test-drb October 2005

test-drb@ccmp.vtda.org

264 participants
655 discussions

by tshoppa＠wmata.com

Chuck asked: >> picture: http://toresbe.at.ifi.uio.no/3266.jpeg > What's that big orange unit off to the right? It's upside-down, judging by the couple of characters visible :-). Tim.

19 years, 1 month

Looking for an 8 bit FDC...

by ajp166＠bellatlantic.net

> >Subject: Re: Looking for an 8 bit FDC... > From: Jules Richardson <julesrichardsonuk at yahoo.co.uk> > Date: Tue, 25 Oct 2005 18:43:13 +0100 > To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> > >Allison wrote: >>>Subject: Looking for an 8 bit FDC... >>> From: Jules Richardson <julesrichardsonuk at yahoo.co.uk> >>> Date: Tue, 25 Oct 2005 17:28:35 +0100 >>> To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> >>> >>> >>>OK, I'm wanting to build a board with an 8 bit CPU (probably Z80, >>>possibly 6502) and a floppy controller IC on board with the intention of >>>hanging it off my PC (via serial or parallel, undecided yet) and >>>allowing me to read and write *most* formats from various 1980's 8 bit >>>micros... >>> >>>Intel's 8271 looks like a possibility at the moment, but I thought I'd >>>poll the list for alternative ideas too. FM support is of course >>>critical - MFM is less of an issue as the host PC can handle that. >> >> >> ick poo.. The 8271 was not widely used especially on 8bitters. If your >> serious then 1793 that was common as house flies and does most all soft >> formats. > >Ahh, not had experience of that one before (I don't think anyway). 177x >was pretty common in machines over here, and the 8271 gets used in a lot >of Acorn hardware which is why I'm used to it... the Acorn is one of the few that used it. The 8271 was rare here compared to 1771 and 1793. >> Seriously 32kbyte static ram chips are easy to get (JDR and other have them) >> and EEprom (small is 2k and 8k are easy to find). > >Well part of the plan is to raid the junk pile and at least put some of >it to use, which would likely mean a 2732 EPROM for on-board ROM and >6116 SRAM chips for memory - latter subject to power requirements and >board space though. I know I've got quite a few of them kicking around, >but they're physically large chips and not *that* big a capacity (8kbit >or 16kbit I think, going from my hazy memory...) The 6116 is a great part and 4 of them are enough for a track level buffer and another 2 would provide adaquate code space. >Of course I've got a boatload of various DRAM chips though, so if the >Z80 does provide pretty much all the refresh needed then maybe that's a >better bet. GO TO Gaby's site and look for Tim Olmstead DRAM article. It covers DRAM interface in the context of Z80 systems and is very complete. >> Another way to do this is a small S100 bus with 16k of ram, a rom card >> Z80 cpu card and a serial board with one each of: >> >> NS* MDSA-4(a common hard sector that one does SD and DD) >> Tarbel 1771 based card (SD and really off 1771 specific formats) >> CCS 1793 based soft sector card. (most all softsector formats) >> Compupro 765 based card (why not!) >> > >Ahh, thanks for that list. We've got a truckload of S100 hardware at the >museum, so there's definitely a possibility there - I'm just not sure >without checking what FDC cards we have. I don't know what spare ROM >boards we'll have either (my programmer won't do three-rail devices, so >I'd need a board that'd take slightly newer EPROMs...) Or enough eprom to boot over wire. Everytime I need a system to do xxzzy I find enough peices in the S100 spares bin to build it with minimal fuss. Simple enough, anything with WD1771 will do SD, 1791/93 does SD and DD and there were some cards with 765 (Compupro) that do SD/DD. The real key is documentation, however for the popular cards its wasy to docs on line. >> If you stick to static parts and 6502 or Z80 the whole thing should be >> simple. Parallel port (bidirectional) will be faster but serial is easier >> though slower. > >Agreed :) I can't see parallel being complex though; I guess there's >just handshaking protocol to design on top of hooking the chip itself up >(unless I got for individual ICs to do the parallel interface), but it >doesn't need to be anything complicated. It's really traffic management, who talks first and when. ;) >I've got a few weeks until I'm back in the UK, so it gives me something >to ponder over in the meantime though :) Good luck, Allison

19 years, 1 month

Looking for an 8 bit FDC...

