[cctalk] Re: Z80 vs other microprocessors of the time.
On Mon, Apr 22, 2024 at 2:30 PM Paul Koning via cctalk wrote: > Anyway, I would think such a small microprocessor could emulate a PDP-11 just > fine, and probably fast enough. The issue isn't so much the instruction set > emulation but rather the electrical interface. That's what would be needed > to be a drop-in replacement. Ignoring the voltage levels, there's the matter > of implementing whatever the bus protocols are. Emulating an F-11 chip or a J-11 chip is certainly possible with a modern MCU, just need TTL-friendly I/O. F-11 is 40-pins (and can have additional instructions added by adding microcode ROMs next to the CPU) and the J-11 is 64 pins on a fat chip carrier. > Possibly an RP2040 (the engine in the Raspberry Pico) would serve for this, > with the PIO engines providing help with the low level signaling. Sounds > like a fun exercise for the student. Could be a good start but would still need level shifters. J-11 runs at 15-18Mhz for an idea on how fast the bus implementation has to be. -ethan
[cctalk] Re: PDP-11 thingy. What is it?
On Wed, Apr 10, 2024 at 8:07 PM W2HX via cctalk wrote: > 1. I have read that the card and the drives were compatible with the dec rx02 > drives. Why would the CRDS even bother to redesign a card where DEC had > perfectly good working ones? Anyone know if there is any value in keeping the > FC-202 or just keep with the DEC cards? The easy first answer is DEC's drives were expensive so there was room for competition to bring in a less expensive product and then _they_ would get the profits. The second answer is that DEC's implementation was basic - read and write single-sided floppies and that's it - no media (re)formatting. Third parties could add features to extend what DEC had. The DEC implementation relied on a custom processor board inside the disk drive and a unique/proprietary way to have the controller tell the drives what to do. By the late 80s. Shugart interface drives were plentiful and processors like the Z-80 were totally capable so there were several RX01 and RX02 imitators. I have at least one Qbus card that just has a Shugart interface and was connected to a standard floppy drive mechanism (and it can low-level format disks). In order to work with existing drivers, though, the third party cards did have to emulate them at the I/O register level but as long as it's registers on one end and 8" media on the other, they were free to reimplement the middle part. -ethan
[cctalk] Re: Drum memory on pdp11's? Wikipedia thinks so....
On Mon, Apr 15, 2024 at 12:53 AM Christopher Zach via cctalk wrote: > Was reading the Wikipedia article on Drum memories: > > https://en.wikipedia.org/wiki/Drum_memory#External_links > > And came across this tidbit. > > As late as 1980, PDP-11/45 machines using magnetic core main memory > and drums for swapping were still in use at many of the original UNIX > sites. > > Any thoughts on what they are talking about? I could see running the > RS03/RS04 on a 11/45 with the dual Unibus configured so the RS03's talk > to memory directly instead of the Unibus, but that's not quite the same > as true drum memory. Yep. > Closest thing I remember was the DF32 on a pdp8 which could be addressed > by word as opposed to track/sector. Yes. And the RF series (RF08 and RF11). UNIX on the PDP-11 in 1972 required an RF11 for swap. As mentioned in other replies, the media isn't cylindrical but it behaves logically like a drum. -ethan
[cctalk] Re: Voyager spacecraft computer
On Fri, Mar 15, 2024 at 6:49 PM Charles Dickman via cctalk wrote: > Voyager 1 is in the news recently because of communications problems and > possible solutions. Is there an online source for documentation on the > Voyager systems, especially the computers and navigation systems? > > I have enjoyed reviewing the Apollo systems documentation on the Virtual > AGS Home Page and wondered if there were similar documents available for > Voyager. "NASA Contractor Report 182505 Computers in Spaceflight: The NASA Experience" More of a top-level tour of a number of platforms, it covers, in quite some detail, systems from Gemini to the Space Shuttle and mentions the RCA 1802 numerous times. Samples of some NASA DSLs (HAL/S and GOAL). Extensive citations and bibilography. Voyager and Galileo are covered in Chapter 6. Public domain. PDF link at: https://ntrs.nasa.gov/citations/19880069935 Excellent stuff in there. -ethan
[cctalk] Re: programming the IBM PC synchronous serial boards (Northstar Advantage project)
