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Free: 8-inch drives, S-100 expansion in OC, CA

by tosteve＠yahoo.com

For your eyes only: http://popbottlecaps.com/temp/S-100.jpg http://popbottlecaps.com/temp/drives.jpg -- Two different 8-inch floppy drives, physically in great condition, operational status unknown. -- An S-100 expansion chassis Included at no additional charge: -- VersaFloppy S-100 card w/ manual -- ExpandoRAM S-100 card (0K installed) w/ manual Free for Pick-up preferred! Located in Aliso Viejo, CA 92656

16 years, 2 months

Sanyo CP/M machine and Macintosh IIfx

by dbetz＠xlisper.com

These machines have been claimed. Thanks for all the interest! ------Original Message------ From: David Betz Sender: cctalk-bounces at classiccmp.org To: General Discussion: On-Topic and Off-Topic Posts ReplyTo: General Discussion: On-Topic and Off-Topic Posts Subject: Sanyo CP/M machine and Macintosh IIfx Sent: Feb 28, 2010 11:47 PM I have a friend who has a Sanyo MBC-1000 and a Macintosh IIfx with both a two page monochrome monitor (nicknamed the "Kong") and a 13" color monitor that he'd like to pass on to someone who will appreciate them. The catch is that they are in the San Francisco Bay Area and would need to be picked up within the next few days. I am in the area right now and could help with the pickup but I am leaving the Bay Area on Friday. If anyone is interested in one or both of these machines, please contact me off list. His description of the Sanyo is: "Sanyo MBC-1000. I've got manuals and software, including Aztec-C and BIOS source. The computer itself is very solid and was in perfect working condition when I last used it." If I don't find someone to pick up these machines in the next few days they will likely go to a recycler. Sent from my Verizon Wireless BlackBerry

16 years, 2 months

Museums

by js＠cimmeri.com

Rob Jarrat wrote: > If there were no interest in things that pre-dated our own lifetimes then > there would not be any museums. Of course, but that wasn't my point. My point is that I observe there to be, in general, LESS interest in collecting items that predate our own existence. For example, I know many more people who own classic cars like Mustangs simply because they always wanted one while growing up, or maybe had one... than those collectors who own Ford Model Ts. You could make the argument that Mustangs are more readily available, but that wouldn't be true. It's just that few if any those Mustang owners have any interest in Model T's for any number of valid reasons. So, I'm drawing a distinction between personal nostalgia and emotional response, vs. collecting purely for historical enjoyment or purposes. Rob Jarrat wrote: > The peculiar problem faced by computer > history is perhaps the frenetic pace of computer development, which has > meant that historically interesting computers are not generally recognised > as such because they are still relatively recent and become obsolete so > quickly that they are discarded far too readily. Excellent point. Which leads to wonder if only the early computers -- when development moved slower and there were far fewer models in existence -- will remain the collectible ones. I don't see any computers in most of the 90's, and none at all from 2000 onwards that I'd ever want to collect. Wonder how others feel? Will a Dell PC ever be collectible? Are Apples the only ones that might stand a chance? Are all computers now merely appliances with zero personality? John Singleton

16 years, 2 months

VAX graphics

by bqt＠softjar.se

Al Kossow <aek at bitsavers.org> wrote: > On 2/25/10 12:56 PM, Richard wrote: > >> > Bottom line for me is that this looks like a 3rd party memory-mapped >> > framebuffer > > I'm not convinced. There was no sign of it in the machine room. There is nothing visible in the machine room for a graphic subsystem. It's all in the Unibus box, with just a couple of cables coming out. > I still think it is a raster terminal. The repaint speed is consistent > with that. I'd definitely say no to that. I was working at DEC in 1986. At that time, the VT241 was the hottest thing DEC had, and it could do bitmapped graphics. But let me tell you how long it took to just get a picture uploaded on that terminal, and then we are talking much lower resolution, and fewer bitplanes. Admittedly, the DEC sixel graphics format wasn't the most efficient, but you at least transferred 6 bits of graphic data for each byte, giving it a 75% efficiency. You would have had to wait almost forever to get a picture like in the video over a serial line at 9600 bps, or even 19200. And once again, no faster serial interfaces were available on a Unibus machine. (Nor did any terminals appear to go that much faster either.) Just make a small calculation. Let's assume a resolution of 640x480, with just 8 bits per pixel. That would mean approximately 300Kbyte of data to transfer. At 19200 bps, that would take 160 seconds to draw one picture. (Assuming all bits were actual data, and no overhead.) Almost 3 minutes... This is easy math, if people just try it. :-) And I dare say, that picture have higher resolution, and more depth than my simple calculation above used. Johnny -- Johnny Billquist || "I'm on a bus || on a psychedelic trip email: bqt at softjar.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol

