Rich Alderson via cctalk wrote: Happy DEC-20 Day! My late friend Mark always noted that TOPS-20 (and the DECSYSTEM-20 on which it runs) was a great improvement on its successors. I wish you all a joyous Winter Solstice Festival, however you may choose to celebrate it. Good to see it back. Rich Ben. PS for 18 days ago, the 2 http://lightning.locl.net/homes/pdp2/ PPS some say the PDP 2 was PDP 1 with a different core memory.
[cctalk] Re: Intel 4004(sp?)
On 2023-11-22 6:53 p.m., Chuck Guzis via cctalk wrote: On 11/22/23 16:47, Fred Cisin via cctalk wrote: Yup. I have vivid memories of the Intel rep telling us that not only was the 8086 compatible with the 8085, conversion could be automated through their ISIS-II based conversion program--and it would result in a smaller (memory footprint) program. To be fair to Intel,I think they did good job of encoding the instruction set for the most common sequences being shorter. 8 bit bytes only give space for byte or word instructions, not both. Prefix bytes are good compromise with the segmented 64K memory space. Data and code space are optimized for 16 bits. You want 32 bits, buy a 432. Still only 64Kb segments. Ben.
[cctalk] Re: Intel 4004
On 2023-11-20 5:36 p.m., Murray McCullough via cctalk wrote: On Nov. 15, 1971 Intel commercially released the 4004 microprocessor which some consider to be the first. Nonetheless, even if not in agreement, it made possible the instrument which drives the classic-computing industry or at the very least our hobby! Happy computing. Murray 🙂 https://retrocomputingforum.com/t/swiss-physicist-builds-complete-intel-4004-computer-out-of-smd-transistors/3738 THE DIY VERSION
[cctalk] Re: Installing DEC C on RSTS/E
On 2023-11-07 7:05 p.m., Paul Koning via cctalk wrote: On Nov 7, 2023, at 8:49 PM, Paul Koning wrote: Hi... I'm seriously rusty on official RSTS installation procedures. I'm trying to install DEC C using the C_V1_2.tap file from the bitsavers bits/DEC/pdp11/rsts directory. It's actually a TPC file, in spite of what the extension suggests. Once I supply the correct format, SIMH recognizes it and RSTS can see the tape contents. Then I try @[0,1]install c81. Point to the tape, answer the destination, and then it asks me for the "library" tape and complains when I give it the C tape again (labels don't match). So what is it looking for? Does anyone have the C installation procedure handy? paul Never mind... (a) C81 is COBOL (!!) not C. And I found the C installation manual on STUPI. Off & running now. paul Come one, don't hide you are a CLOSET COBOL PROGRAMMER. Will COBOL (C81) run on a regular 11, or does it need to be upgraded?
[cctalk] Re: The World Wide Web
On 2023-10-02 4:36 p.m., Rick Bensene via cctalk wrote: Mike wrote: ... Gawd, I still remember those numbers, some 60 years later; so why can't I remember my thirty-year old cell phone number... Because you rarely, if ever, call it. ;-) I never could figure out how to call myself, so I have no need to remember it. BTW the last time I have seen a phone book was about 25 years ago.
[cctalk] Re: The World Wide Web
On 2023-10-02 1:15 p.m., Fred Cisin via cctalk wrote: On Mon, Oct 2, 2023 at 5:18 AM Stefan Skoglund via cctalk wrote: The main problem with that lorry hurtling down the freeway is latency. I need to move 1 PB . how long will it take filling and packing enough IBM LTO-9 tapes to send 1 PB ? How long does it takes to fill 1 tape with 18 TB ? On Mon, 2 Oct 2023, KenUnix via cctalk wrote: Back it up to floppy diskettes. HaHa. Sorry I could not resist. Far too unstable and prone to damage and data corruption. Use dead-tree technology of cards or paper tape. If you use cards, put diagonal sharpie marks on the decks, to facilitate visual re-ordering after the crash on the freeway. -- Grumpy Ol' Fred ci...@xenosoft.com Also EAST / WEST , in case of data collision. :)
[cctalk] Re: Good C to FPGA/PLA compiler
On 2023-09-23 12:36 p.m., Paul Koning via cctalk wrote: On Sep 22, 2023, at 9:30 PM, Martin Bishop wrote: Paul I endorse your point regarding Lattice's gouging. Support for anything prior to the XO parts now costs a significant premium. Their XO2 parts are the most useful to this community - free tools and 0.5 mm pitch, e.g. 100p & 144p - not dense but usefully large, 3v3 IO and agricultural assembly. The Xilinx free tools no longer have license files, which was how Lattice cut us all off at the pass. The current Vivado ML Standard Edition (tools to normal people) are free up to the XC7Z030 - which is a fairly serious device. I have a PDP-11 and space to spare running in the markedly smaller XC7Z010; 16b / no MMU, most of the 45 instruction set. FPGA are (organically) memory poor - perhaps because the access time is ~3 ns. I should think you would be in with a chance of fitting the 6600 logic, however on a '30 you have 265 x 4 ki by BRAMs = ~1 Mi By, if more is required either a dedicated external memory device or DMA to/fr DRAM would be required. The 6600 model I'm building is a gate level model, so it is cycle-accurate, but also large. I'm figuring several hundred thousand gates, which makes sense if you consider the module count for a 6600. A large enough FPGA for that seems to have enough on-chip memory for both PP and CP memories, leaving only ECS as off-chip. That's helpful because both PP and CP have tightly constrained cycles; DRAM would be nearly impossible to make work, though SRAM is doable. paul I say get the memory first, who knows what you need will be around later. I wish you good luck, as FPGA software does what it thinks is right, not what you think is right. Ben.