On Fri, Dec 22, 2023 at 10:20 PM Chuck Guzis via cctalk wrote: > Sync (Bisync, SDLC/HDLC) was fairly popular back in the day for linking > with mainframes. (Think, for example, IBM HASP). On PCs and the like, > the Intel 8251 was used a lot, but even the Signetics 2651 has the sync > mode, with the ability to recognize a double-byte sync. The COMBOARD line of Bisync and SNA protocol engines came out of the HASPBOX product, which was 100% DEC hardware, so we started with a COM5025 (same as at least one of DEC's sync seral boards) and we later moved to the Zilog Z8530 (but only ever used its second port as a local async debug port) > The protocol for any of the above higher-level protocols is fairly > complex and there are manuals for that Yeah, implementing Bisync from scratch on a new platform would be quite an effort. There are a few poorly-documented "gotchas" to work through/around. -ethan
[cctalk] Re: Intel 4004
On Mon, Nov 27, 2023 at 5:32 PM Rick Bensene via cctalk wrote: > Steve Lewis wrote: > > then like the 4004, we're struggling to find evidence of actual products > > that > > made use of them. Wasn't the 4004 used in some cash registers, street > > lights, or > > some weighing machines? (I don't have any specific references, just > > recollections > from past reading) Over the years, I've found a 4004 in two commercial products - a 1970s non-UPC barcode scanner, and a commercial kitchen scale. I still have the PCBs for the scale (with the accessory chips). The barcode scanner was utterly dismantled 35 years ago. -ethan
[cctalk] Re: PDP11 and Ultrix 11
On Fri, Oct 20, 2023 at 1:46 PM Henry Bent wrote: > I have a SIMH installation of Ultrix-11 3.1 on RL02 drives. Two RL02s is > enough for a base system and four (which would be what the DQ614 provides, if > it worked) would be more than enough for sources and work, etc. Yes. 40MB should be plenty of room. 10MB was definitely not enough for 2.9BSD, but at the time, I only had one RL02 drive. > The Ultrix-11 RL driver does fancy things with overlapped seeks that I'm sure > works on real hardware but on the DQ614, not so much. Ah... I can see that. It wouldn't surprise me if the DQ614 got most of its development and testing with RT-11 in mind, and possibly some RSX-11. I remember that the DEC RL controller (at least for PDP-11, not as sure about the RL8A) did support some pretty handy things for a multi-user OS, like overlapping seek, but I think in all the years I worked with DEC gear, only a few machines had multiple RL drives. Mostly I saw them as data transfer devices or for primary storage on small (single-user) systems. We did have one larger system, an 11/24 with four RL02, running RSTS/E and whatever we were using for accounting software. I didn't work on the machine myself except to physically disconnect and pack and move it from one site to another when we consolidated our operations back into one building. -ethan
[cctalk] Re: PDP11 and Ultrix 11
On Wed, Oct 18, 2023 at 10:21 AM Henry Bent via cctalk wrote: > Interesting. My Dilog DQ614 (ST506 emulating RL02s) specifically does not > work with Ultrix, but does work with 2.xBSD and v7, so I would not > necessarily assume that a third-party board was going to work with > Ultrix-11's drivers. I have personally installed 2.9BSD on an 11/24 with RL11 and RL02 so I _know_ that works (and I would expect the DQ614 to work there too). I have a DQ614 but the Rodime drive that came with it was toast and I only recently got the RT11 utility to fiddle drives so I haven't ever tried to use mine. I may end up tossing an ST225 or ST241 on my DQ614 when I get around to trying it. I do not know what drives Ultrix-11 supports but it wouldn't be shocking to find that you can't use an RL02 as the root install device. An RL02 was only big enough for the base install of 2.9BSD and not big enough for base+sources so I was never able to rebuild my kernel (it all worked fine on an RK07 at work). In the past, I never did anything with 2.11BSD or Ultrix-11 because I didn't have a new enough setup (most of my gear came from the 70s and early 80s - no J-11 anywhere until recently). As mentioned, if it's a well-implemented MSCP SCSI controller (UC07, CQD220...), it should "just work" on any system there are MSCP drivers for. Cheers, -ethan
[cctalk] Re: 11/15, 11/20 systems and parts, more
On Fri, Oct 20, 2023 at 12:11 PM Jon Elson via cctalk wrote: > On 10/20/23 03:59, Michael Thompson via cctalk wrote: > > The RICM has an empty 11/20 chassis and the power supply. All it needs is > > the processor backplanes. Is there any chance you have a set of backplanes > > available? > > > I have a DD11-PK backplane (Part No. 70-11523) with a few > bent pins. None are bent so badly they can't be > straightened. From 11/04 or 11/34. Free if you pay shipping. DD11-PK is for 11/34 (top two slots for CPU). PDP-11/04 uses standard DD11-DK (single-board CPU, doesn't need special slots). The 11/20 is entirely different. It has three 4-slot backplanes for CPU boards with "random" wiring and Unibus out on AB of final slot. It would be unusual but not impossible to see the 11/20 CPU backplane assembly outside of a BA11-C cabinet. If one had 12 DEC backplane blocks, one could make a replacement but it would be quite an undertaking. Might be easier to make a PCB-based replacement with modern connectors. Could also upgrade power input scheme while at it. -ethan
