test-drb November 2010

test-drb@ccmp.vtda.org

162 participants
241 discussions

by pontus＠update.uu.se

2010-11-05 23:42, Tom Gardner skrev: > > Good eyes! > > When I look more closely, it seems that the X and Y lines are under > the center sections but no cores, ergo, 16 core mats. I'd like to see > a real one to confirm. > > Tom > The reason I noticed is that I looked at a core memory board for a PDP-10 just the other day, it had one half section with missing core. I could take a picture if you like. /P

13 years, 6 months

Tek 4051 in Austin

by swtpc6800＠comcast.net

The TEK 4051 is a Graphics Terminal with BASIC in ROM, It used the Motorola 6800 microprocessor. I did a Wikipedia article on the MC6800 and illustrated it with several old advertisements including the first M6800 ad and a Tektronix 4051 ad. Here is the article http://en.wikipedia.org/wiki/Motorola_6800 And here is the TEK 4051 ad. http://commons.wikimedia.org/wiki/File:Tektronix_4051_ad_April_1976.jpg Michael Holley -----Original Message----- From: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org] On Behalf Of steve shumaker Sent: Friday, November 05, 2010 2:37 PM To: On-Topic and Off-Topic Posts Subject: Tek 4051 in Austin Tektronix 4051 functioning system??? Austin C/L #2043597225 looks in fair shape.? supposedly working...?? wants $150 cash and? pick up only steve

13 years, 6 months

HP9845 design article in EDN

by cclist＠sydex.com

No one seemed to notice this, but I thought I'd post it for Tony's edification. It's a story in the October 7 EDN from the "Tales from the Cube" back section and deals with solving a problem with the I/O board of the HP9845: http://bit.ly/cNwokC (it's a PDF) Enjoy, Chuck

13 years, 6 months

MFM and ESDI SCSI bridge boards (was Re: SCSI emulator)

by ethan.dicks＠gmail.com

On 11/5/10, Jules Richardson <jules.richardson99 at gmail.com> wrote: > Dave McGuire wrote: >> On 11/5/10 2:00 PM, Jules Richardson wrote: >>> It's a bit more murky than that (albeit a related issue) because a lot >>> of the bridge boards expect a vendor-specific command to tell them the >>> drive geometry of the attached drive... >> >> MFM- or ESDI-to-SCSI bridge boards (Adaptec ACB-4000, Emulex MD21 if >> memory serves) are weird to begin with... > > I think the Adaptec was one of the most sane boards out there I do have some experience with a couple of them, primarily the ACB-4000 > IIRC it stores > the drive geometry on block zero of the drive at format time, then at > power-on fetches that block back and initialises itself with the loaded geometry. That sounds somewhat familiar to me, but I wouldn't have been able to have said that's what it did without looking it up first. > I can't remember if it just hides the first block from the user, or hides the > whole track. I really can't remember that detail - been way too long, but if I had to guess, I'd guess "block" since I have a fuzzy memory about some detail about moving, say, an ST225 on and off an ACB-4000 and a different kind of controller (an XT MFM card most likely, possibly a WD WX-1 or Everex clone). > I think the board responds to Inquiry, too (although it just returns "ACB > 4000" rather than anything to do with the geometry of the attached drives) That also sounds familiar (having played at the low-level back in my early Amiga days). > I've not played with the Emulex boards - I think the only ones I have are > tape bridges rather than disk. I have a couple of the Emulex bridging boards from the Sun-3/early Sun-4 days, but I never had to set them up - they were black (beige, really ;-) boxes to me. I just stuck them on a Sun box and don't remember any special fiddling. > The Xebec and Omti boards seemed reliable, but their SCSI implementations > were > a little lacking (one of them I think had the option of a user-supplied ROM > with the expected disk geometry encoded into it, but it still wasn't "SCSI > enough" to work with a modern system) I think I tried to fiddle with an Omti board once but didn't achieve enough success to use it. One reason I tried was it was a combo hard-drive/floppy drive model. It would have been handy, but alas no. It's likely I was running into one of those "almost-SCSI" problems and lacked sufficient documentation. Since I moved from PETs and C-64s and small DEC machines first to Amigas and Macs, then much later to PCs, I was very happy when embedded SCSI drives displaced all the Adaptec and Emulex and Xebec and Omti boards - much easier to set up and move from environment to environment. -ethan

