[cctalk] Re: MS-DOS
On 7/31/2024 7:25 AM, Liam Proven via cctalk wrote: On Wed, 31 Jul 2024 at 06:14, Jim Brain via cctalk wrote: In the interest of facts, I don't think this is correct. Windows NT 3.1 utilized the Windows 3.1 UI look and feel https://en.wikipedia.org/wiki/Windows_NT_3.1 Windows NT 3.5 continued the 3.1 look and feel. https://en.wikipedia.org/wiki/Windows_NT_3.5 OK, true but misses out a major release, the best one of NT 3.x. I think it would be simpler to say: NT 3.1, 3.5 and 3.51 used the Windows 3.1 UI. NT 4 used the Windows 95 UI. I was trying to be a bit pedantic, since I was correcting information in the previous posting. I honestly did not remember 3.51, and I was not sure if 4 used the WIn95 UI or a facsimile of it built from some of the same source. Windows 2000 used the same UI as Windows ME: it's a modified updated version of the "Active Desktop" from Windows 98. I was not aware (or, maybe I was, but it's been long enough I forgot) Windows 2000 was supposed to unify the OS variants, but it didn't quite make it (though I think W2K moved the graphics subsystem into the kernel for better performance), No, that was NT4. I think you're referring to the GFX subsystem move, and I stand corrected. If you're referring to NT 4 being the unified OS, I would disagree. and Windows XP was the first unified OS It wasn't really "unified" in any way. That was marketing spiel. A poor choice of words. I did not mean to imply the code was merged, but that they had tried to offer feature parity in the WinNT tech. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: MS-DOS
On 7/30/2024 6:58 AM, cz via cctalk wrote: But Windows 2000 was a re-architected version of NT that people hated because of the GUI. So they dusted up the GUI with Windows 98's stuff and released it as XP. Rest was history In the interest of facts, I don't think this is correct. Windows NT 3.1 utilized the Windows 3.1 UI look and feel https://en.wikipedia.org/wiki/Windows_NT_3.1 Windows NT 3.5 continued the 3.1 look and feel. https://en.wikipedia.org/wiki/Windows_NT_3.5 Windows NT 4.0 utilized the Windows 95 look and feel, as did 2000 https://en.wikipedia.org/wiki/Windows_NT_4.0 https://en.wikipedia.org/wiki/Windows_2000 Thus, I believe the UI hate evaporated before Windows XP. I remember using 3.1, 4.0, and 2000. As I recall, I loved the stability of 3.1, but the UI was old and outdated, especially when 95 came out. 4.0 offered the nicer UI, but the driver situation was still a problem, compared to the better driver support for Windows 95/98. Windows 2000 was supposed to unify the OS variants, but it didn't quite make it (though I think W2K moved the graphics subsystem into the kernel for better performance), and Windows XP was the first unified OS and the first with a 64 bit variant. Jim
[cctalk] Re: Old vintage computing magazine/newsletters
On 7/16/2024 9:49 PM, Sellam Abraham via cctalk wrote: BTW, I wouldn't be depending on Internet Archive. Not that it's going away anytime soon, but it may some day not be there. Like LCM. Sellam I was overly precise. FOr research, I use online archives of magazines. Most folks I know put the scans on a platform-specific site or two and send a copy to archive.org, so I always check archive.org first, before researching which platform specific sites might have the periodical. And yes, the statement is true for all online sources. I am sure many of us save off copies of many items that hold more than a passing interest. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Old vintage computing magazine/newsletters
I actually enjoy reading physical issues, so I keep them when I come across them. Most of my paper mag collection is mine from BITD, but I've gathered ones from other platforms and issues before I subscribed to a periodical (Compute!, for instance). If I need to research something, though, I use archive.org. And, if I had issues that were not archived (or newslettters), I'd archive them first. I would *NOT* pay $125.00 for an issue. I doubt I'd pay that for a collection of issues. But, if I saw a few for $1/issue or something, I'd buy them. Jim
[cctalk] Re: Revocable Living Trust for Computer Collectors
On 6/27/2024 10:41 AM, ben via cctalk wrote: 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. Lightening the mood a bit: I assume it's different from systems of different eras, but I remember some of the early home game consoles being in boxes at garage sales in the late 1980s for pennies. Then, in the early 2000s, I drove around to many widows' and "downsizing so I can move into a retirement apt" users' homes and "rescued" home computers. Some of the duplicate items that were obviously of value I sold, but I kept most since I didn't see a path to selling and realizing a profit. Time moved on, and companies relocated me to different states, packing and dragging all of this stuff to new homes. When we arrived in our current home, the movers moved so many computer monitors they started taking bets on how many I had (I didn't know, I just stacked them up as I rescued them). I think they tallied 44 in total. Now, of course the market for home computers has greatly expanded, and what was once given away is now worth a tidy some of money. I do wonder, though, when the market will fall back down on certain era machines. It appears classic cars (well kept and restored, of course) continue to appreciate in value, but I am not sure the same will apply to computing technology. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Revocable Living Trust for Computer Collectors
On 6/27/2024 9:36 AM, Bill Gunshannon via cctalk wrote: Bill, I empathize with your comments. As you note, to successfully realize financial value from these items, one needs to be willing to put them into the various marketplaces, potential customers need to be comfortable with you as a seller, and customers need to find your pricing reasonable. I'm a business concern and even I am loathe to try to list items I have on the various marketplaces, for the reasons you note. Some people on this list have the "presence" and patience to see good results, but I don't think many of us do. Still, as long as we're talking about those of us here pricing, packing, and selling items, I wish everyone great transactions and positive experiences. 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
[cctalk] Re: Revocable Living Trust for Computer Collectors
On 6/26/2024 8:07 PM, W2HX via cctalk wrote: None of our survivors will give a rats-arse about getting even a nickel for this stuff. All they will want is for it to be gone. They would probably even pay to have it carted away. So I don't think any economic analysis of how to dispose of a collection to maximize return is relevant. As someone who just had to recently dispose of a collection (not PC, but still), the above might be extreme, but there's truth in there. 10 garages full of collections (multiple: vintage collectible cars, old tools, washing machine engines, collectible farm equipment, old growth oak pulled from houses, timbers from 1900 era cribs and sheds, record players (Victrola, etc.), vintage kitchen appliance, etc.), interspersed with nominal materials and some junk. https://www.facebook.com/media/set/?set=a.5088326641182317=3 Tens of thousands of square feet of stuff. Too packed to easily auction In a word, overwhelming. Being tech savvy, one could look some things up, but even that task is overwhelming. You can implicitly know the Maytag engines were worth money, but assigning value to most items is hard. Some of the very big items were easy to parcel out (the automobiles, etc.), but the tools, lumber, appliances, etc were nearly impossible to fathom. The wife could not even bear to go to the largest building (~6000 sqft), but all of it still being there stressed her out, on top of grieving the loss of her partner of 50+ years. She doesn't need the money, and looking at the items just brought back memories of trips they'd taken to pick things up. Some of the purchases were good memories, and some were not (they sometimes disagreed on whether to buy an item). Who wants to deal with all that? On the other hand, the presence of the items was comforting to the youngest daughter, who spent hours each year tagging along to buy items and build the collections. Cleaning out the locations meant removing the one final memory of her father. And, some of the properties were garages adjoining rental homes that needed to be sold, so delaying the cleanup was delaying the sale of the properties. I would not wish this on anyone, even my worst enemy. As much as it hurt, someone had to go in, take stock of what was important, and call cleaners to take the rest to the trash/recycling center. Knowing full well some irreplaceable and incredibly important or valuable items ended up in a landfill. There was simply no other way to deal with this. And, it had to be done quickly, both to free up the properties for sale and to "rip off the bandaid" on feelings from the youngest daughter. I don't know if the Revocable Living Trust is the right mechanism, but I can say that just leaving this to your loved ones or your children is almost an unforgivable offense. If you care for your friends and family at all, I beg each member of this list to find a way to document your items and what you'd like done with them after your passing. If they choose not to follow your wishes, that's on them, but leaving this activity solely to them is unconscionable. If I had a book or some papers (or even a video) noting what we of interest/importance, and what didn't really matter, I'd have felt so much better about the process. Doing the work was lots of work, but it was not nearly as hard to making decisions about what to care about, and knowing that mistakes were made and there was no way to fix them. If any of you want money from your collection, pull up your pants and sell it off while you're still around. Buyers will enjoy your stories about the items and you can gain some satisfaction seeing the seeds you plant dispersing your collection. But, don't harbor any delusions that keeping it is going to be a windfall for your family when you depart. It's not. Dad, I loved how much collecting meant to you, but you left a huge mess to clean up and it's a shame it's the last thing I'll remember about you. Jim
[cctalk] Re: What to take to a vintage computer show
On 5/1/2024 9:21 PM, Fred Cisin via cctalk wrote: Bring lots of business cards. Even if you aren't running a business, it's a lot better than standing there writing your contact information for everybofy that you want to stay in touch with. Well, or a couple pieces of paper with QR codes for your web site, or email address, or however you want to be contacted. I agree writing stuff down is nonsensical. paper, pens, pencils, post-it notes, stapler, duct tape, voltmeter, batteries, flashlight, cash, blank disks and memory cards, screwdrivers, vise-grips, hammer. Even if none of those fit in with your plans, those items will help enormously to deal with unexpected situations. travel USB cords (you never know) a long power strip with multiple taps. 6-10ft if you can. a few extra of the power cords like goes on newer PCs and such. You may need them as-is, you may need to cut one and hard wire it in. I have tons of them around here, so a few in the box is no big deal. wire stripper, side nips. In fact, if you are electronically minded at all, I'd throw an old soldering iron, a bit of solder, wick, needle nose pliers, as well. I am literally packing for a show tonight, and I am carrying all of the above. My paper, pens, pencils, post it, duct tape, batteries, cash, blank disks, memory cards, blank CDs, blank DVDs, small ethernet cable, small USB cables (the rollup kind) are all in my computer bag, so they go everywhere, as well as earphones, stereo splitter, a few checks, travel power supply for my main laptop, extra travel mouse, USB pen drives. travel LCD projector a few RCA patch cords (work for audio or video, though I normally bring home computers, you may not find as much need) signage I tend to bring some essential electronics/sockets/switches/wire as well The computers and peripherals I intend to show. Just reaching out to anyone who has exhibited at a vintage computing festival before. After years of only being able to watch others attend the ones that happen in the US, we are finally getting one in BC here. Super excited. I was invited both to speak and to exhibit, and they even got me two tables which is awesome. Like, how do you prepare for these things? What things that you didn't think of going into your first show do you wish you had? If you are doing a presentation, finish it before you get there, if at all possible. There's always people to chat with and other things drawing your attention away while at the show, and doing a presentation while at the show is always hard, if not impossible. I've done, but I do not recommend. As well, just like with any audience, ensure your prez is interesting. Try it on someone else first. Don't read the slides if that's your medium. QR code for more information is nice. I have a pretty eclectic collection, and some really rare stuff (like my Mark-8s) that I'd love to bring but am hesitant about due to the risks of transportation damage and theft (from the car mostly, not the convention itself). Just trying to decide what to bring and how focused to be in terms of theme. Maybe for the first one, be a bit conservative. I've taken some high value rare stuff to shows, but you have to pay more attention to those items before, during, and after the show, and I think you'd like to enjoy the show for the moment. Whatever you bring, make sure it is doing something. Looking at a bare computer not doing anything is not an interesting exhibit. I've been guilty of this, but it's still true. Games are always a good draw, even if that seems like cheating. Now, off to finish packing. Brad -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Last Buy notification for Z80 (Z84C00 Product line)
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
[cctalk] Re: Last Buy notification for Z80 (Z84C00 Product line)
On 4/20/2024 9:55 AM, Jon Elson via cctalk wrote: On 4/19/24 21:07, Fred Cisin via cctalk wrote: Gee! Have sales gone down? One more reason to use the 8080 subset when writing CP/M programs. Aren't there already some licensed second sources? Harris also made an all-CMOS plug-compatible Z-80. I used it in a low-power project. Jon This was my line of thinking... * Aren't there second/third sources for the original? * I understand the core lives on in ez80 and other lines. Is it possible to make a small PCB with a 40 pin DIP footprint and put one of these other designs on there? (I admit I have not looked at the other cores, so perhaps they can't be coaxed to act like just a Z80, just wondering). Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: typical IC kits on Amazon and elsewhere
On 3/31/2024 3:03 PM, Adrian Godwin via cctalk wrote: Has anyone had problems with LCSC ? I've not, but I have used https://www.utsource.net/ with good luck. Jim
[cctalk] Re: typical IC kits on Amazon and elsewhere
On 3/30/2024 10:49 PM, Tom Hunter via cctalk wrote: Sorry I mistyped. I meant Mouser and Digikey, not Amazon and Digikey. Whew! I was playing that Sesame Street "which of these is NOT like the other" song in my head reading your earlier post. :-) Since Digikey/Mouser/RS don't always have some of the more esoteric ICs I need, I do sometimes have to hit the secondary markets. I can confirm there are reputable places to do so, but I agree there has to be a compelling reason to forego places like Digikey. I find it telling that my non US PCBA buys all the actives from Digikey or Mouser and will consider only passives from local sources. Of course, that means I pay a US outbound tariff on the active parts and then an inbound tariff on the completed products, thus paying tariff costs twice. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Anyone have a D1 deck?