[cctalk] Re: Apple 1
On Thu, Aug 17, 2023 at 2:34 PM Bill Degnan via cctalk wrote: > On Thu, Aug 17, 2023 at 2:28 PM Ethan Dicks via cctalk < > I should add that part of the fun is to locate parts for free or cheap from > dead or unimportant period electronics, cards, etc. In that way slowly > building up what is needed to complete parts of the Apple I replica one > piece at a time. I am not in a rush. I am totally doing that, but outside of early-70s dumb terminals and maybe some early electronic sound effect devices, there aren't a lot of places to encounter massive PMOS shift registers. RAM and generic logic are easy enough to find with patience. Closed TI sockets are also findable, but they were awful then and haven't improved one bit with age. -ethan
[cctalk] Re: Apple 1
On Sat, Aug 5, 2023 at 6:11 PM Cameron Kaiser via cctalk wrote: > I have an IMSAI as well, but for me my favourite computer of that era is the > KIM-1, and that's such a simple design there are tons of implementations I only recently got a KIM-1 (at VCF East). It's been on my list for a while and I was able to get it in a swap not eBay prices so I'm twice as happy. > (though I prefer the original since some of them apparently have edge-case > incompatibilities). I've had a replica for a while and for running code it's an adequate match, but, yes, there are some quirks that do matter. One of the biggest implementation differences from 1976 to today totally matters to me - I have an old TVT 6-5/8 Cheap Video board I got as a kid that needs the "upstream tap" to present different memory contents to the CPU and to the video board, and that in turn depends on how and where the bus is buffered. Most of the simple replicas are either total hardware emulation (KIM Uno) or are so small that they just don't have the same bus buffer arrangement so that would have to be hacked in. Now that I _have_ a KIM-1, I can look at how bad the hackery is and finally see this board in action. -ethan
[cctalk] Re: Apple 1
On Sat, Aug 5, 2023 at 4:08 PM Bill Degnan via cctalk wrote: > But...because the apple I is so valuable people have been motivated to > produce really nice replica motherboards. The replicas give many the > chance to experience the Apple I at a reasonable price I have a bare replica PCB. It's proving difficult to stuff without spending a wad. > It's fun to find original parts and sockets to try to get > a replica as close as possible to an original. You can do that for less than buying an original but it's still $$$ in part because of the rarity of the oddball shift registers, etc., and in part because of the demand for specific package types and date codes to achieve the closest match to an original. Just the ICs alone are hundreds of dollars, the large caps are tens of dollars and even that exact heat sink isn't exactly cheap. My classic interests are wide and varied (as demonstrated by what I bring to VCF) and totally encompass all sorts of 6502 systems. The specific interest the Apple 1 has for me is how screwy the video implementation is (cheap in its time but an evolutionary dead end) and how much it can do with 256 bytes of ROM and 8K of RAM. I would like to be able to build up my board just to watch it run, but outside of that, a non-exact replica (typically using a modern microcontroller to implement the stages of shift registers) still gets the job done for hacking raw 6502 code. I certainly believe in running old systems (I use machines from the 60s and 70s all the time) but in the case of a computer that costs more than my house, I'd probably lock it up in a vault and only take it out for special occasions too. -ethan
[cctalk] Re: Old Professional/350 software, any of this out there
On Thu, Jul 27, 2023 at 11:28 AM Mattis Lind via cctalk wrote: > Perhaps it would be a good idea to upload de-interleaved images along with > the .IMD, .DSK and a quick document that explains the situation. Otherwise > we will have this coming up every now and then and people will scratch > their heads until Paul explains the details. I concur. I have had this exact topic come up multiple times over the past 18 months. It's "documented" but not so plainly that most new users will ever find it. Mostly I hear "I converted IMD files to BIN but Simh can't mount them", over and over. -ethan
[cctalk] Re: Restoring Ultrix-32m 1.2 Floppies
On Mon, Jul 17, 2023 at 1:05 PM Paul Koning via cctalk
wrote:
> > On Jul 17, 2023, at 12:51 PM, Ethan Dicks via cctalk
> > wrote:
> >
> > On Mon, Jul 17, 2023 at 12:48 PM Ethan Dicks wrote:
> >> From: http://www.chdickman.com/pdp11/pro380.txt
> >>
> >> "The RX50 floppy starts at track 1. Track 0 is logically placed after
> >> track 79. The sectors are...