by ajp166＠bellatlantic.net

> >Subject: Re: Looking for an 8 bit FDC... > From: "Chuck Guzis" <cclist at sydex.com> > Date: Tue, 25 Oct 2005 10:46:34 -0700 > To: cctalk at classiccmp.org > >On 10/25/2005 at 5:28 PM Jules Richardson wrote: > >>Intel's 8271 looks like a possibility at the moment, but I thought I'd >>poll the list for alternative ideas too. FM support is of course >>critical - MFM is less of an issue as the host PC can handle that. > >The 8271 is a pile of worms. Don't even bother with it. The 8271 was SD only as well. >In a DIP package, if you want to restrict yourself to 5.25/3.5" MFM and FM >(but not HD) formats, the WD 1770/1772 is a nice compact (28 pin) little >chip that includes motor control lines as well a decent data separator for >FM and MFM. The Atari ST used it. If you want something a bit more >elaborate, the WD 279x series will handle most of what you need to handle, >but in a 40 pin package. All are easy to program and have Z-80 friendly >signals. The 279X is a more integrated 1793 so thats a good choice too. Watch out for the 1770/72 as not all flavors of them will work at 8" data rates. >The NEC 765-based chips (National 8473/8477, WD 37C65, Intel 82077, etc. >(the list is very long)) are built for the PC market and, when viewed from >the aspect of reading the largest number of formats, are quite quirky. >Some will read FM, but not write FM; some will drop the first sector if the >IAM missing (many WD-based vintage computers didn't bother with it), few >support 128-byte MFM sectors, etc. etc. Some of the older chips require >that you supply your own data separator. Given the choice, I'd stay away >from them. The 765A was least integrated but with the right external support more flexible than the 37C65 and later. The data seperator was a fairly simple circuit and could be done with a counter or for improved results with a latch and prom. Allison

19 years, 1 month

ID: Memorex 3266?

by tshoppa＠wmata.com

> picture: http://toresbe.at.ifi.uio.no/3266.jpeg This is a Fujitsu drive (not a 2444 but similar product line as the 2444, maybe a 2436?) that Memorex relabeled. Most of the ones I dealt with were Pertec Formatted (two 50-pin cables) and did 1600 and 6250. Some had cache cards, some had outboard third-party Pertec Formatted to SCSI converters. 2444's were especially popular with Sun VME systems. Tim.

19 years, 1 month

ID: Memorex 3266?

by toresbe＠ifi.uio.no

Hey, I've come across a Memorex 3266 half-inch tape drive (well, actually several, but only one seems near to operable condition). picture: http://toresbe.at.ifi.uio.no/3266.jpeg Anyone recognize it and know what densities and interface(s) it used? Guesses are also appreciated ;) It's an autoloader, right? I've been googling, and also bitsavers has nothing on it. Grateful for any hints. -toresbe

19 years, 1 month

Innovion PC info needed? Converting simms to dipps or Where do I find 1mx4 dipps?

by rmay635703＠aol.com

I have several old Innovion CASI Branded PCs computer photography PCs from the 80s (pictures here http://www.colortron.tk) I would like to expand the memory on several units to the full 4mb on the board, but I am finding it impossible to get 1mx4 20pin Dipp RAM chips. It would be nice if there were such a thing as a simm to dipp converter :) or sources of said chips. My other problem is with an old tektronix colorquick 4696 that works with my old photo systems. I need the dipp switch settings for it so I can get it to do a head clean (yes it has one) The printer is one of the old INK WELL type of printers and the heads clog easily, I ended up spraying the heads with distilled water and it worked for all of one copy. If you have a manual or dipp settings for this oldie it would be appreciated. Any ideas? Also on a side note I am looking for information, photos, really anything relating to the very old 1976 CASI / Innovion Apollo VPX Computer photo system. I have been trying to get one for years but everyone either tossed or sold their systems decades ago, the unit could take pictures and print them in B/W all with a whopping intel 8 bit processor. They were printed in 8pt text 14"x16". So your picture was ASCII ART!!!

19 years, 1 month

help requested in Arkansas rescue

by ajp166＠bellatlantic.net

> >Subject: Re: help requested in Arkansas rescue > From: "Teo Zenios" <teoz at neo.rr.com> > Date: Tue, 25 Oct 2005 12:21:16 -0400 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > > >----- Original Message ----- >From: "Allison" <ajp166 at bellatlantic.net> >To: <cctalk at classiccmp.org> >Sent: Tuesday, October 25, 2005 10:10 AM >Subject: Re: help requested in Arkansas rescue > > >> One good reason is that someday resources will appear to fully utilize it. >> That can also be read as keeping it from the scrap heap until such time. >> >> The other which is ugly is people storing and loosing to financial >> disaster or other physical disaster(weather, flood or fire) large amounts >> of hardware that end up as scrap. >> >> I've had to pass on gathering some hardware for lack of long term >supportable >> space and in other cases where I've collected more than I could sold off >excess >> so it would not be lost to the trash. I've also had hardware that I did >trash >> as likley of little to no value historically or as $$$ (mostly PCs of the >late >> XT clone and AT clones and the 386s). To me long term supportable space >for >> systems and board is stuff that can be accessed fairly easily and allows >actual >> test, repair and use. >> >> >> >> Allison > >Do you mean you save items at your own expense because someday some museum >might want it, or you intend to hit the lottery and move the machine to a >facility setup for it and other gems? None of the above though those are possible. It's more like I have a collection of systems and boards that are actively if only intermittently used. The key is functional and usable. the latter requires some space and local storage. >Personally anything with real historical value should be in a museum where >others can see it and learn about it. Most items that end up in a personal >collection that are not mainstream collectable just end up getting trashed >when that person dies or if lucky some other collector gets to hide it in >their warehouse away from view until they too die (or lose funding for the >storage). My evenual demise is provided for. As to historical, I have stuff I've used some since day one (Altair 8800 sn200 that no ware hear original) and some I've built. Most of the real history is lost just looking at it. It's what I did, why and how the equipment and I were invoved with various things. Same for the library of documentation tt's there to allow me to research, repair and occasionally relax with. >I have about all the machines I can setup and run without tripping over them >or using living space for their storage, although I need to rethink my >magazine and software storage methods. I'm at saturation. Occasionally I reorganize or mod a closet and get some space. >I guess the reason I replied to begin with is that while a Cray system does >sound cool in the geek sense (I picture circuit boards immersed in >fleuro-inert when I hear the name) I just don't see the average collector >having the time and resources to get it running and actually do something >with it. Once the cool factor wears out what are you getting out of having >the thing in storage? Thats a personal question I suspect. But with some machines its preserving the last known or one of the very few. PDP12s were never common and few are operable that do exist. Whos got a complete IBM360?? The Cray was only a few in existance and fewer remain. If your lucky enough to snag one and store it.. there's something special about the last one. Allison