On 1/6/2024 11:30 AM, Michael Thompson via cctalk wrote: You could contact https://www.wmbt.org/ to see if they have a Bosch or Sony DEC to read the tapes. I'd encourage folks to contact the OP of the article. I just forwarded it to the list for additional exposure. jim
[cctalk] Re: Anyone have a D1 deck?
On 1/6/2024 5:55 PM, Kurt Geisel via cctalk wrote: FWIW, there is one clearly pictured in their 2023 tour photo album (https://app.photobucket.com/u/WMBT/a/095880e5-c73f-4b8c-ae16-a833b765a209/p/caee04d7-c7e4-41a5-98eb-35ce31bb77e5), followed by pictures of D-2, D-3, D-5, etc. I'd encourage folks to contact the OP of teh article. I just forwarded it to the list for additional exposure. jim
[cctalk] Anyone have a D1 deck?
https://entertainment.slashdot.org/story/23/12/30/0151241/documentarians-secure-original-reboot-master-tapes-but-need-help-to-play-them -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Tandy Model 6000 w/XENIX
On 10/19/2023 9:10 PM, Bill Gunshannon via cctalk wrote: Is there anywhere I could go where people who are playing with this system hang out? I used to have a couple of very early Model 16's and ran Xenix on them. I also worked with a couple of 6000's in a real production environment. Lately I got interested again and found an emulator that does a real good job and a bunch of rather interesting software for it. Some that wasn't around when I was doing this for a job. In one case, the package has a note that while it installs they couldn't get into it because the first thing it did was ask for username and password. Well, I figured out how to get into it and maybe there are others interested. It's nice to be able to see how real work was done back in the day. I have always wished some of the production software for the PDP-11 had survived, but at least this is a start. bill I know Discord is held in contempt in these parts, but https://discord.gg/pRPdatRA4Z Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Logic Analyzers - HP/Agilent 16700B or 1670G?
On 8/20/2023 3:23 PM, Alan Perry via cctalk wrote: On Aug 20, 2023, at 12:44, Glen Slick via cctalk wrote: Where are you located? That can have a large impact on the cost of acquiring a large 16700-series logic analyzer. For example, I have more of those than I need in the Seattle area. A local deal might work out well, but if shipping is involved that can quickly get too expensive. Oooh. I am in the Seattle area and have been thinking that I need a LA. alan The guidance about the 16XX series being bench space friendly is appropriate, as I went from a 1650 to a 16702A frame and had to devote much more to the unit, but I am still partial to my 02A frame, now filled with 333MHz LA cards, function generator, and o-scope cards. As for HPUX, Using the unit via VNC or X on my main PC just makes life so much easier and more interesting. I might be an outlier, as I specifically wanted an 02A, not 02B, because I wanted the on frame keyboard. Others might prefer the larger screen of the B. I most love the option to mix and match cards in these units. I built mine by grabbing it and a 16500 that has some cards I wanted, swapping and keeping the best, selling the rest. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Did Bill Gates Really Say That?
On 6/15/2023 12:48 AM, Zane Healy via cctalk wrote: On Jun 14, 2023, at 10:06 PM, Chuck Guzis via cctalk wrote: Well, I don't know about the 640KB quote, but he did say that OS/2 (what was to become Warp 3) had Microsoft's full commitment. (cf "The OS/2 handbook"). At the time he said it, MS was already developing NT and had not the slightest intention of honoring that statement. What I also remember is this: For the developers who paid for the advance copy of the "new OS/2" (about $3000, IIRC), MS sent out copies of NT 3.1. Under threat of lawsuit, they relented and refunded the advance payments. --Chuck When shipped, Visual Basic v1 stated that it was for Windows and OS/2. I purchased it due to this. They only included the Windows version. By the time MS released Windows 95, I had a system running Lotus SmartSuite for OS/2, which by then was owned by IBM. Lotus SmartSuite was so buggy that I saw the writing on the wall, and bought my first Mac, a PowerBook 520c. I’m typing this email on a Mac. If MS had delivered an OS/2 version of Visual Basic, there is a good chance I’d be typing this on Windows. Zane I worked for 3 years learning the internal communications APIs on OS/2 to support and enhance a common networking layer for Compuware applications called "Generalized Communications Services (GCS)" as part of the "GCS" team at that firm. The layer was used by all of the OS/2 front ends connecting to legacy OS/370 mainframe apps that Compuware sold (Xpediter, File-Aid, etc.). I used to joke that all of that skill was then useless as the world moved to NT. In reality, there are lots of similarities between the OS/2 and WinNT IPC and networking APIs, but that made for a less interesting story! :-) GCS would no doubt cause people here to cringe, but I think it was impressive for the time. It provided a common naming service (ala DNS) for protocols such as LU.2, LU6.2, Named Pipes, NetBIOS, and TCP/IP, and offered a way to simulate full duplex operation over half duplex LU2 channels. It also worked with all of the Windows 3.1X 3270 emulators of the day and offered the ability to send arbitrary length data over LU2, even with the significant constraints of LU2 screen sizes. Efforts were helped by realizing that most emulators would allow for very large screen sizes (128x128, or sometimes even 128x512, which would allow 16kB - 64kBto be transmitted in one packet). There was a "hub" defined which could seamlessly convert from one protocol to another if the sending code found out from the naming service that the receiver was on a different protocol, as the sender would send to the hub, which would convert and then send to the recipient. The emergence of TCP/IP on Windows for Workgroups, Win95, WinNT3.1, and zOS spelled the end of GCS. As a further anecdote for those caring about 370, a man by the name of Walter Falby at Compuware got so frustrated at IBM's initial TCP/IP protocol stack for the zOS environment he borrowed by Comer networking books and implemented (in 370 assembler) an entire TCP/IP protocol stack (called HCI) I think Compuware sold to customers for a while until the IBM code got better... That developer reminded me so much of the "Mel" of Internet Folklore fame. /me still has his copy of OS/2 v3 and Warp sitting here. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Getting floppy images to/from real floppy disks.
On 5/22/2023 11:25 AM, js--- via cctalk wrote: Hehe, I chuckled. I have such a machine (triple boot, DOS, Windows, Linux) PII sitting here that used to be my primary machine (hand built from cheap parts at the old Omaha, NE monthly computer show), no eBay needed. Machine does not get a lot of use anymore, but it fires right up when needed. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Getting floppy images to/from real floppy disks.
On 5/18/2023 2:08 PM, Paul Koning via cctalk wrote: As for loading in/loading out files from images, there’s likely at least something out there you can make use of. Even if there’s no host OS native software for writing directly to images, there’s almost certainly an emulator, which would work off disk images that can later be written to real hardware disks. This is why I avoid MS products. They don't offer stuff like that, which on Unix is a perfectly normal operation available via dd or other ways. cygwin has always been my friend on Wintel boxes. dd available there and works just fine. WSL can also be used, but cygwin has served me fine so far. I guess, given the thread title, I should shamelessly plug that all of you with latent Commodore 8 bit disk images can use ZoomFloppy via a 15X1/or PET drive and a USB connection to put those images onto disks. Grab one now from the store! Jim
[cctalk] Re: ST-251 Data Recovery for Glenside Color Computer Club (GCCC)
On 5/16/2023 4:43 PM, dave.g4...@gmail.com wrote: Jim, I would ask on here:- https://groups.google.com/d/forum/mfm-discuss to see if any one has one of these https://www.pdp8online.com/mfm/mfm.shtml which will image an MFM disk so you are not re-reading and probably damaging your original, an can then analyse the content at your leisure That was my thought as well. Image the raw data, and then work on decoding. Dave Gesswein already reached out. Jim
[cctalk] Re: ST-251 Data Recovery for Glenside Color Computer Club (GCCC)
On 5/16/2023 4:05 PM, Dennis Boone via cctalk wrote: > At the most recent CoCoFEST!, I brought home the old Glenside Club > Computer Hard Drive. The mechanism is an ST-251, and I was wondering > if someone on-list would be willing to attempt to pull data off the > drive. I have no ability to configure to read this drive type, and > the data is not precious or anything, I just though we should try to > pull it off for historical sake. The best way to approach this, given the interchange issues with MFM disk controllers, is probably to use one of Dave Gesswein's MFM Emulator devices. It'll give you a flux image that can then be decode. There may not be a decoder for the CoCo format yet, but it's probably not too far different from other common things, so hopefully it could be constructed fairly easily. The MFMEmu community seems to be willing to help with this. De David has already connected with me, and I am grateful to send the unit to him to see if he can retrieve anything. And yes, once the data is off the drive, creating a decoder should not be overly difficult. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: ST-251 Data Recovery for Glenside Color Computer Club (GCCC)
On 5/16/2023 3:54 PM, Mike Katz wrote: I'm sorry but I am not familiar with any CoCo OS hard disk formats. All valuable information, but I am not concerned about the FS format. ONce the data can be retrieved from the platters, either I or others can write some code or create a way to view the files. Mainly, I just need help getting the digital data off the HDD. Jim
[cctalk] Re: ST-251 Data Recovery for Glenside Color Computer Club (GCCC)
On 5/16/2023 3:00 PM, Kenneth Gober wrote: On Mon, May 15, 2023 at 11:21 PM Jim Brain via cctalk wrote: At the most recent CoCoFEST!, I brought home the old Glenside Club Computer Hard Drive. The mechanism is an ST-251, and I was wondering if someone on-list would be willing to attempt to pull data off the drive. In my experience, reading the data from this type of drive is dramatically simplified if you have the original controller it was attached to. If you can get your hands on it, this job will be many many times easier, and doable without special equipment. -ken I did not know that. I do have the original controller, but it's a bit complicated. The controller is a Burke & Burke CoCo HDD controller. I pulled the PCB from it. Inside is 2 PCBs. One looks like a standard 8 bit ISA card (WD1002A-WX1, no rev number), and the other is a small PCB that appears to adapt the ISA bus to the CoCo bus (4 MSI TTL and a CR2032 battery). I assume just having the ISA card would be enough... Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] ST-251 Data Recovery for Glenside Color Computer Club (GCCC)
At the most recent CoCoFEST!, I brought home the old Glenside Club Computer Hard Drive. The mechanism is an ST-251, and I was wondering if someone on-list would be willing to attempt to pull data off the drive. I have no ability to configure to read this drive type, and the data is not precious or anything, I just though we should try to pull it off for historical sake. I was not in the club when teh drive was in use, so I do not know what could be on it. I assume BBS data, but it could be anything. Happy to post to someone who wants to give it a go. If the drive needs to be destroyed to get the data, or if attempting to read the data destroys the drive, I will not hold anyone responsible. I don't even need the drive back, just data if it is recoverable. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Looking for EPROMs
On 3/27/2023 1:07 PM, Mike Stein via cctalk wrote: 68764s and 2532s are still available if you look hard enough; if you can't find any, with a couple of jumpers the unusual TMS2564 can replace both of them As can a 23XX Adapter (shameless plug, but gerbers are available for anyone to roll their own). Jim
[cctalk] Re: Knockoffs, was: Low cost logic analyzer