> >
> > It should be "... interleaved 1, 3, 5, 7, 9, 0, 2, 4, 6, 8..." There
> > is no "sector 10" when counting from 0.
> >
> > -ethan
>
> I don't know what to make of that web page's description, it certainly
> doesn't have much connection to reality. Are those numbers supposed to
> represent the placement of logical sector numbers onto the physical track?
> If so, they show 5:1 interleave rather than 2:1 interleave. Or do they
> represent the physical sector numbers for consecutive logical sectors? If
> so, it seems to be backwards.
It looks like it represents how to go from a physical track to get
things back in the logical order that one would see from a PDP-11 or
VAX on real hardware - i.e., the boot block (if any) is the very first
thing you encounter.
I agree, it's not a 2:1 interleave in any classic sense.
> The actual algorithm is what I wrote in my previous email, which you can also
> find in my RSTSFLX tools. That has been tested against real world RX50
> floppies, and against the source code of the RT11 RX50 driver.
Chuck Dickman's algorithm is in lbn2rx50.c
#define RX50_TRACKS 80
#define RX50_SECTORS 10
int interleave[] = { 0, 2, 4, 6, 8, 1, 3, 5, 7, 9 };
track = lbn/RX50_SECTORS;
track = (track + 1)%RX50_TRACKS;
sector = lbn%RX50_SECTORS;
sector = (interleave[sector] + 2*(track - 1) + RX50_SECTORS)%RX50_SECTORS;
-ethan
[cctalk] Re: Restoring Ultrix-32m 1.2 Floppies
On Mon, Jul 17, 2023 at 12:48 PM Ethan Dicks wrote: > On Mon, Jul 17, 2023 at 12:28 PM Henry Bent via cctalk > > I'm almost thoroughly unfamiliar with IMD - is there some obvious > > extraction/conversion option that I am missing here? As mentioned previously, yes. There's an additional step that has to happen to any direct imaging of RX50 disks. John Wilson's PUTR happens to do this convolution internally. If you desire is to snapshot physical media for rewriting later, IMD is excellent. If you want logical-block-order files for simh, you need one more step (keep reading). > Were these disks actually imaged correctly? I would appreciate any > suggestions. Yes they were. > From: http://www.chdickman.com/pdp11/pro380.txt > > "The RX50 floppy starts at track 1. Track 0 is logically placed after > track 79. The sectors are interleaved 1, 3, 5, 7, 9, 0, 2, 4, 6, 8, > 10. The track shift and interleave must be taken into account when > moving disks between real PDP-11 and emulators." I have had good luck with a secfor convolver from the same page as this comment: http://www.chdickman.com/pdp11/lbn2rx50.c It will go both ways, to and from physical block order and logical block order. Cheers, -ethan
[cctalk] Re: Restoring Ultrix-32m 1.2 Floppies
On Mon, Jul 17, 2023 at 12:48 PM Ethan Dicks wrote: > From: http://www.chdickman.com/pdp11/pro380.txt > > "The RX50 floppy starts at track 1. Track 0 is logically placed after > track 79. The sectors are interleaved 1, 3, 5, 7, 9, 0, 2, 4, 6, 8, > 10. The track shift and interleave must be taken into account when > moving disks between real PDP-11 and emulators." Let me point out that this webpage quote accidentally lists too many sectors for an RX50. It should be "... interleaved 1, 3, 5, 7, 9, 0, 2, 4, 6, 8..." There is no "sector 10" when counting from 0. -ethan
[cctalk] Re: Restoring Ultrix-32m 1.2 Floppies
On Mon, Jul 17, 2023 at 12:28 PM Henry Bent via cctalk wrote: > I just noticed that images of a full RX50 floppy set for Ultrix-32m 1.2 was > posted on Bitsavers ( > http://bitsavers.trailing-edge.com/bits/DEC/vax/ultrix/1.2/ULTRIX-32M_V1.2_RX50_1986.zip > ). I am having difficulty parsing these images into a usable raw format > for SIMH. You are not the first to encounter this. > Oddly though, in the "raw" dump the bootloader doesn't > start until 0x1400, and a number of the other disks I looked at appear to > have odd holes/zeroes in them. IMD format dumps of the 1.2 disks are > provided but when I converted the IMD format to a raw image I got the same > issue. Yes. IMD->raw just decompresses the IMD format back into the exact number of bytes, in the same order, of the original media. Keep reading for why this is not sufficient... > I'm almost thoroughly unfamiliar with IMD - is there some obvious > extraction/conversion option that I am missing here? Were these disks > actually imaged correctly? I would appreciate any suggestions. This is not an IMD issue. IMD files are numbered as they come off the media and can be written back out, as is, to make physical media, which was the primary purpose. For nearly all cases, this also happens to match sequential sector order so that the same data can be used for emulators (simh and others). The one case where the two situations don't match is the RX50. What DEC did was to put a software-defined sector interleave and track shifting into their RX50 controllers (RQDX1 et al). In addition to the sectors on the disk not being in "logical filesystem order", track 0 gets moved to the end of the list From: http://www.chdickman.com/pdp11/pro380.txt "The RX50 floppy starts at track 1. Track 0 is logically placed after track 79. The sectors are interleaved 1, 3, 5, 7, 9, 0, 2, 4, 6, 8, 10. The track shift and interleave must be taken into account when moving disks between real PDP-11 and emulators."