19 years, 1 month

Releasing OS/2

by ajp166＠bellatlantic.net

> >Subject: Re: Releasing OS/2 > From: woodelf <bfranchuk at jetnet.ab.ca> > Date: Fri, 14 Oct 2005 15:21:24 -0600 > To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> > >Allison wrote: > >>My original intent was limited to OSs that were operable on PCs. If >>there is OS/9 for PC then by all means but I'd suspect comparison would >>be to unix/linux rather than Dos/win. >> >> >> >Circuit Cellar had a Z8000 and on card for the PC once. Does anybody >remember >just what it ran? Other than 386's was there any other add on cards for >the PC? Cards to add other CPUs to PC are many. At any time there were: 8751 (multiples for Mandelbrot calulations) Z80 Other X86 Z8000 68000 16032 T-11 (PDP-11) All come to mind. Many had no OS as they relied on the host processor for support. Allison

19 years, 1 month

help requested in Arkansas rescue

by ajp166＠bellatlantic.net

> >Subject: Re: help requested in Arkansas rescue > From: "Teo Zenios" <teoz at neo.rr.com> > Date: Tue, 25 Oct 2005 09:43:50 -0400 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > > >----- Original Message ----- >From: "Gordon JC Pearce" <gordonjcp at gjcp.net> >To: "General Discussion: On-Topic and Off-Topic Posts" ><cctalk at classiccmp.org> >Sent: Tuesday, October 25, 2005 8:26 AM >Subject: Re: help requested in Arkansas rescue > > > >> Does the storage locker cost less than the equivalent amount of aggro >> from dragging a Cray home? How many peace offerings has it saved you? >> >> Gordon > >What would be the point of having the machine in a storage locker unpowered >and far enough away that you will rarely go there to look at it rust? One good reason is that someday resources will appear to fully utilize it. That can also be read as keeping it from the scrap heap until such time. The other which is ugly is people storing and loosing to financial disaster or other physical disaster(weather, flood or fire) large amounts of hardware that end up as scrap. I've had to pass on gathering some hardware for lack of long term supportable space and in other cases where I've collected more than I could sold off excess so it would not be lost to the trash. I've also had hardware that I did trash as likley of little to no value historically or as $$$ (mostly PCs of the late XT clone and AT clones and the 386s). To me long term supportable space for systems and board is stuff that can be accessed fairly easily and allows actual test, repair and use. Allison

19 years, 1 month

Fan for DEC H7861 power supply?

by ajp166＠bellatlantic.net

> >Subject: Re: Fan for DEC H7861 power supply? > From: David Betz <dbetz at xlisper.mv.com> > Date: Tue, 25 Oct 2005 10:57:54 -0400 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >Okay, I'm stupid! I forgot to write down which direction the fan was >moving air when I removed the defective fan. It looks like the H7861 >has two fans one of which sucks air in and the other blows it out. Is >that correct? Or do they both suck air in? The one I'm replacing is >the one that is mounted at an angle. The one I haven't touched is >setup to suck air into the box. How should I mount the diagonal fan? >To suck air in or out? Same direction. Allison > >Thanks, >David > >On Oct 23, 2005, at 3:36 PM, Allison wrote: > >>> >>> Subject: Re: Fan for DEC H7861 power supply? >>> From: David Betz <dbetz at xlisper.mv.com> >>> Date: Sun, 23 Oct 2005 14:55:07 -0400 >>> To: "General Discussion: On-Topic and Off-Topic Posts" >>> <cctalk at classiccmp.org> >>> >>> I found a replacement fan for the H7861. It is the same size and same >>> wattage but it has only three blades instead of the five that the >>> original had. Is this likely to produce enough air flow to prevent >>> the system from frying itself? Or should I keep looking for a five >>> blade fan? >>> >>> >> >> I'd use it for testing and try to find the right one. >> >> >> Allison >>

19 years, 1 month

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test-drb October 2005