On 3/15/2023 10:05 AM, Ethan O'Toole via cctalk wrote: If you posted your design as Open Source, someone else producing it isn't a knockoff, it's the system working as intended. -- Chris I remember a talk by LadyADA of Adafruit at HOPE about starting a company making open source hardware and success and all that. It's easy if you have the marketing and big revenue stream, but eventually people will copy the designs. Also there are cases where multiple people have the same idea, I have projects that I started and didn't finish but I bet if I look around someone else has made the same thing and filled in the gaps. My FLOSS experience has not been all bad. Many linux distributions include tcpser or make it a package to install, and I have no doubt the OSS nature of it influenced that. I've created lots of software that others have forked, improved, and folded back in. I'm always appreciative. The same has happened with hardware designs. And, if someone takes the files, modifies the design for a different use case, I actually appreciate that. One can only itch so many scratches at once, and knowing that there are derived options for other use cases is a good feeling. Also, big HP versus USB logic analyzer. I had one of those old HP logic analyzers a while ago and it was really slow. Way easier to use the USB ones when it comes to portability and software speed. Plus easier to store captures, share data without a GPIB plotter, etc. I'll agree the HP is not my first go to when I want to debug something. But, I found I had two distinct LA needs. One was a spot or low quantity need, where 8-32 channels provided plenty of capability and simple triggers were fine (watch for a falling edge, etc.) But, the other was 40-80 lines (full address and data busses for multiple busses, along with control signals) and complex triggering was needed (start tracing when address1 = $dfea and address2 = $00ea, etc, R/W low, Phi2 high, DMA low, the second time this occurs). At least when I checked, USB options providing those features were far out of my price range. But, take nothing I've said as dissing the USB options. I literally have a unit in my carry on bag, along with some leads, since you never know when a bit of LA access will quickly help someone. It's the same with the scope situation (well, in my case, it's backwards). I *love* my Tek2465 and I'm jsut so comfy firing it up and scoping a signal of interest. But, it's not portable, so it stays on the bench. I bought a Siglent1202 when they were too cheap to pass up (at Hamvention a few years back, show special), and it offers a lot of cool features the 2465 doesn't offer. It's also more portable. And, recently the Hantek 1070A was on sale at too good a price to pass up, so I picked one up. Hantek is awesome ti throw in the box for shows, in case someone needs a scope. Siglent sits on the bench and is used for capturing glitches and such, and the Tek is my comfy scope I use otherwise. Thus, I trend to use the old school option, but I have the newer tech available since it offers advantages in some cases. That said, I may sell teh Siglent/Hantek combo and look for a 200MHz dual channel USB scope with a built in screen (requiring a PC to read the trace is not always best use) Jim
[cctalk] Re: Knockoffs, was: Low cost logic analyzer
On 3/14/2023 8:26 PM, Chris Hanson via cctalk wrote: If you posted your design as Open Source, someone else producing it isn't a knockoff, it's the system working as intended. -- Chris Yep, naive on my part. I would counter that if I had just published my designs online with a commercial license, I doubt it would have made a difference :-) Anymore, it seems people assume that if the files exist, it's OK to copy and produce. It seems witholding some of the files/designs and/or sharing with a trusted source who has permission to open source or otherwise publish it after you are no longer interested in the thing is the only way to accomplish my goal, at the expense of people who'd like to peruse the internals for personal value or fix one. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Knockoffs, was: Low cost logic analyzer
On 3/14/2023 4:48 PM, Alexander Huemer via cctalk wrote: * The main IC in a 16 channel Saleae LA is a Xilinx Spartan 6, The clones are of the older pre 2015 Cypress FX2 design, which was not easy to protect. I don't see any eBay listings for the newer stuff in clone format. I do see Logic8/Logic16 clones for sale, but they are not the Xilinx variant. * The Saleae host software doesn't attempt to validate that the hardware it talks to is genuine even though that would be trivial to do as well. When version 1.1.9 came out, they did just that, to try to protect the unit. The backlash was incredible, since most of the clones had represented themselves as Saleae units, so the folks with now bricked units complained bitterly to Saleae. They removed the check under pressure. If you look at clone ads, you'll see 1.1.10+ as the app version, for exactly that reason. * No import stop of clones or anything like that was attempted by the company. I don't know how you would stop the import of clones. The design is trivial and cannot be copyrighted (the specific PCB artwork could, but the clones never use that, they are much smaller and laid out differently. The controller is loaded from the PC, so I believe the clones didn't even need to pirate the SW. * Listings on eBay, etc. of Saleae clones are advertised as "Saleae", which could easily be stopped by the company, that has happened thousands of times for other products. They seem reasonably successful. I remember in mid 2010s, there were tons of listings. Now, I see a single Logic16 (old Cypress-based clone) for $73 on eBay before I see actual used Logic16 Pro units. But, I see a ton of Logic8 and Logic16 clones under generic names that are easy to identify as Logic clones. $9.00 (for 8 ch) to $50 (for 16). Clones of Saleae devices are on the market since a long time. Saleae brought out new hardware revisions since then, so the argument 'they were taken by surprise' doesn't hold up. Is there a link where they said they were taken by surprise? I think they were in the beginning, but that was in 2014. If the quote is recent, I would agree, they've known for a while. Though a knockoff Saleae LA won't make you end up in hell. I don't think I implied it would. I do have reservations about such a recommendation in general and how it could negatively affect this community, as people apply it to other products/projects. All that said, I will concede that the current Logic pricing is steep. For the price of a 2023 Logic16Pro, I procured 2 complete 16XXX HP frames, made a fully loaded units with 2 function generators/3 333 MHz LA cards (204 channels)/100MHz DSO, and sold the extra 16500 frame with 2 100MHz+ cards onto to another community member. Maybe Sigrok and a few of the less expensive 32/34 channel options is a better suggestion for the lower end option. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Knockoffs, was: Low cost logic analyzer
On 3/14/2023 4:16 PM, Jonathan Chapman wrote: There are other things that we've chosen not to run for the same basic reason, and others that won't get open sourced. I will admit I am trending in that direction. I put things as FLOSS because I wanted the designs to outlast my involvement with the community. I thought if the design was open source and I wanted to or had to depart (including the Great Departure), the designs would continue to be available rather than disappear. But, so many people have abused that idea. Luckily, most of my stuff is not useful enough to copy and sell online... Of course, not putting it out as open source infuriates folks as well, especially those who believe in "right to repair" (I do as well, but some people are pedantic about it and will not buy anything closed). And, putting it out with a closed source license doesn't help, as people still clone it, and they don't care about the legalities of it. It's nice to support the designers in some capacity, but buying knockoffs fuels the ecosystem that creates knockoffs. I'm waxing a bit pragmatic, I guess. People gotta people, I figure. Jim
[cctalk] Re: Low cost logic analyzer
On 3/14/2023 1:00 PM, Jonathan Chapman via cctalk wrote: On HP: yes, perhaps. I used one of those back at DEC, in the mid 1980s. Nice machine, but my suspicion is that I'd run into the small memory problem again that plagues me with the Philips/Fluke analyzer I use right now. We use several HP analyzers around here, all from the 80s. Even the "small" ones are 72 channel and more than sufficient for all your old computer needs. The big ones have Ethernet and will talk X11 across the network, which is super handy. As stated previously, I agree with this. the 16500/1670X units have replaceable cards for LA options galore, and the 16717s I have are 2MB/4MB capture length. If you capture based on a 1MHz clock, that's multiple seconds of capture. If that's not enough, feel free to put a 16760A card in for 68 channels of 400Mhz timing and 64MB of storage. If you halve that and use 34 channels, you can get 800MHz timing, and I think 128MB of storage, if I read the specs correctly. You can also trigger off the 16530/31 DSO card, or the 16521/22 function generator. If X scares you, VNC is available on these, which is what I use. The trigger syntax is odd but powerful. Before getting my first HP 1650, I had an older Sony/Tektronix that suffered from the "not deep enough capture memory" issue. Haven't run into that with the HPs yet, especially the big HP 16500 series. I've found that if I'm running out of memory depth, I'm probably not hooked up right. I find I get lazy given how much I have. Probably not good practice, but it happens. I'll admit that I had higher hopes for the sigrok stuff, but maybe it's just me. I have a 34 channel LA here that can use the sigrok tools, but I've found my self continually frustrated by the entire system not working or the data not being represented well so I can debug. So, I've shied away from the sigrok in lieu of either using the absolutely simplistic (but fast to set up) Saleae App or delving into the 16500/1670X unit to get what I need. As to this comment: On 3/14/2023 3:57 AM, Alexander Huemer via cctalk wrote: The Chinese knockoffs of those are working beautifully and cost next to nothing compared to the original. $50 vs $1300. Considering how well the software works and how much memory depth you get, it is really amazing. I use one of those[1] since years with great pleasure. Those USB LAs are so cheap that there isn't a good reason not to have one in the desk drawer. I have misgivings. As a person who loves a bargain, Alexander has a valid point, and I considered adding it to my initial response (confession, as Alex does, I own one of them). But, as some who worked to bring a product to market only to see people on forums say "Skip buying it from Jim for , you can build the same thing by yourself for $ from AliExpress parts or buy this eBay knockoff for 2X$", I will admit that is somewhat infuriating. If the hobby community is not willing to pay a bit of premium to support those who bring out the products that benefit the community, the designers will get disgusted and leave. Thus, I'd say if a Saleae is something to pursue, try to buy one from them, to support their awesome GUI, and then drop by eBay and grab 2 or 4 of the knockoffs to put in your toolbox or travel debugging rucksack. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Low cost logic analyzer
On 3/13/2023 8:12 PM, Paul Koning via cctalk wrote: Gents, I've been doing logic debugging (on a fairly primitive software defined radio I designed back in 1999) with an old Philips logic analyzer. It's not bad, certainly fast enough (I need 100 Msamples/s, it can do twice that) and it's more than wide enough (I need 32 channels). But its capture memory is microscopic so I struggle to see more than one or two transactions, and I need to see more than that. Some poking around shows various USB-connected logic analyzers for quite low prices, and a number of them seem to have suitable specs. I also ran across sigrok.org which seems to be an open source logic analysis framework that can drive a bunch of those devices. Nice given that too many of them only come with Windows software. I suspect there are others that have not too expensive logic analyzers and might be able to offer up suggestions or product reviews. paul If you have 8 or 16 channels to watch, the Saleae units are absolutely incredible: https://www.saleae.com/ For more channels, I will admit I'm partial to old HP units, especially the frames. I have a 16702A here, which I love. I have 3 333MHz LA boards in it 68 channels per board, 204 channels overall. It's not quite as trivial to use as the Saleae units, but it does offer remote access via X or VNC. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] FD-55 360kB HLS spares for sale?
The USB FDC controller ICs finally arrived and I am working to clear the project desk to build a dev board. As part of testing, I'm wondering if anyone has any working FD55B drives for sale with the HLS? I am the market for 1-2 more, and I thought it'd be nice to get one for this project instead of trying to liberate one of my drives from a working machine. I see the links on eBay (a few untested HLS variants and a working non HLS one available), but would prefer a working HLS B. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Why the Floppy Disk Just Won't Die
On 3/9/2023 10:34 PM, Fred Cisin via cctalk wrote: I doubt that there is any market segment with deep pockets, with a "need" other than nostalgia. I've actually considered trying to research finding equipment to manufacture such media, and/or recreating it. Everyone needs another hobby, right? That said, in my day job, I've seen IT folks at times be their worst enemy in focusing so much energy in keeping outdated items running, only to discover a lack of support to upgrade/replace said items because they've removed the friction of staying with the outdated device/system. Part of me sees the same issue here. It'd be expensive but not insurmountable to recreate lots of media options, and even more realistic if some of the old manufacturing equipment is still mothballed and not scrapped. But, putting new floppy disk media into the market, even at inflated prices, would remove the friction IT resources have depended on to force governments and businesses to at least migrate to solid state replacements, if not fully upgraded systems. Obviously, the cost (and the fact that finding existing equipment to un-mothball is the much more realistic an option to pursue rather than trying to fabricate new equipment) is a significant roadblock, but I also hesitate for the above reason. It's almost like a few more years need to pass, to force the remaining holdouts to realize floppydisk.com and eBay and the nature of rust glued onto mylar will not exist much longer at quality levels that companies can risk. Then, I'm hoping someone with deeper pockets than I starts production :-) Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Why the Floppy Disk Just Won't Die
https://www.wired.com/story/why-the-floppy-disk-just-wont-die/ Take what you want from the article, but I thought the end paragraph, noting that Tom Persky of floppydisk.com is 73 and is only planning to handle things for 5 more years. After that, he thinks the company will not transfer to anyone. Interesting thoughts there. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: ZFS, was [... GreaseWeazle ..]