[cctalk] Re: Good C to FPGA/PLA compiler
On 2023-09-22 3:16 p.m., Mike Katz via cctalk wrote: Martin, The debug board will need to have the following functionality: 1. Read and write to/from memory when the CPU is running using one cycle data break (DEC's version of DMA for the PDP-8). Single Cycle DMA requires some interesting signaling, including putting the priority on the data bus during part of the cycle. 2. Read and write to/from memory when the CPU is halted using front panel emulation (something totally different than one cycle data break unfortunately) 3. Handle 4 breakpoints (based on address, data, R/W and count) and signal the cpu to stop. I don't know, yet, if there will be enough time in the CPU's instruction cycle to top the CPU before the fetch of the next instruction. If this cannot be done in hardware than a much more crude break point system can be done in software. 4. There are 96 active signals on the PDP-8/E's Omnibus. I expect to need most or all of them for this project. 5. The Omnibus is an open drain, active low bus where +2.7V to +4.5V is a zero and -0.5 to +0.4V is a one. I don't necessarily need a 5V tolerant gate array but what ever I use to interface to the bus will need to be. A full description of the Omnibus can be found here: https://bitsavers.org/pdf/dec/standards/EL-00157_00_A_DEC_STD_157_OMNIBUS_Specification_Aug76.pdf Coding the break point system in some kind of parallel C like language seems way easier to me than to write this in gates. I don't have a clue how to design the count registers. I need to get #'s 1 and 2 working first and then I can dive into #3. Thanks. Hexadecimal displays til311, (pulled DIS1417's) can be found on ebay for about $5 not counting shipping. This way you have easy to read hex or octal numbers.
[cctalk] Re: Good C to FPGA/PLA compiler
On 2023-09-22 12:34 p.m., emanuel stiebler via cctalk wrote: On 2023-09-22 12:04, Mike Katz via cctalk wrote: I'm working on the design for an Omnibus (PDP-8/E) debug board and I am not very good at circuit design. I know there are programs that will compile something that looks like C into Verilog/VHDL/Abel/Etc for use on some kind of large (more than 64 pins) programmable logic device. There are still some 84pin chips out there(Altera & Xilinx). Sometimes they are pulls, or some 5V tolerant xilinx xc95l Can any of you recommend a good C like tool for programmable logic? Stay away from them :) At the end, you will spend as much time learning the differences (as it is not real "C") so invest the time in learning system verilog or VHDL. VHDL is a little more verbose, system verilog lets you shoot in your foot much easier. I hate both. You can't shoot yourself in the foot, because you can never figure where the feet are with all that verbose. If you just like to "debug" the bus, get an FPGA & some level shifters, very easy to do ... I use ADHL. It is vender specific, but I can figure out the logic. FPGA's have too many vender specific features,to go from one brand to the other. Schematic capture, is the other option. One gota with FPGA's, flip flops only have asyncronus clears, not preset.
[cctalk] Re: Good C to FPGA/PLA compiler
FPGA's tend to be ALL 3.3 volts or less today. Cmos 22v10's are nice chips to program that is still working at 5 volts. FPGA's also have high learning curve to catch the bugs and gotya's. I got tl866 ii + programer and it works great under windows, with wincupl.
[cctalk] Re: For Fred, especially: "Everything I know about floppy disks"
On 2023-09-11 10:43 a.m., Paul Koning via cctalk wrote: On Sep 10, 2023, at 6:24 PM, Fred Cisin via cctalk wrote: On Sun, 10 Sep 2023, Will Cooke via cctalk wrote: I make an official motion that Fred write his own "Everything I Know About Floppy Disks" page / book /encyclopedia. I suspect that what is inside his head is the greatest collection of knowledge about floppies on the planet. Fred, you will be paid with great admiration and appreciation. Sorry, all I can offer. :-) Anyone with me? 1) Chuck Guzis knows FAR more than I do about floppy disks. Tony Duell (ARD) knows FAR more than I do about disk drives. 2) It is now so far out of date that, Who would want it? (besides a few here) Anyone who wants to resuscitate either old drives, or recover data from old disks. There is a lot of such data... Also, history is important. Not always in obvious ways, but if it's lost it tends to be very hard to recover. One of my favorite examples of old history is the Ph.D. thesis of Gauthier van den Hove (U. Amsterdam, a few years ago) analyzing in extreme detail the world's first ALGOL-60 compiler, by Dijkstra and Zonneveld. Why bother? Well, for one, because it wasn't just the first compiler but the place where a whole bunch of later-standard techniques were first invented, and understanding the origin of things and what problems they solve and why they do it that way can be surprisingly important. paul Did Algol in general have memory leaks?,or is just C and Windows.