13 years, 6 months

Kaypro "Profile" Magazines free+postage from 95006

by shumaker＠att.net

available for free + postage from 95006: several partial years of the KayPro focus magazine "Profiles": Dec/Jan 85 ?Dec 85 (full year) Jan-Mar 86; Jul 86 Jun ?Jul 87; Sep ? Dec 87 Jan ? May 88 Note that these issues are all available as scanned docs (or will be shortly) on Gene Buckle's site at www.retroarchive.org. But if you gotta have an original.... I figured I'd offer them here before they get recycled. mags are in good shape. steve

13 years, 6 months

Bill's PDP-11/34A

by bqt＠softjar.se

On 2010-11-03 18:00, Ethan Dicks<ethan.dicks at gmail.com> wrote: > On 11/3/10, B Degnan<billdeg at degnanco.com> wrote: >> > Here are pictures from the system as I first got it, if it helps with >> > the card order/comparison purposes. Note that some cards are not >> > installed in the backplane. >> > http://vintagecomputer.net/digital/pdp11-34a/before/ > Do you have packs for your RL01 drives? Hopefully the packs were > removed and the heads locked for transport. Good point. There is a transport lock for RL drivers, that should be in place when transported, and which should be remembered to be moved out of the way when used. > An 11/34 w/RL01 is a nice little RT-11 system, though it'd be a bit > cramped for 2.9BSD (both in terms of disk and RAM). You could > probably also run an older version of RSX-11/M on it too. I think we > ran something around RSX-11/M 4.0 or 4.1 on ours in the mid-1980s. You can always get more disk. Easiest would just be an upgrade to RL02 drives... Also, current RSX-11M would also be happy on that machine, assuming he has the full 256K of memory. Once more possibly disk space being an issue, though. Johnny -- Johnny Billquist || "I'm on a bus || on a psychedelic trip email: bqt at softjar.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol

13 years, 6 months

PDP-11 firsts?

by bqt＠softjar.se

On 2010-11-01 00:02, ard at p850ug1.demon.co.uk (Tony Duell) wrote: >> > On 2010-10-30 01:12,ard at p850ug1.demon.co.uk (Tony Duell) wrote: >> > >>> > > >>>>> > >> > I have not seen anyone comment any of the other things I listed as >>>>> > >> > possible firsts on the PDP-11. >>>>> > >> > Can anyone come up with an earlier machine that used condition codes? >>>>> > >> > How about general registers with addressing modes, which is totally >>>>> > >> > orthogonal? How about having the PC as a general register? >>> > > The Philips P800 series has the PC as a general register (register 0). >> > >> > Could you use it like any other register? > There were some restrictions. I don't think you could shift it (at least > ont on the P850). But for many instructions it was just another register. Cool. So you could add to it, index by it, and so on? >>> > > There are 16 registers, some instructions can only use the first 8, others >>> > > can use all 16. Addressing modes (simpler than the PDP11, I admit) are >>> > > pretty much orthogonal. >> > >> > Sounds like the registers were atleast not as orthogonally used as on a >> > PDP-11. If an instruction could take a register, it could take any >> > register. And all addressing modes are valid (well, almost) anywhere. > I think all P800 instructions that had addressing modes could use any > addressing mode. Any instruction with 4-bit register fields could use any > register. Any instruction with a 3 bit register field could use any of > the first 8 registers. And IIRC, like the PDP11, the addressing modes > commonly known as 'immediate' and 'absolute' were a couple of the other > addressing modes with the register specified as 0 (=PC, of course). > > I guess the P800 wasn't totally ortogonal but it was a lot more > orthogonal than many other machines. Indeed sounds nice. When did the machine appear? >>> > > What do you mean by condition codes here? >> > >> > The four low bits of PSW. > Err... I don;t think that's helpful. Quite a lot of machines with a > status register have a 'low 4 bits' of it:-). But that doens't make them > condition codes. Similarly uf you hapopen to implement the same > functionality using other bits of a status registers, doesn't that make > them condition codes? > > What I was asking was what fucntionality do you require of these > condtiion codes other than there being conditional jumps on carry, zero, etc? Sorry. I was just being lazy, and trying to explain condition codes by referring to what they are on the PDP-11. To try and be more specific then: condition codes are bits that are set/reset as a result of operations performed by the processed, and upon which you can the make conditional branches/jumps on. As opposed to, for example, a PDP-10, where you instead encoded the condition within the instruction, along with a register to test upon. Johnny -- Johnny Billquist || "I'm on a bus || on a psychedelic trip email: bqt at softjar.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol

13 years, 6 months

PDP 11 Core Memory - H214 Memory Stack

by thomas.gardner＠sbcglobal.net

There are several pictures of an 8 KiWord H214 Memory Stack posted on the Internet, for example, see http://www.conservatique.com/_/rsrc/1251146207239/pdp/pdp-1105/H214-c... <http://www.google.com/url?sa=D&q=http://www.conservatique.com/_/rsrc/125114 6207239/pdp/pdp-1105/H214-core-plane%3Fheight%3D167%26width%3D200&usg=AFQjCN GgCgWQk-XDZ2griejhV44yO10CAQ> At least one DEC manual describes the H214 as having "16 memory mats arranged in a planar pattern" but the photo referenced above (and many others) show 20 memory mats arranged in a two x ten planar pattern. Two by ten is a very strange array for a machine that has a 16 bit word or 18 bits in one with the byte parity option. Can anyone explain what is going on? Tom Note this is also posted to alt.sys.pdp11 <http://groups.google.com/group/alt.sys.pdp11>

13 years, 6 months

68K

by bqt＠softjar.se

On 2010-11-01 18:00, Ethan Dicks<ethan.dicks at gmail.com> wrote: > On Sat, Oct 30, 2010 at 6:51 AM, Johnny Billquist<bqt at softjar.se> wrote: >> > On 2010-10-30 01:12, Ethan Dicks<ethan.dicks at gmail.com> wrote: >>> >> I know it works well enough in early Sun workstations and the AT&T >>> >> Unix PC (3B1/7300), but I have no knowledge of any required >>> >> workarounds due to possible bugs. >> > >> > Yes, the 68010 worked fine with demand paging. The 68000 did not. >> > Neither of them implemented instructions restarts, though. As noted below, >> > the 68010 did instuction suspension instead. > Yes. I was previously unaware of the distinction but did know what > the 68000 could not do that the 68010 could. We were at the same level, then. :-) >> > The "interesting" workarounds that I've hear of are actually 68000-related... >> > Using their own designed MMU (there were none from Motorola for the 68000), > What about the 68451? (we had one in a prototype product design in > 1984/1985 that never made it to market) > > It wasn't terribly popular, but it did exist. Tried to look it up on the net, and I'm unsure if it really was usable on the 68K. It would appear that it did hit the market, and if you had a 68010 in combination with this chip, you could implement virtual memory, since you could recover from page faults. However, there were also third party MMUs competing with the Motorola chip, which might explain why it was rather uncommon. Performance wise, the 68010 in combination with the 68451 appear to not have been that impressive. >> > and a second CPU, Apollo made the primary CPU stall on a page fault, and the >> > secondady CPU wake up. The secondary CPU could then do a page in... > That sounds like the design of the Perkin-Elmer workstation I have - > two 68000s, one for running the OS, one for paging. I wouldn't be surprised to learn that SUN did something similar as well... Johnny -- Johnny Billquist || "I'm on a bus || on a psychedelic trip email: bqt at softjar.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol

13 years, 6 months

Moving Home - repeat

by williams.dan＠gmail.com

Hi, I still have : An Octane Sun Blade 2000 Dell Itanium blade (Heavy) 2 x Dual machine blade sparc machines I hate to do this but if they are not claimed by Monday they will have to be thrown out. I have also found a processor card still in it it's box for a Vax 4000/500 if anyone is interested. Dan

13 years, 6 months

← Newer
1
...
17
18
19
20
21
22
23
24
25
Older →

Jump to page:

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

1997

test-drb November 2010