On 2/2/2023 1:47 PM, Sellam Abraham via cctalk wrote: On Thu, Feb 2, 2023 at 11:26 AM Vincent Slyngstad via cctalk < cctalk@classiccmp.org> wrote: I've also seen a work style where everything is pushed to github when "finished", but github storage limits are small and the interface is awkward to me. I've tried a few times to make sense of how GitHub works but I gave up. It's a mess. Sellam Hmm, I'd be happy to do a Zoom call to show folks. Git can be complicated, but the simpler items are easy and using the command line git connected to a github/bitbucket/gitlab repo and a simple git push and all your local data/files under control are magically on the web for sharing, if that's the goal. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: DLOAD BASIC command for Color Computer 1/2 heritage
On 1/31/2023 6:04 AM, Tony Duell via cctalk wrote: "DLOAD is the most obscure command in the Color Computer and absorbs a substantial amount of space in the ROM. DLOAD is so poorly understood because Tandy has never made the necessary companion routine, DSEND. I wonder if it was originally intended (or even used) at the factory to download a diagnostic program into the machine for final testing, or for similar use at repair centres? The IBM5150 has a similarly obscure facility to download a diagnostic program through the keyboard port (this one is sort-of documented in the BIOS sources) -tony It's always a possibility, but a dead test cart with the code would have been a far better solution, and easier to implement, as the ROM is permanent 9so to speak) on a home machine and would have had to go through more QA. I think (I might have mentioned it at the thread start) it was part of a plan for a school network. Tandy offered a similar setup for schools for the Model 1/3/4 systems, where the "host" could send programs, and the clients would load from the common host system. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: DLOAD BASIC command for Color Computer 1/2 heritage
On 1/31/2023 4:26 AM, Philip Belben via cctalk wrote: ZX80, ZX81, Spectrum, Acorn Acom, Acorn Electron, BBC Micro, etc, etc. Do you count machines like the Amstrad CPC464 which had a built-in cassette recorder? And don't forget the Commodore cassette port - used on the PET, VIC, C64, ... I didn't. It was in the email this was a reply to: On 1/30/2023 11:34 AM, Jim Brain via cctalk wrote: Lots of systems had dedicated cassette ports, but yes, CoCo has a dedicated cassette port, as does all the 8 bit CBM machines, I think the Model 1/3/4 also, and doesn't the Apple II have one as well. I am sure I am forgetting a bunch. This blurred the line between built-in cassette drives and cassette ports, since the built-in drive on early PETs became the separate drive on later ones, plugging into the same port. Maybe less so than initially thought, as early PETs had 2 cassette ports, so I think that kept people from thnking the cassette drive was some "internal only" thing. The second cassette was addressed as ,2, with the internal being ,1 Also unusual, I think, was that it didn't use a modem chip to generate tones, but bit-banged them in software. Not sure how many systems did that, but it was not a CBM exclusive. Tandy did that as well on the various 8 bit platforms it offered. Philip. -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: DLOAD BASIC command for Color Computer 1/2 heritage
On 1/30/2023 11:14 AM, Chris via cctalk wrote: It had a dedicated cassette port? Don't most cassette ports resemble a serial port, or is my wonky brain making that up? What protocols did most cassette ports use (c64/128?, IBM 5150, coco ...)? Lots of systems had dedicated cassette ports, but yes, CoCo has a dedicated cassette port, as does all the 8 bit CBM machines, I think the Model 1/3/4 also, and doesn't the Apple II have one as well. I am sure I am forgetting a bunch. I think it would have been hard to have the cassette use the serial port, because cassette needs audio tones, not RS232 levels. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: DLOAD BASIC command for Color Computer 1/2 heritage
On 1/30/2023 6:32 AM, Chris via cctalk wrote: I cam't help you. But let me get this strait. 2 cocos connected with ... a null modem cable? can send info to one another in basic? What is the corresponding send commamd? Or was this simply intended to accept data from a cassette recorder? It still seems sending data coco to coco should't be too hard. Only DLOAD was implemented in BASIC, so two CoCos would not work. As such, it did not get used and was eventually removed from the BASIC in the CC3. Cassette load was handled another way. DLOAD specifically used the serial port. And yes, sending data to CoCo is not overly difficult, they were just wondering about the provenance and history of the DLOAD command in the BASIC. Jim
[cctalk] DLOAD BASIC command for Color Computer 1/2 heritage
Over at the CoCo Mailing List, there's a archeological discussion about the DLOAD BASIC command in older versions of the Color Computer BASIC. It uses the serial port (and no doubt was designed for computer sharing in classrooms or similar), but the questions are around how it was designed and what inspiration is drew from. I infer MS wrote the code, and the protocol includes: P.ACK - Acknowledge - C8 hex. P.ABRT - Abort - BC hex. P.BLKR - Block request - 97 hex. P.FILR - File request - 8A hex. P.NAK - Negative Acknowledge - DE hex. Does that look like any protocol anyone has seen before? Jim
[cctalk] Re: Computer of Thes[e]us
On 1/27/2023 8:31 AM, Liam Proven via cctalk wrote: On Tue, 24 Jan 2023 at 21:26, Doc Shipley via cctalk wrote: This Subject: line is damaging my brain. It's such an old name, the 2nd E has worn right out of it. I mean it is the most commonly-used letter. It was always likely to fail first. Thanks for the chuckle. I admit I created this issue, I copied the name from the previous comment into the subject line under an assumption of correctness (probably not a defensible argument, but it's the one I'm sticking with) -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Restoring floppy disk images to their rightful media
On 1/24/2023 12:23 PM, Tony Duell wrote: On Tue, Jan 24, 2023 at 6:16 PM Jim Brain via cctalk wrote: On 1/24/2023 12:12 PM, Tony Duell via cctalk wrote: I've skimmed the thread about making images of floppy disks. I want to do the reverse. Greaseweazle will do this. Use the same HW setup as for imaging, but instruct the GW software to write an image to physical disk. From what I understand the Greaseweazle works by measuring the times between pulses on the Read Data line, So presumably for writing it outputs a series of pulses with the right spacing. Does software exist to turn a disk image (as in a ,imd file) into suitable timing data for this? -tony Looks like a few tools will do so: https://forum.vcfed.org/index.php?threads/a-way-to-convert-imd-to-img.1237774/post-1246165 You just need to get the IMD to be an IMG file, and then GW will create the flux and timing info from that image file. Jim
[cctalk] Re: Restoring floppy disk images to their rightful media
On 1/24/2023 12:12 PM, Tony Duell via cctalk wrote: I've skimmed the thread about making images of floppy disks. I want to do the reverse. Greaseweazle will do this. Use the same HW setup as for imaging, but instruct the GW software to write an image to physical disk. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Computer of Thesus (was: Re: Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man)
On 1/23/2023 9:04 PM, Sellam Abraham via cctalk wrote: On Mon, Jan 23, 2023 at 6:17 PM Jim Brain via cctalk wrote: On 1/23/2023 7:58 PM, Chris via cctalk wrote: That brings back memories (pun maybe intended). In the late 1980s, you could buy 5.25 DSDD in bulk for $USD0.29/disk, but you had to buy in bulk. So, clubs would buy, or someone would snag 100 or 200 and then dole them out for a bit of profit. I did that a couple times: bought 50 at a time for maybe 35 cents each? Something like that. They worked (and continue to work) great. Sellam For some reason, the whole buy in bulk and cut down to smaller sizes and sell just seemed so underworldly to me. You drove over to a friend's home, flashed a bit of cash, and someone would snag it and lay a plastic baggie of disks (literally. To save money, I remember they skipped boxes for plastic bags of 10) into your hand. You quickly went back to the car and drove away. Sometimes, the exchange happened at an event or in front of a frequented store. It felt dishonest in some way. I must have watched too many drug films/TV shows at the time. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Computer of Thesus (was: Re: Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man)
On 1/23/2023 7:58 PM, Chris via cctalk wrote: The nice thing was by the mid 80s there didn't seem to be crap disks. Some guy had a shop in some basement. Commodore stuff mostly iirc. He was selling generic didks. They were cheap, probably 4 for a dollar. I never had a problem with a single 1. Can't recall if I ever formatted them to 720k though. That brings back memories (pun maybe intended). In the late 1980s, you could buy 5.25 DSDD in bulk for $USD0.29/disk, but you had to buy in bulk. So, clubs would buy, or someone would snag 100 or 200 and then dole them out for a bit of profit. Tons of them here and still in use. -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: any COCO enthusiasts
On 1/23/2023 1:21 PM, Mike Katz wrote: On 1/23/2023 12:11 PM, Jim Brain via cctalk wrote: On 1/23/2023 11:53 AM, Mike Katz via cctalk wrote: The 6883 SAM was the "glue" that provided all of the timing and address decoding for the entire system. To reduce flicker the 6847 and 6809E memory accesses were alternate cycled. This means that they used opposite edges of the Phase 1 clock to access memory. However, this meant running the system at .8949 MHz. The SAM had the ability to run the CPU at twice that speed but this resulted in the video being disabled. Are you sure about that? The system could be sped up, which involved not refreshing DRAM, but all of the support ICs and the DRAMs are 1MHz, so I don't think 2MHz was possible on the CoCo, at least. I don't recall if that was the CoCo 2 or CoCo 3 but the system could handle 1.8MHz (with a MC68B08E CPU). The memory had to be 2MHz to handle the alternate cycling. I stand corrected: "Switching the SAM into 1.8 MHz operation gives the CPU the time ordinarily used by the VDG and refresh. As such, the display shows garbage; this mode was seldom used. However, an unusual mode available by the SAM is called the Address Dependent mode, where ROM reads (since they do not use the DRAM) occur at 1.8 MHz but regular RAM access occurs at .89 MHz. In effect, since the BASIC interpreter runs from ROM, putting the machine in this mode would nearly double the performance of a BASIC program while maintaining video display and DRAM refresh. Of course, this would throw off the software timing loops and I/O operations would be affected. Despite this, however, the "high speed POKE" was used by many BASIC programs even though it overclocked the hardware, which was only rated for 1 MHz operation. " Note that the CC3 had a speedup poke that was different and did in fact speed the entire system with video intact. The straight MC6809 (non E version) used a more forgiving quadrature clock but could not be alternate cycled. Actually, the 6809E is the Q/E clock version. The 6809(non e) is the crystal based one. Thank you for clearing up the CoCo 3, I never had one. I know the MC6887 could address and handle the refresh for 96K. I'll have to read up more on SAM. I know it can have 96 memory, but I thought is was 64kB RAM and 32kB ROM. OS9 Level II was designed by Motorola and Microware and made full use of the capabilities of the 6809 architecture. With simple Dynamic Address Translation 1MB of extended address space was available. The CoCo 3 could only do 512kB, due to the translation granularity being 8kB and the GIME DAT only have 6 bits. But, back in the day and today, there are solutions to extend that to 8 bits per translation, which brings up to 2MB. CoCo 3 based L2 OS9 only supports up to 2MB natively. There is a few > 2MB options, but OS9 can currently only use the >2MB as a RAM disk. Jim
[cctalk] Re: Computer of Thesus (was: Re: Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man)
On 1/23/2023 1:01 PM, Mike Begley wrote: Right now, I'm going back and forth on an IMSAI I am restoring. Part of me wants to do as slavishly accurate a restoration as I can, but the another part insists that there really is no such thing, really, as the whole culture around S100 was about taking the bus and extending it in a myriad of ways. I'll probably fall somewhere in the middle, but if I could ever find a CCS Z80 main board I would probably switch to that and put the original IMSAI 8080 MPU board into storage. I think this is a very important point. I have a lot more patience and "live and let live" perspective on folks that modify their systems in a way that can be returned to stock. And, I'll give a bit of a pass to folks butchering a mass produced home machine with lots of units in the market (think C64). But, modifying a limited availability machine in a way that cannot be returned to stock bothers me more than it probably should. Jim
[cctalk] Re: Computer of Thesus (was: Re: Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man)
On 1/23/2023 12:59 PM, Mike Stein via cctalk wrote: Let's face it, most of us have trouble justifying the time and money we spend for whatever reason on what is essentially useless obsolete junk to anyone outside our community. I "fell" into a situation that contains the trifecta of hobby justification. It funds itself, it allows me to play with many systems, and my lovely SO not only does not complain about the hobby, she even sends links to items for sale and/or places to visit in the hobby. It additionally keeps my HW skills in some use, which I value. Thanks for your many contributions BTW, Jim, especially in the Commodore world but much also applicable elsewhere. awww, shucks... In all honesty, I usually make this stuff to fix my system first. That other people find a use is almost an afterthought :-) Well, I also make it to figure out how things work. I find I don't really understand a system until I make a HW item for it. And, I've long held (and presented at my main job) that folks who try to understand the "under the covers" portions of technology, are the ones that excel in creative solutions to unique problems that tend to show up in IT or other tech fields. As to your soapbox, I try very hard not to judge folks for how to enter and enjoy the hobby. While I'd love to say it was just the nice thing to do, it's mainly that I've been recipient of that judgement many times. Maybe you all would believe this, but I am continually shocked by how many people will come up my demo or sales booth at a vintage computer show and aggressively complain or debate the merits of paying any attention to old systems (or related items). I mean, it's a vintage computer show. What did you expect to find there? :-) Jim