16 years, 2 months

UV-Proof/resistant Eprom labels.

by geoffr＠zipcon.net

Anyone know of a source for these? I had been using diskette write protect labels but the only ones I have left no longer want to stick well :(

16 years, 2 months

Bootable Model III disks...

by alhartman＠yahoo.com

I checked with a friend whose memory is better than mine. A TRS-80 Model I can duplicate bootable Model III diskettes. The Model III disk controller cannot produce all the address marks the WDC 1771 can, so a Model III cannot duplicate a Model I diskette if the OS or bootcode is dependent on having those address marks present. So, anyone with a Model I who has good copies of Model III OS disks should be able to help the poster. I'd make several copies of each just to control for the age of the media and different drive alignment. Do one drive 0 to 1 and the other drive 1 to 0. My system isn't setup yet, else I'd volunteer. Hopefully, I'll have it setup in a couple of weeks. Al

16 years, 2 months

SDS Sigma 7 sighting

by james＠jfc.org.uk

I just watched Season 1, Episode 3 of the Monkees where they have several shots of an SDS Sigma 7. This was in 1966, so it can't have been long after the release of the Sigma 7. I'd not seen it mentioned here before and I thought some might be interested... http://www.starringthecomputer.com/feature.php?f=333 -- James F. Carter www.jfc.org.uk www.podquiz.com www.starringthecomputer.com

16 years, 2 months

VAX graphics

by bqt＠softjar.se

"e.stiebler" <emu at e-bbes.com> wrote: > Johnny Billquist wrote: >> And I dare say, that picture have higher resolution, and more depth than >> my simple calculation above used. > > No, it should be just 512x512x8. Don't forget that you are watching > youtube in a lousy resolution. You are right. She even says in the beginning that it's 250,000 pixels. Assuming they take a little liberties to simplify things, that would mean 512x512. Looking at the first perspective city picture, you can see that he has a palette of 256 shades to blue to pick from (ranging from black to white). It might be that the graphic system have a color palette then, since obviously, there are other colors than blue possible, but none others are shown there. Or else they have a 24 bit pixel depth, which would be very impressive. But any way you look at it, my comment still stands. With a serial line running at 19200 bps, it would take about two and a half minute to draw a picture, at the best of time. I dare say we can safely assume it's not a serially connected terminal (even ignoring that I don't think I've ever seen or heard of a serial terminal with bitmap graphics with a resolution close to this). Looking more at the video. There are no visible clues at all that I can see as to who actually manufactured the graphics system. The system definitely are running some kind of Unix, though. Anyone who recognize the tablet? It is after all in focus quite a lot. > And we used a grinell system 1981 already (pdp11) which had 512x256 (not > sure it was 512x512). 8 bit is sufficient to show what he is doing on it. Never heard of grinell. But I have a VSV21 here. 640x480 pixel resolution. Unfortunately only 4 bitplanes. But it's a very fun graphic system for the PDP11 anyway... And later than 1981, but made by DEC. Oh, and that's for the Q-bus... Unibus graphic systems are rarer... Johnny -- Johnny Billquist || "I'm on a bus || on a psychedelic trip email: bqt at softjar.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol

16 years, 2 months

Barden programming books (was: Re: TRS-80 bootable media request)

by ethan.dicks＠gmail.com

On 2/26/10, Mark Tapley <mtapley at swri.edu> wrote: > At 17:20 -0600 2/25/10, Mike L. wrote: >>"More TRS-80 Assembly Language Programming", by Bill Barden > > A comment and a question: I found on eBay the CoCo Assembly > book by the same author. It's clear, an enjoyable read, and does a > good job of introducing programming, the debugger/assembler > implemented on the cartridge, and 6809 assembly language in a simple, > easy-to-understand progression. I may have to keep my eyes out for that one. I'm much less informed about the 6809 than any of the other contemporary processors. > However, it seems to me to give really short shrift to what > the 6809 designers considered to be very important features of the > processor. Position independent code is barely touched on, there are > a lot of what looks to me like kludgy programming techniques, the > most advanced software-management tool discussed is a flowchart (and > then there's no useful example of how to use them), the multiple > pointer registers are abused as 16-bit counters rather than as > indexing pointers, and there are many similar examples. Hmm... I haven't read anything by Barden, so I'm merely commenting on your comments, but I do remember that back in the day, besides a "better" register scheme, the one thing that really made the 6809 stand out (from my 6502 world) was its ability to render position-independent code. I didn't need it often when I was programming the 6502 daily, but occasionally, I did wish for it. Perhaps the lack of attention to that in the book is due to a lack of perceived utility for it? When the 6502 and Z80 and 6809 ruled the earth (or at least the hobbyist corner of it), multitasking operating systems weren't the norm. I know OS/9 stands out, but until you jump up to early UNIX super-micros, there's not much else in the field that was commonly available (the PDP-8 had RTS-8, but compared to a basic OS/8 setup, RTS/8 was strange and rare). The vast majority of micros had "operating systems" (by a very wide definition) with fixed-position memory maps. There was little need to be able to shuffle your code from one spot in memory to another. Even on larger systems, like the PDP-11, MMU hardware did that sort of mapping for you (despite the fact that PIC is easy to write for the -11). As for the lack of "advanced software-management tool[s]", most of the books that I've read from the late 1970s and early 1980s fall into that category. I don't think I learned anything "better" than flowcharts and coding sheets until I hit the minicomputer world in the mid-1980s (it sure wasn't any different when I took my first programming course in college in 1984 - flowcharts were a mandatory part of the homework and were graded quite rigorously). > Does anybody else have the same take on this? I was thinking > about using it to teach programming to one or more of the kids, but > it seems to me that I'd rather find something a bit more > structure-oriented, and less likely to use "tricks". By the late 1980s, I remember a change in the weather with articles in Amiga-centric magazines on programming the 68000. See if you can find Transactor magazines (or PDFs of them). Those might be "modern" enough in their approach to feel more friendly. The instruction set's not the same, but code organization and concepts are analogous. > Am I just spoiled from having read the 6809 programmer's > guide and the (somewhat snooty-sounding) Byte article on 6809 design > and introduction? Perhaps. With 1970s docs, my feeling of remembering those days is that 8080 and Z80 tutorials and guides were "stiffer" than 6502-related material, but I'll easily admit those memories are somewhat biased because I spent lots more time seeking out and reading 6502 publications in depth. The 6809 stuff, though, kinda went by unexplored by me since I had no hardware to tie to it. -ethan

16 years, 2 months

flowcharts and teaching programming/was Re: Barden programming books

by c.murray.mccullough＠gmail.com

I began programming IBM, CDC and Amdahl machines in June 1970. All assignments at the Computer Institute of Canada were graded according to the accuracy of the flowchart and the initial box as Chuck states. COBOL and other languages employed at that time employed gotos; it was a sign of sloppy programming according to purists and professors/instructors but gotos usually solved complex junction problems in an elegant fashion. BASIC and 'Small-C' used them to the same effect in the microcomputer world of late 70s. Early programming books are getting scarce yet magazines of that era had programming projects and got many of us interested in advanced programming versus machine-language programming; it beat flipping switches and assembler programming of early to mid-70s machines! Murray--

16 years, 2 months

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