[cctalk] Re: any COCO enthusiasts
On 1/23/2023 11:53 AM, Mike Katz via cctalk wrote: The 6883 SAM was the "glue" that provided all of the timing and address decoding for the entire system. To reduce flicker the 6847 and 6809E memory accesses were alternate cycled. This means that they used opposite edges of the Phase 1 clock to access memory. However, this meant running the system at .8949 MHz. The SAM had the ability to run the CPU at twice that speed but this resulted in the video being disabled. Are you sure about that? The system could be sped up, which involved not refreshing DRAM, but all of the support ICs and the DRAMs are 1MHz, so I don't think 2MHz was possible on the CoCo, at least. There are many programs and peripherals available for the Color Computer. The floppy disk system used 5 1/4" diskettes and could run operating systems like Flex, Star DOS and OS/9 Level 1. I don't recall if OS/9 Level II was ported to the Color Computer. Yes, it was, but only for the CC3, which had an MMU (don't shoot the messenger, that's what Radio Shack called it) and 128kB of DRAM, with an option to expand to 512kB. The source has been open sourced and extended as "NitrOS9", and there's a current "Ease of Use" edition that can be loaded from a CoCoSDC and also has 6309 extensions for faster operation. I believe there was even some kind of hard disk drive interface available, though not from Tandy IIRC. GlensideIDE, sold in the day by the still active Glenside Color Computer Club (GCCC) in Chicago, IL. Also, Cloud9's SuperIDE was also sold. There was a "Burke and Burke" HDD interface that consisted of an adapter, an ISA MFM card (as I recall), and an MFM drive Please just google Tandy Color Computer. Yep. THere's a half dozen FB group, a Discord Channel, and a mailing list. Jim
[cctalk] Re: any COCO enthusiasts
On 1/23/2023 11:22 AM, Chris via cctalk wrote: I don't even remember signing up for the RetroAbout64K mailing list. I haven't seen any actual dicussion in my remembrance. But I do get once or twice a week an email about COCO Nation or some such. Sounds like a hot chocolate enthusiasts group seeking world domination. Anyway I've had COCOs going back. Or 1 that I scarfed from a friend for 20$ (back in 89 I think). I realize it has a 6809 and all, the successor to the venerable 6800. But what can you do with the things? Is there even a color output, despite the name. I can't remember. I only remember playing Dungeons of Daggorath or whatever. The guy I bought it from claimed he programmed a complex naval similation. Yeah whatever. The CoCo uses the 6847, so color is available. (CoCo3 uses an AsIC that supports much of the 6847 capabilities, but adds in more resolution, RGB output, and more colors in those resolutions). The 6809 runs OS9, so there's that. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Computer of Thesus (was: Re: Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man)
On 1/23/2023 10:17 AM, Chris Zach via cctalk wrote: It's the classic "ship of Thesus" argument. And a 2,000 year old debate is not going to be solved on this list. Though the comments started with an absolute (replacing all drives with Goteks), I assume many of us take a more pragmatic approach. As such, I do take a bit of issue with the "where do you stop" concern raised by another poster. I have all 3 here. * I have emulators for many of the machines I own, because often, answering a question can be best/fastest done that way * I have "need to get things done on this" machines, where problematic components are replaced by contemporary equivalents. I know I'm a "young un" on this list of Mini computer owners, but al most all of my daily driver home computers have their floppy drives replaced by SD card or USB equivalents. Because, when I want to enjoy firing up an app or game, I want to enjoy the game/app, not spend an hour/day/week diagnosing and fixing the system. I also use these to demonstrate the units for interested visitors, and these are the machines I take to show to demo and such * I have all stock machines, because, sometimes, only the original will do. Validating specific behavior for emulator writers, checking failure modes on certain apps, understanding actual latency/delays associated with original equipment, etc. These units are used for even the mundane efforts of determining PCB sizes or heights for folks who wish to build add-ons and such. I can't imagine I am the only one of the list with this setup (though I do understand having a daily driver PDP 11 and an all stock PDP 11 might be un-realistic, and so that owner has to make the decision on how to keep the machine configured.) But, for all the smaller units, I must be in a larger community who does this. So, while I don't have the same goal as the OP in replacing all drives with Goteks, I honestly do have that configured already for all my daily/weekly use machines. I lost no existential sleep over doing that. In the spirit of the original thought, though, where I find myself scratching my head are the folks who have replaced every IC on their vintage system with an aftermarket FPGA "equivalent" (loosely used here). The resulting board, with all of the expensive FPGA devices, costs much more than obtaining a second stock unit, and when every IC has been replaced with FPGA, I am not sure I see the value over just obtaining an FPGA-based design where all of the IC functionality has been aggregated into 1 larger HDL-based device. The "keyhole" nature of replacing each individual IC seems expensive, prone to issues, and still relies on constraints of the original motherboard and/or mobo design. But, I smile and nod when I see them at shows, since it must make sense to the owner, and that's how they enjoy the hobby. Jim
[cctalk] Re: Rejected messages
On 1/22/2023 4:52 PM, Adrian Stoness via cctalk wrote: We hear u loud and clear On Sun., Jan. 22, 2023, 4:50 p.m. Ali via cctalk, wrote: Since the switchover I am getting more and more of my messages rejected as suspected SPAM. Anyone else seeing this? bill Same here bill. I contacted the new list owner and the response was pretty much tough cookies -Ali p.s. It would be interesting to see if this one makes it through! LOL. I'm glad I'm not the only one having rejections. I noticed a resend tends to get it onto the list, which seems like a bogus filter (He's a spammer, DENY!... Um, he sent it again, I guess not, let it through...:-) Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: USB Attached 5.25" drives?
On 1/21/2023 6:45 AM, emanuel stiebler via cctalk wrote: On 2023-01-20 18:14, Fred Cisin via cctalk wrote: On Fri, 20 Jan 2023, Chuck Guzis via cctalk wrote: There is also the SMSC USB97CFDC2 floppy usb controller. Al has the datasheet archived on bitsavers: http://www.bitsavers.org/components/standardMicrosystems/_dataSheets/USB97CFDC2-01.pdf also, I found it here; https://www.mouser.com/datasheet/2/374/97cfdc2_01-198397.pdf What more could you ask for--legacy floppy interface, external flash programming... I'm a bit surprised that nobody's come up with a design using this creature. Of course, there's the possibility that they're unobtainium... The older(?) USB97CFDC is still available ... BAH! I just ordered the DC2 part! :-) Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man
On 1/21/2023 2:03 PM, Chris via cctalk wrote: Jim I know all that. Bill found something unclear, it seemed to me anyway. Bill was responding to this comment you made: On 1/21/23 11:41, Chris via cctalk wrote: So converting a 1.44MB gotek to 720kb isn't possible? Seeing you habe to replace the or some part of the stock firmware to use one with difderemt computers would suggest it is a possibility. My question was why a 1.44MB Gotek could't be made ro behave like a 720kb Gotek. My response is that it can indeed. With FlashFLoppy firmware (maybe even with the stock firmware, not sure), Gotek will indeed replace a 720kB drive or a 1.44MB drive. It depends solely on the disk image you select for the firmware to use. If it's a 720kB image, FF/Gotek will look like a 720kB drive to the host, a 1.44MB image will make the FF/Gotek look like a 1.44MB drive to the host. I didn't know others made Gotek clones. Whenever someone wanted to use a Gotek with something other then a PC, something had to be written to the firmware. Or the firmware needed to be replaced altogether. But other then for the reason as someone ponted out each Gotek/clone of different capacity uses a differt uP - why could't the entirety of the firmware be replaced, to make one act as another. But apparently there's more to it then that. There's no more to it. You buy the Gotek or the clone, and you (in my opinion) replace the firmware with FlashFloppy. Load the USB drive up with images of your choice, and select one while the unit is running. The differences in uP is a cost managed thing. The original Goteks and clones used a specific STM part, but the Pandemic caused a parts shortage and so the price for that part went up. Gotek responded by cost reducing the hardware, and so Keir and others responded by reworking the firmware to handle the new part. Once that happened, lots of clones with various ARM-based parts were made, and FLashFLoppy was updated to support many of them (maybe not all of them, so it's important to check the actual uC on the hardware before buying, to make sure FlashFloppy will install. I *think* the standard Gotek or clone firmware can handle a few formats, so maybe nothing needs to be updated/replaced, but I would recommend moving to FLashFloppy anyway, as it's under serious development and bug fixes are handles very quickly. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man
On 1/21/2023 1:36 PM, Chris via cctalk wrote: The 720kbs are ~60% more money. You have to have one of those for an Atari ST, Amiga, etc. I hate overpaying. I'm quite the tight wad. I feel like you may be confusing the two threads here. FLashFLoppy works with Gotek hardware and requires no actual drive, as it replaces the floppy drive. Most people run the FlashFloppy firmware on the unit. FF can support 720kB disk images GreaseWeazle requires a floppy drive, as it plays the part of the floppy controller. I don't use a 3.5" drive/GW combination, since all of the disks I would ever need to archive are 5.25", but I *think* you cna safely write 720kB disks in a 1.44MB drive using GW. IN that case, using a 1.44MB drive should work fine, but I'll defer to others who have used that combo. That said, I believe there were issues in the day in using a 1.2MB 5.25" drive to write 360kB disks, due to drive head size and power output and such. So, the conventional wisdom was to not try to write 360kB disks in a 1.2MB drive. Assuming that was not a tall tale, the same issue would occur with GW, as it's still bound by the specific characteristics of the drive head in use. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man
On 1/21/2023 12:33 PM, Chris via cctalk wrote: Sorry, I don't understand this comment at all. bill C: Jim Brain's comment or my question about converting a 1.44MB Gotek to 720kb? I apologize, as I didn't mean to say any such thing, and I'm looking through the thread to see where I might have implied it. For future reference, if you could privately share, that would be great. Always looking to better my communications. But, to answer, at least with FLashFLoppy, both 720kB and 1.44MB are supported. I don't know about 720kB support with the std Gotek firmware or HxC... Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: USB Attached 5.25" drives?
On 1/20/2023 10:32 PM, Chuck Guzis via cctalk wrote: On 1/20/23 16:25, Jim Brain via cctalk wrote: I'm game to try. I see them nominally listed for sale, so I asked for a quote for 10. We'll see if they are really available or not. I've also seen them being offered on AliExpress... I ordered 10 from there (utsource has been misleading on their parts qtys lately). We'll see if they show up and work. I probably will need help with a design, if anyone's interested in assisting. --CHuck -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man
On 1/20/2023 12:31 AM, Tony Jones via cctalk wrote: On Thu, Jan 19, 2023, 10:18 PM Jim Brain via cctalk wrote: cheaper than KryoFLux (I believe it was designed as a rebuttal for the high priced and "walled garden" nature of KryoFlux) or other related projects like DiscFerret and/or discontinued solutions like CatWeazel (which was a plug in card and harder to support on newer machines) I figured it just was a logical continuation Keir Fraser also wrote FlashFloppy (the alternative firmware for the Gotek) and the associated Disk Utilities software which also is now used in GW. Obviously FOSS is his focus (Xen etc). I'm trying now to forget how much I spent on my Kryoflux :-) As someone who writes FLOSS, it's rarely just to redo something already done well. It's either that bugs or missing features in the original solution annoy me, the cost is too high for the use case, or the designers of the closed source item lord it over the consumers. I don't remember all the details, but I seem to remember all 3 of those were in play when GW came out. Regardless, Keir is an impressive person for making the various projects (FLashFloppy and GW). I think nowadays, everyone immediately replaces Gotek std firmware with FF on the devices as soon as they hit the mailbox. -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: USB Attached 5.25" drives?
On 1/20/2023 5:04 PM, Chuck Guzis via cctalk wrote: On 1/20/23 14:31, Fred Cisin via cctalk wrote: On Fri, 20 Jan 2023, Liam Proven via cctalk wrote: An alternative method is described here: https://blog.adafruit.com/2021/12/08/how-to-build-a-working-external-5-25-usb-floppy-drive-vintagecomputing-ibmpc/ There is also the SMSC USB97CFDC2 floppy usb controller. Al has the datasheet archived on bitsavers: http://www.bitsavers.org/components/standardMicrosystems/_dataSheets/USB97CFDC2-01.pdf What more could you ask for--legacy floppy interface, external flash programming... I'm a bit surprised that nobody's come up with a design using this creature. Of course, there's the possibility that they're unobtainium... --Chuck I'm game to try. I see them nominally listed for sale, so I asked for a quote for 10. We'll see if they are really available or not. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man
On 1/20/2023 2:33 PM, Chris via cctalk wrote: At least 1 person is interested in a Canon AS-100 boot disk. I know my day will come. Remember they came with an error or some weirdness from Canon. You couldn't use normal disks with it. They had to be supplied by Canon, whether 5 1/4" or 8". Likewise, Tandy Model 100 TPDD system disks are hard to make if you don't already have a working TPDD system disk and can just make a copy of it. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: [SPAM] Re: USB Attached 5.25" drives?
On 1/20/2023 2:31 PM, Zane Healy wrote: Realistically that’s good enough Jim, though I find the way the 3.5” floppies are working to be quite useful. I can take a look at what’s on them, and in many cases, I just pull the files off. As there is no reason to image them. No doubt. Don't get me wrong, GW and KryoFlux and Catweazel(sp?) and others serve a great purpose. But, most media is not so important. I have some geneology disks a family member worked on in the 1980s that I need to archive. But, it does not rise to the need to flux image. I'll just pop them into a DOS PC and grab the data. If there are issues, we'll cross that bridge then. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: USB Attached 5.25" drives?
On 1/20/2023 1:05 PM, Mike Katz via cctalk wrote: Using the Greaseweazel is a two stage process. The GW itself connects to the actual drive and just records the flux transitions as a series of zeros and ones. This is transferred to a computer (PC, MAC, Linux) where the captured flux image is analyzed by a second program which understands floppy formats. You tell the analyzer what you are looking at. The analyzer can then provide a binary dump of the actual data (track by track) or for operating systems that it understands it can extract directories and files. On 1/20/2023 12:52 PM, Zane Healy via cctalk wrote: I’m now aware of the GreaseWeazle, but what I’ve not seen is if it allows standard access to the data on a floppy, or only provides a way to image the disk. With an USB attached 3.5” floppy the disk mounts on my Mac, and I can easily pull files off the disk. Does this work with the GreaseWeazle and a 5.25” floppy drive? Zane Not to discount Mike's response, but to Zane's original question: At this time, No, the GW only allows imaging. *BUT*, there is nothing preventing the firmware Keir wrote from being extended to support accessing the actual floppy disk directly via the USB interface (by emulating a regular USB floppy drive set of commands). In reality, most people just do with Mike is suggesting. Grab the image and then mount it as a virtual floppy and read the files/dirs as needed. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man
On 1/20/2023 3:53 AM, Christian Corti via cctalk wrote: On Thu, 19 Jan 2023, Fred Cisin wrote: I would recommend 5170 (AT), to also have the 500K bps data transfer rate of its FDC. I just had a good laugh ;-) Newer PCs often have unnecessary complications. Many no longer even support floppies! Since when does the Weazle need a floppy controller? It's an autonomous device. And you *do* need a modern PC since it is attached via USB. Christian You'll see below the response you quoted, the original responder meant to say ImageDisk, not GW. -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man
On 1/19/2023 11:55 PM, Bill Degnan via cctalk wrote: My catweasel 4, which I assume is more or less the same thing works fine in a p3 pentium system. Is the hreaseweazle totally different? It is. It's a small STM32-based uC that supports USB, and so can be loaded with firmware to look like a USB device on a PC USB chain. The GPIO of the uC then connects directly to the FD and tickles the signals and reads the raw data, sending it onto the PC via USB. Tony provided the links in the response you quoted. You can buy premade GW PCBs, but the original design was just a small STM32 "Blue Pill" dev board and an FD. The BluePill was like $10 or so, making this much cheaper than KryoFLux (I believe it was designed as a rebuttal for the high priced and "walled garden" nature of KryoFlux) or other related projects like DiscFerret and/or discontinued solutions like CatWeazel (which was a plug in card and harder to support on newer machines) Jim
[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man
On 1/19/2023 9:28 PM, Fred Cisin via cctalk wrote: On Fri, 20 Jan 2023, Chris via cctalk wrote: So the ideal setup for best utilizing a GW is what? Or does it not matter if it's a 5150 or a Pentium4? I would recommend 5170 (AT), to also have the 500K bps data transfer rate of its FDC. Newer PCs often have unnecessary complications. Many no longer even support floppies! Maybe 5170 means something different to everyone else here than it does to me (I thought it meant IBM PC AT), but GW requires a machine capable of USB, and I think the system needs to run either a recent version of Windows or Linux OS, or be a recent vintage MacOS (maybe a FrankenMac would work, but still, something that will run a recent MacOS version) Maybe the question is about ImageDisk, which the 5170 would be fine for (I have a PII sitting here that runs it with a 1.2MB/1.44MB switchable dual disk in a half height bay, and a 360kB head load Tec that I think I bought from Chuck or at least someone on here (still working awesome, BTW. OS is DOS 6.XX (whatever the newest was before v7 dual boot with Ubuntu) Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man
On 1/19/2023 8:23 PM, Chris via cctalk wrote: I have to be honest at this point. A disk srive in some sense "responds" in some sense to changes in flux density around the surface of disks. So what is the GW picking up, other then what the drive is already reading? It's an interim device that sits between the drive amd the cable. It makes use of signals that travel between the drive and fdc. Does it read a disk better then say Diskimage can? I think folks are being too MFM-centric in their responses to this question. "ImageDisk can identify, read and write any disk format that a PC floppy controller can handle — so *it can do most FM/MFM formats*, but not Amiga disks with odd timing, or Commodore 8-bit disks with GCR encoding. " GW can do the same, but can also handle GCR encoded disks, the Amiga disks noted above, and it might be able to do older Apple Mac 720K disks It's really not fair to compare ImageDisk to GW. ImageDisk is limited to the configuration options and assumptions built into the FDC. GW has no such restriction. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man
On 1/19/2023 3:38 PM, Paul Koning via cctalk wrote: On Jan 19, 2023, at 4:31 PM, rar--- via cctalk wrote: Museum Staff Helps Exonerate David Veney January 19, 2023, Hunt Valley, MD — Staff members of the System Source Computer Museum recently completed a project that helped exonerate David Veney, wrongly convicted of rape in 1997. In 2005, after Mr. Veney sought a new trial, the state found irregularities in the prosecution, released Mr. Veney from prison, and declined to re-prosecute. ... Wow. That is a marvelous story. Just one comment: using the GreaseWeazle makes sense here, but other options would include seeking out the help of the community. For example, 5.25 inch floppy drives are widely available, and reading RX50 format on an ordinary drive in Linux is a trivial exercise. Similarly, feeding the recovered device image to a SIMH instance would be easy enough. The tricky task of translating the application data to readable text still remains in any of those approaches, of course. paul I see it as seeking out the community. Your point probably is about casting a wider net to individuals, but I think asking an organization to help creates more comfort, especially if you're talking about irreplaceable data like this. Given the age of the disk and the expectation for errors, even if a single community member had been asked, I doubt they would try to read it from Linux or similar. It's an option, yes, but not a recommended one, since you might have limited reads available, and a flux read gives you maximum data with minimum effort. Your SIMH thought makes a ton of sense. Not knowing the effort here, I would assume once the flux image was available and with the lack of SW to do much with the data available anyway, treating it like a raw data dump was probably the most expedient option to get to the end goal. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: PT-68K
On 12/27/2022 9:52 PM, Bill Degnan via cctalk wrote: Which issue of Radio Electronics? "Build the PT-68K" Oct 1987 and Nov 1987 and Dec 1987 and Jan 1988 and Feb 1988 and Apr 1988 and May 1988 and Jun 1988 and Jul 1988 and Aug 1988 and Sept 1988 and Dec 1988 and Jan 1989
[cctalk] Re: PT-68K
On 12/27/2022 8:47 PM, Chris via cctalk wrote: It's a IBM PC form factor 68000 based project that was featured in Radio Electronics. Anyone remember it or even know what I'm talking about? It would be a fun prokect. I remember it, and I believe I have all those issues, as a project to complete at some point. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: [SPAM] Re: what is on topic?
On 12/22/2022 5:02 PM, Fred Cisin via cctalk wrote: Another possible exception for banning XP: I think that the OQO is interesting enough to call for inclusion. It is a handheld, running XP. Screen slides partway off to reveal a keyboard. /me looks at his OQO 2, which still works (and has XP on it, as I recall). Battery is no more, though. it has the docking station as well. Bought new in 2005 or something.
[cctalk] Re: Replacing NiCd with NiMH in a pro way.
On 12/22/2022 4:08 AM, Cedric Amand via cctalk wrote: Hey everyone, No - I won't ask if this is on topic or not :) I'm currently reparing an ALPS plotter ( a Tandy "ce 150" equivalent ) and it's not the first time I face the same problem ; how to replace NiCD batteries. In the past what I did is actually order new NiCd ( you can still find them here in Europe, well actually out of europe but in eastern countries close to europe ) However they are at best NOS nowadays, that does "work" enough for moderate use (I've done that on vintage laptops) This time I'd like to go a bit beyond that and replace the NiCd with modern NiMH (the plotter coils and motors will benefit the extra power) However the trickle chagre of NiCd applied to NiMH will either kill my batteries or kill me in a house fire. I see small $1 NiMH 5S charging boards on Aliexpress, I thought I might use that, try to shove it it the CE150 (or other devcies with the same problem) TL-DR : Before I re invent the wheel here ; Has anyone developed a proper way to replace NiCd with N iMH in vintage (mostly portable) equipment ? And I mean not simply swapping the batteries, I don't want that, I want a proper charge process. I apologize that I don't have an answer to the main question on how to upgrade from NiCD to NiMH, as I considered it for a similar portable printer a few years back, but decided I was not willing to incur the risk for the usage I envisioned. My comment has more to do with the statements about NiCD batteries you made. Is there a size constraint that hinders finding new cells to use? I find brand new NiCD batteries of quite a few sizes all over, as many folks use them to re-pack portable tool batteries and other similar uses. I've repacked quite a few NICD containing systems (Old HP portable computer, camcorder, printers) with these new NiCDs, which all are smaller, have more storage capacity, and are brand new. If you decide to continue with NiCD and send cell dimensions, I'm happy to see what I can find that's new. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: what is on topic?
On 12/21/2022 1:22 AM, Chris via cctalk wrote: Ok for cbm and atari yes I'm familiar with most of those. I meant in general. And specifically where would you go for server related discussions for pII through socket 771? I admit Pentium and newer forums are a bit harder to find, but some stuff is at: https://forums.tomshardware.com/ https://forum.vcfed.org/index.php?forums/pentium-2nd-and-3rd-generation-class-machines.1230007/ https://forums.anandtech.com/categories/hardware-and-technology.27/ The first two are probably closer to what you're looking for, though I don't see server-specific groups. Jim
[cctalk] Re: what is on topic?
On 12/21/2022 12:28 AM, Chris via cctalk wrote: I keep hearing allusions to many forums. I think there are very few. I don't do FB. There are many web forums. Just for CBM, there's lemon 64, vcforum, atariage (yes, CBM on atariage), denial, Everything 64, and 6502.org handles a few things. If you can grok German, there's forum64.de Mailing lists include cbm-hackers. Apple, TI, Atari all have similar. AtariAge handles all of them nominally. Retro Hackers also handles multiple. Jim
[cctalk] Re: what is on topic?
On 12/21/2022 12:03 AM, Chris via cctalk wrote: Apples and Coco's and C64's would be the common sublist As much as I enjoy these machines, I ask that we do not create yet another list for them. There are many fine forums for all of these machines. The occasional PET or VIC question in here surely won't ruffle too many feathers, and those of us who know quite a bit about these machines can redirect the OP elsewhere if needed.
[cctalk] Re: what is on topic?
Well, that's one nay for this topic. :-) Jim
[cctalk] Re: reset "pulse" stretcher need
On 12/7/2022 12:06 PM, Sellam Abraham via cctalk wrote: Just glue the contactor thingy back onto the motor spindle. Done. Not done, as that's not the concern I am trying to address. I realize my posting is not fully on topic, but if you are annoyed, just don't respond and delete. Jim
[cctalk] Re: reset "pulse" stretcher need
On 12/7/2022 11:28 AM, Mike Stein via cctalk wrote: I don't suppose there's an extra NC contact on the motor switch/relay? If so, a relay would do, otherwise two relays. Sadly, no relay at all. Since I was afraid of being off topic on the list, I hesitated to annoy folks with too much detail, but it's unfair to those helping, so my apologies. The device in question is a 1960's era NuTone 8 note door chime (doorbell). I don't know the exact model, but here are some links to similar units: https://www.youtube.com/watch?v=kbOVmMVrSTg http://northsideforyourhome.squarespace.com/nutone-vintage-door-chime/nutone-lb42-westminster-8-note-chime/ I admit I grew up in a later period and I have lived under a rock for part of my life, so I did not know such cool devices were once sold. If you can excuse the terrible narration, I put a small video together to go over the unit, since I'd never seen such a cool piece of kit before (living under the rock, so to speak). https://youtu.be/HhGMhiAjmRU The motor in question is a 3.6RPM "clock" motor, as far as I can tell. It runs the "program", and the front doorbell switch engages the motor momentarily to start the process. I came upon this slice of home ownership by way of my sister and brother in law, who hosted thanksgiving at their "new to them" home, which looks to have not been renovated since it was built in the early 1970's. This chime, in addition to an 8 room NuTone intercom system, are installed in the home to this day. All of us think the system is impressive and must be kept in the home. It actually took us a while to find this, as I offhandedly commented we had to knock on the door since the lighted doorbell didn't seem to do anything, which prompted BIL to note they had lived there for a month and had yet to find the door bell in the home (the lighted front button heavily suggested in operating unit somewhere). We finally found it in the entryway, disguised as a part of the Intercom system (made by the same company). We were unsuccessful in diagnosing the issue in the moment, but I was able to take the unit home to work on it. As the video notes, I was able to determine and address the immediate issue, but I notice the timing issue I wanted to solve it before returning the unit. The video was mainly to explain to my sister and BIL what had been wrong with the unit. Given the nature of the unit, the switch has to remain a NO SPST, and I'd really prefer to not rewire the switch and disconnect it from the 24VAC, since some buttons assume they are being driven with 24VAC. I also prefer not to make any non removable changes to the unit. I figured adding something to the terminals is easily removeable and thus fair game. It works as-is, but I can see people tapping the button too fast and then my BIL deciding to replace the unit after annoying friends or missing packages. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: reset "pulse" stretcher need
On 12/7/2022 8:43 AM, Patrick Finnegan wrote: My two thoughts would be: 1) A 555-timer in one-shot mode That was my thought as well. 2) An S-R latch at is set by the push button, and cleared by 2nd switch Due to the vintage nature of the device, separating the switches and wiring them this way would require doing some invasive modification of the unit, and it's not mine to modify. Though, I agree with other comments, this S-R latch idea is a cool one. Pat -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] reset "pulse" stretcher need
This might be a bit off topic, so forgive me if so. The issue is a 24VAC motor with one connection to 24VAC and the other gated via two switches. The first switch is a momentary one and the second is in parallel and connected to the motor. A long enough momentary depression on the first switch actuates the electric motor enough to close the second switch, which then stays closed for 1 revolution. The problem is that a quick enough press and release of the first switch does not allow the motor to move far enough to close the second switch. Given the configuration, my general plan was a small one shot timer circuit that energized when the switch was initially depressed and then closed a relay in parallel with the first 2 switches, with a time period that was 1/10 to 1/2 the time of the motor revolution. a quick close and release of the first switch would start the timer, which would then close the parallel switch and then open it a short time later, and then the motor switch, which would still be closed, could signal the end of the cycle. But, I thought I'd ask around and see if a simpler option was available. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
[cctalk] Re: Bubble Memory
On 10/21/2022 9:46 PM, Tom Hunter via cctalk wrote: It would be better to stay on topic and avoid the hostile rhetoric of some of the posts. Um, I am. There were concerns about international shipping of this eBay item, followed by some info on eBay international shipping, so I was offering to help in general if folks need it, and noting that not everyone requires so much to ship. Jim
[cctalk] Re: Bubble Memory
On 10/21/2022 4:55 AM, Peter Corlett via cctalk wrote: On Fri, Oct 21, 2022 at 12:15:02PM +1100, Doug Jackson via cctalk wrote: [...] Yet another American seler who doesn't understand how simple overseas shipping is. As far as I can tell, the price to ship anything overseas from the USA is twice the value of the item, plus fifty bucks, plus ten bucks per ounce. Whether USPS actually charge this much or it's just sellers trying it on, I neither know nor care. So I don't bother even looking at American sellers any more. I ship all the time all over the world, and overseas shipping is a bit pricey, but I don't think it's quite that bad. I think that's an eBay thing. I don't use PirateShip (though I am sure they are fine), as I have a business shipping manager I use, that gets me preferred rates like PirateShip. If you find something you'd like but the seller doesn't do international, feel free to reach out. I'm not looking to make a business of reshipping, but I started this business to help folks enjoy their classic computing hobby, so I'm happy to help. As another posting noted, though, requests to modify customs forms is a problem. The most vocal concerns I've heard are folks who buy outside the US, have t pay customs, and then complain to me that I should have shown the price of the item including customs and VAT and such costs. I agree it'd be nice, but it's untenable at times to pre-figure those fees. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
Bob Lucky
I don't remember seeing this here, and not sure how many of you read his articles, but: https://spectrum.ieee.org/bob-lucky-obituary -- Jim Brain br...@jbrain.com www.jbrain.com
Re: Found my favorite DOS editor
On 9/28/2021 4:44 PM, Cameron Kaiser via cctalk wrote: 'course, then there are the MAJOR religious battles. Such as VI VS EMACS. "I've been using vi for about two years, mostly because I can't figure out how to exit it." (written in vi) I try to stay out of the VI/Emacs war, but I do use VI on all my devices. I had a portable DOS, OS/2, Win16 console, Win32Console, Linux set of floppies I could easily pop in to have VI on any machine I needed to work on/with. It was less of affinity for the specific editor as it was just a need for some consistency so I could focus attention on other things. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
Rockwell 65001EAB3
I know it's a long shot, but wondering if anyone might have a Rockwell 65001 EAB3 type IC lying around in a discard pile or otherwise willing to go to a new home. Here's a pic of one in the Commodore C900 keyboard: https://i.ibb.co/tZ2m68x/IMG-1538.jpg I see one online for sale, but the both the pricing is untenable for a device I don't need to use but just wanted to research and I also don't want to prohibit a known good device from being available if needed. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
Re: IBM PC Network
On 5/23/2021 4:49 AM, dave.g4...@gmail.com wrote: I don't believe that any of the early LAN products emulated what IBMers would call an FEP. Generally, an FEP is a 37XX computer running NCP, EP or PEP. I'll easily concede, as a) all of the IBM terminology seemed alien to me when I joined the company and I was just trying to tread water coming from the micro/pc/unix world, and b) what good memory I did have on all of the IBM networking got pushed to the side as new positions and companies came and went and I didn't use that knowledge. The early tools generally appeared to the Mainframe as a 3174 Terminal Cluster Controller and attached screen. They did not emulate any of the 37xx or 3174 CPUs, they "just" re-implemented the IBM protocols. That sounds right. The tools were not limited to terminal emulation, they would also allow PC applications to connect to the Mainframe using a range of SNA protocols. SNA, there's a term I had completely forgotten about. I will admit, though, the IBM network protocol documentation (I want to say they were called Red Books, though they were not red) set a high bar for API and protocol documentation that I have rarely seen elsewhere in my travels. I do miss that. I would say they are all old enough and obsolete enough to be considered "in scope" on here. Dave -- Jim Brain br...@jbrain.com www.jbrain.com
Re: IBM PC Network
On 5/23/2021 2:02 AM, Jim Brain via cctalk wrote: I, of course, came from UNIX and TCP/IP land, and 802.2 and all these crazy protocols were just bizarre to me. I had bought the Comer books right after college because I was trying to implement TCP/IP on my Commodore 64 (got SLIP, TCP, and IP working, back in 1995 or so), and there was a guy at the company named Walter Falby who was a uber 370 programmer. At one point, he was leading the Compuware group writing a program that would trick the 370 into feeding different dates to regular apps on the machine, to be sold as a utility to help companies test their SW for the year 2000 rollover. Deep knowledge of 370 assembler. Reminds me of "Mel" of the free verse story fame. Anyway, Falby started asking me about TCP/IP, and I was happy to share what I knew. He borrowed my Comer books and printouts of the RFCs (not sure where I printed them from back in those days, but they were available somewhere) and implemented a full TCP/IP stack for the 370, they called it Host Communications Interface (HCI). I'm not sure if Compuware gave HCI away to customers or they just charged a bit for it, but I remember Walter being stupified IBM was selling TCP/IP for such a high price and deigned to do something about it. Dang, knew I should have checked my memory before I posted. Walter Falby is a great developer as well (still works at BMC/Compuware), but the HCI guy's name was Andy Coburn, and he is sadly passed on. A great 370 developer.
Re: IBM PC Network
On 5/23/2021 12:31 AM, Grant Taylor via cctalk wrote: On 5/22/21 7:12 PM, Jim Brain via cctalk wrote: I guess that's a selling point of TR, but I loathed it when introduced to it after using Ethernet at UIUC. Having to learn CPI-C, LU-2, LU-6.2, APPC, etc. and configure Communications Manager/2 on OS/2 to emulate a FEP (3174?, not sure, my mind tended to bury such information, and in fact I'm not sure if that's what it did or if it connected to a FEP, that info is gone and I've no desire to go review it). Given the things that I play with, I'd like to know more. But I suspect that this isn't the forum. Oh, I don't know, I mean, CM ES and CM/2 were just OS/2 emulators of a FEP, I believe (they were emulating something, I know that much), and we talk about other emulators on here all the time. It was 1993, I was fresh out of college with a Computer Engineering (kinda like a EE degree, but with small signal instead of power design in the last semesters) degree from UIUC and the job market seemed in the dumps. Hardware jobs (I interviewed at Motorola to work on the uC group, but no dice) were scarce, and software development openings (CompE had some CS classes in it) were bad as well, but a bit better. Took a job with Compuware (still in business, I believe... Yep, now part of BMC), one of the IBM barnacle companies, to coin a term (they wrote some industry standard apps like FileAid and AbendAid and XPediter, if my memory doesn't fail me) for IBM shops. IBM-like dress code (dress slacks, shoes, college shirt, tie), but it paid well. I was hired in their communications group, working on a multi-platform piece of code called "GCS" (Generalized Communications System). The overall idea was to create OS/2 counterparts for the company's mainframe flagship products, some of which could also function as front ends for the mainframe versions. File-Aid, for example, was a file transfer/file manipulation app on the mainframe, and FileAid/2 did the same on OS/2, but also allowed transfers to/from the mainframe. The transfer functionality required a way to do transfers, as one can expect, and the goal was to support as many customer configurations as possible. GCS was born. GCS was a set of libraries that provided some low level transfer routines that could be compiled into mainframe and OS/2 apps (RS6000 as well, and later Windows 3.1 and Windows NT). The transfer was protocol agnostic, but there was a directory server functionality that would configure which protocols could be used between two endpoints. Sometimes it was CPI/C, which I think was a half duplex true communications protocol, while others were APPC/LU6.2, as I recall (I didn't do much with the actual protocols, as I was junior on the team), which could be full duplex. The bare minimum was LU2, which I believe is 3270 protocol. It's probably old news to anyone on here, but LU2/3270 was a horrible way to transfer files. Essentially, you would connect to the 370, it would pass control to the endpoint, you would send a screen of data back, it would send data back to you, repeat. To do a file transfer using LU2, you would use the OS/2 communications low level libraries to create a virtual 3270 screen and connect to the mainframe (using connections strings retrieved from this directory server thing our team had written) and send some EBCDIC chars in the first field, the 370 would then respond to those, etc. If a file needed to be transferred from mainframe to PC, the PC sent the required set of "commands", and the mainframe split the file into 80x24 chunks of data and sent it down, the client re-assembling and passing off the resulting blob. Smarter people in the group than I realized the 370 terminal environment would support 3270 terminals that were up to 16384 or so bytes in size, whatever that translated to in rows and columns. So, all 3270 virtual sessions were created with those dimensions, to save the number of splits and chatter. I configured CM/ES and CM/2 to hook the GCS endpoints to the mainframe and populated the paths in the Directory Server to denote which protocols were used for which paths. I realize now that outside of groups like this, no one understands half duplex transmissions. GCS simulated full duplex conversations over half duplex pipes, which required an insane amount of work, but we created tons of little threads in OS/2 to manage all of the housekeeping. The idea was that the developer and end user need not care if LU6.2 (full duplex) or LU2 or CPIC (half duplex) was in use. I'm laughing now thinking of all of the web and even TCP/IP devs who take full duplex for granted and don't even know about half duplex. Anyway, the system seemed (in retrospect) as brittle as it sounds. I went on a number of beta installs to IBM shops to install and configure, and it was a chore each time. Navigating not only the TR segments, v
Re: IBM PC Network
On 5/22/2021 7:50 PM, Lyle Bickley via cctalk wrote: BTW: 16 Mbit Token Ring was much more reliable (especially in "noisy" environments) and considerably faster with more consistent performance than 10 Mbit Ethernet. We won a number of large contracts when other network companies used twisted pair 10 Mbit Ethernet in "noisy" environments and their networks failed miserably. I guess that's a selling point of TR, but I loathed it when introduced to it after using Ethernet at UIUC. Having to learn CPI-C, LU-2, LU-6.2, APPC, etc. and configure Communications Manager/2 on OS/2 to emulate a FEP (3174?, not sure, my mind tended to bury such information, and in fact I'm not sure if that's what it did or if it connected to a FEP, that info is gone and I've no desire to go review it). When the network worked, it was fine, of course, but it seemed every week someone would do something that would switch a TR card in a PC to 4Mb, and the entire network would die, "beaconing" for an hour while the IT folks ran around trying to figure out where the issue lie. And, it was an office building, so not a ton of noise... Seeing the 370 (3090, as I recall, nice imposing looking machine) was impressive, and I will admit working in a firm with an IBM 370 architecture machine gave me a new and profound appreciation for the staying power of the mainframe (I started the job thinking, as all recently minted IT professionals no doubt think, that the mainframe was soon to be discarded in favor of UNIX and potentially the newly arrived Linux OS. That job changed my mind). But, I never grew fond of TR, and as soon as IBM supported Ethernet, I was happy. (Plus, there was no TR driver in Linux initially, and we all desperately wanted to run Linux on our PCs to run a real OS instead of Win3.1 or OS/2. OS/2 was nice, to be fair, but it was not UNIX...) Jim
Searching for Elevated socket
IN my continuing Digitalker saga, I did find a couple not horribly priced Digitalker ICs online and purchased them. As one arrived, I found that my original IC was actually OK, but the cable from the computer to the device has issues. I've traced it to what looks like a heavy duty 16 pin IC socket on the board that plugs into the computer, and into which a 16 pin 2x8 .3" DIP IDC header plugs into (with the IDC cable going to another such header, which plugs into a similar socket on the main synthesizer PCB). The socket has the same basic footprint as a normal 2x8 16 pin .3" IC socket, but it's much heavier duty. I could replace with a simple leaf socket, but would prefer to find a direct replacement. Though I am sure other manufacturers sold similar, I find that Aries sells that I need. It's an Aries 16-8430-10 <http://www.beckwithelectronics.com/ARIES/16-8430-10.htm> (or could be an Aries 16-8480-10 <http://www.beckwithelectronics.com/ARIES/16-8480-10.htm>) elevated IC socket. The link below shows the units: http://www.beckwithelectronics.com/ARIES/8xxx.htm Digikey has the 14 pin version in stock, but no 16 pin ones, and neither does Mouser. I'll keep searching, but they are very expensive and I'm not sure I need 40 of them (minimum Digikey order). Thus, I am wondering if someone on list has 1 or 2 they might be interested in selling for the cause. The good news is that I was able to get the connection to work, and now the unit operates as designed. Still, I do not trust the socket. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
Re: Digitalker 54104 IC
On 2/13/2021 3:13 AM, ED SHARPE via cctalk wrote: oddly... I still have the prototype unit we built to plug into HP 2000 series processors and 21mx processors. it sits in my den...I was looking at it the other day! and then your message popped up/ What are looking for I am not sure I got all the prior emails on this Ed# In a message dated 2/12/2021 4:01:25 PM US Mountain Standard Time, cctalk@classiccmp.org writes: On 2/11/2021 6:02 PM, ED SHARPE via cctalk wrote: Most challanging was to figure out to make it say naughty things... and once you did how it almost caused havoc in AZ Sounds like a story to add detail around... But, I'm sad because no one either has one nor can help me test this one. So, I cannot enjoy the thrill of making it say inappropriate stuff :-( Forwarded Message Subject:Digitalker 54104 IC Date: Tue, 9 Feb 2021 22:02:20 -0600 From: Jim Brain To: General Discussion: On-Topic and Off-Topic Posts I suspect the answer to question #1 is no, but thought I would ask. 1) Anyone happen to have a known working Digitalker 54104 IC they are looking to trade for some cash that does not involve me selling an arm or a leg :-)? 2) Barring that, anyone have a known working Digitalker-based unit that might be able to pop in a suspected non working Digitalker IC and test? I have a Jameco (yep, the parts firm) manufactured Digitalker unit here called the JE-520 that is my original unit. It suffered some ROM bit rot long ago and was not working, but I acquired the ROMs a while back to repair the unit. Now, though, as I pull it out for another project, it seems to be misbehaving. It's like "address bit 1" on the input commands is acting up. For instance, word 48 is "zero", and 49 is "one", but zero will be followed by "three" and then "zero" and then "three" as one sends values 48,49,50,51 to the unit. I'm working to confirm the bit 1 on the cable to the PC is not bad, but initial efforts point to it being the IC. Jim -- Jim Brain br...@jbrain.com www.jbrain.com -- Jim Brain br...@jbrain.com www.jbrain.com
Re: Digitalker 54104 IC
On 2/11/2021 6:02 PM, ED SHARPE via cctalk wrote: Most challanging was to figure out to make it say naughty things... and once you did how it almost caused havoc in AZ Sounds like a story to add detail around... But, I'm sad because no one either has one nor can help me test this one. So, I cannot enjoy the thrill of making it say inappropriate stuff :-(
Digitalker 54104 IC
I suspect the answer to question #1 is no, but thought I would ask. 1) Anyone happen to have a known working Digitalker 54104 IC they are looking to trade for some cash that does not involve me selling an arm or a leg :-)? 2) Barring that, anyone have a known working Digitalker-based unit that might be able to pop in a suspected non working Digitalker IC and test? I have a Jameco (yep, the parts firm) manufactured Digitalker unit here called the JE-520 that is my original unit. It suffered some ROM bit rot long ago and was not working, but I acquired the ROMs a while back to repair the unit. Now, though, as I pull it out for another project, it seems to be misbehaving. It's like "address bit 1" on the input commands is acting up. For instance, word 48 is "zero", and 49 is "one", but zero will be followed by "three" and then "zero" and then "three" as one sends values 48,49,50,51 to the unit. I'm working to confirm the bit 1 on the cable to the PC is not bad, but initial efforts point to it being the IC. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
Re: TM848 repair?
On 7/13/2020 6:10 PM, Chuck Guzis via cctalk wrote: Don't mention it--happy to help out! I am especially impressed, for a few reasons. Backstory: * I snagged 2 Model 12s at a CoCoFEST! a number of years ago during the show auction. NO KBs * I then spent too much I am sure buying extra boards from a chap outside Atlanta who seemed to have sold these units for years. * Peter Cetenski was gracious enough to get me a few bootable floppies to try. * Then, when picking up the Atlanta parts in Chicago (they came via someone's back seat, I by plane), Jason Timmons loaded me up with more Model II stuff (external drive, front bezels, and a few Model IIs, including a batch of KBs. * Finally, at Tandy Assembly 2018, I picked up 2 external HDDs for not much coin) * But, I have been sitting on all this collection in unusable form since then. It's taking up valuable space and I know I don't need it all, so I really need to get the units working I want, and then move the rest to a new home. * Still, all of the units collectively seemed a daunting task, especially in light of my not knowing anything about the platform. I don't even know how to list a dir in TS-DOS 2.0a (or whatever it is called). LS-DOS uses dir, so there's that. Of the 4 units, 1 requires a new resistor (well, at least 1 new resistor), 2 were bad caps (now booting), and 1 has a good mech (swapped logic board with another one), but the logic board has another issue. Resistor is good, cap is good, and VR is outputting 11.9VDC. The stepper moves when booted, and the drive motor also looks to be running well. I can see the LED showing the index pulses, but not sure where I should start (I have it sitting in a working mech, so I know all mech is at least marginally OK (was booting from the mech with another logic board). Jim -- Jim Brain br...@jbrain.com www.jbrain.com
Re: TM848 repair?
On 7/13/2020 5:23 PM, Chuck Guzis via cctalk wrote: On 7/13/20 2:05 PM, Jim Brain via cctalk wrote: --Chuck Thanks for the tip. On one, the 10ohm (yep, 10) is cooked, so I need to get another one. Looks like 1/2W, but anyone know for sure? The schematic just notes the resistance and identifier. It could be 1W... Given the power consumption (up to 1.2A) on the 24V line, I'd play it safe and go with 2W. --Chuck I also am at a loss on the 4u7 cap. The one I am replacing is a black unit with a tapered + end, but I am not finding exact duplicate. Will this work: https://www.digikey.com/product-detail/en/nte-electronics-inc/NEH4-7M50AA/2368-NEH4-7M50AA-ND/11644580 -- Jim Brain br...@jbrain.com www.jbrain.com
Re: TM848 repair?
On 7/13/2020 2:11 PM, Chuck Guzis via cctalk wrote: On 7/13/20 12:00 PM, Mike Stein via cctalk wrote: Shouldn't be too difficult to troubleshoot; have you got the manual? Start by checking the 24V > 12V regulator... Second that! I've had to replace more than one regulator on 848s; also the 100 ohm resistor (R1) and electrolytic capacitor(C6) on the input side of the regulator. --Chuck You, my good man, need some funds. I will send funds so you can grab a beer or something! The one unit has a bad resistor (need to order), while the other has a shorted C6 (temp replaced with a radial cap while I order one of those. That one boots now. I was dreading trying to debug these things, and no doubt they won't all be this easy, but some early success foes wonders for confidence to continue. Thanks for the help! Jim -- Jim Brain br...@jbrain.com www.jbrain.com
Re: TM848 repair?
On 7/13/2020 3:57 PM, Mike Stein via cctalk wrote: As for a manual, I have this: https://www.scss.tcd.ie/SCSSTreasuresCatalog/hardware/TCD-SCSS-T.20141115.002/Tandon-TM848-Specification-and-Schematic.pdf I don't see the VR section in that, though. If it's the same document that I have, PDF page 18, second-to-last page of schematics, near the bottom, near the legend "DC POWER CONNECTOR" --Chuck Which document is that? I find it on PDF page 85 of the OEM Operating and Service Manual TM-848-1 and TM-848-2 Disk Drives, Sheet 4 of 5. It's the first one I linked (above). It looks to be an older manual. I agree the one you linked has more information, so I grabbed both. Jim
Re: TM848 repair?
On 7/13/2020 2:11 PM, Chuck Guzis via cctalk wrote: On 7/13/20 12:00 PM, Mike Stein via cctalk wrote: Shouldn't be too difficult to troubleshoot; have you got the manual? Start by checking the 24V > 12V regulator... Second that! I've had to replace more than one regulator on 848s; also the 100 ohm resistor (R1) and electrolytic capacitor(C6) on the input side of the regulator. --Chuck Thanks for the tip. On one, the 10ohm (yep, 10) is cooked, so I need to get another one. Looks like 1/2W, but anyone know for sure? The schematic just notes the resistance and identifier. It could be 1W... The other 1 I have on the bench looks to have a good resistor, but I will check the VR next. Jim -- Jim Brain br...@jbrain.com www.jbrain.com
Re: TM848 repair?
On 7/13/2020 2:29 PM, Chuck Guzis via cctalk wrote: If it's the same document that I have, PDF page 18, second-to-last page of schematics, near the bottom, near the legend "DC POWER CONNECTOR" --Chuck Eyesight is failing. I had the same doc. -- Jim Brain br...@jbrain.com www.jbrain.com
Re: TM848 repair?
On 7/13/2020 2:02 PM, Chuck Guzis via cctalk wrote: On 7/13/20 11:18 AM, Jim Brain via cctalk wrote: The Tandon 848 is not one of my favorite drives. There is an option not to pass the Motor On/ signal unless a disk is loaded and the drive door is closed. Check U16 pin 8, which should be high for MOTOR ON. I will do so. It seems more like an oversight that all 4 drives don't spin. Be aware that the 848's motor controls are different from 5.25", where one line controls all motors. The 848 uses pins 4,6,8 and 24 on the interface to control the motor--each drive has a jumper that dictates which line will be used. (MC 1-4). Yep, one of the drives was set to DS2, so I moved it back to DS1 so I could test as a primary drive. I agree the drives would be different from 5.25" ones, but I connected them to the same PSU that runs my TM848E successfully. It seems strange that a working PSU that drives a TM848E would not supply enough or the right voltage for a TM848-02. Jim