[cctalk] Re: Don Lancaster has passed away at 83
On Thu, Jul 6, 2023 at 6:26 PM Bill Degnan via cctalk wrote: > I am going throw out a Jim Butterfield too I never got to meet him or correspond with him directly, but through his articles and his work with TORPUG, he absolutely had a huge indirect influence on my early years. I did learn plenty from Don Lancaster too, but it was more general knowledge than anything. I don't think I ever read something of his that I didn't learn something from. -ethan
[cctalk] Re: Bob Applegate passed away
On Sun, Jun 18, 2023 at 7:56 PM Cameron Kaiser via cctalk wrote: > > Just letting everyone know that Bob Applegate passed away a few days ago. > > He had been battling cancer for some time. He was involved with vintage > > computing for some time. Here is his website: http://www.corshamtech.com/ > > > > This is the website for his memorial: > > https://everloved.com/life-of/robert-applegate/ > > Bob made great stuff. I bought a few KIM boards off him a few weeks back. He > said the treatment wasn't going well, and it didn't seem like it would be > long. Yeah. I saw his update from Memorial Day weekend where he said he wasn't feeling well. On top of everything else, sounded like it was close, and it was. Since I got a KIM-1 at VCF East and since Bob wasn't there, I made a point of ordering some accessories from Bob back in April. Doubly glad I did. > I'm glad he's at peace. Indeed. -ethan
[cctalk] Re: Did Bill Gates Really Say That?
On Fri, Jun 16, 2023 at 10:26 PM Tomasz Rola via cctalk wrote: > I guess we are all prisoners of our own mental frame. I recall that > Ken Olsen (DEC founder), once quipped "There is no reason for any > individual to have a computer in his home." - that was in 1977, > according to wikiquote: > > https://en.wikiquote.org/wiki/Ken_Olsen One version of that story is he told it to David Ahl who was trying to pitch a <$2000 PDP-8 for the home market (IIRC a configuration like a 4-slot box with a KK8A, some basic I/O and a smallish MOS RAM card - too small to compete with a "real" PDP-8 system). Ken's reaction was an element of what led to David going off to found Creative Computing, as the story goes. -ethan
[cctalk] Re: Did Bill Gates Really Say That?
On Wed, Jun 14, 2023 at 12:21 PM Sellam Abraham via cctalk wrote: > Based on other videos of Dave's that I've watched he doesn't really know > what he's talking about so I wouldn't lend much credence to his apocrypha > either. Agreed. Some months back, Dave put out one of his videos with a click-bait headline that was, well, false. He did not respond well to that being pointed out. His "insider knowledge" hasn't impressed me. > > So I had always heard the quote "640KB is enough memory" being attributed > > to Bill Gates > > > > And apparently the man himself has denied it as well but it just will not > > go away... > > > > https://abcnews.go.com/Technology/PCWorld/story?id=5214635 It's entirely possible, even probable, BG didn't say exactly those words no matter what people think they remember. OTOH, I do remember, back in the day, that he _did_ make a similar statement, *but* unlike the myth, it wasn't to belittle PC users, but whatever he _did_ say was a caution to application programmers that the max available memory space _ought to_ be enough to write reasonable programs for the PC market, that there were ways to write programs that _would_ fit in 640K and you should be doing that. So I'm not gonna swear he said those words, I do remember something along those lines was said ~40 years ago. -ethan
[cctalk] Re: Getting floppy images to/from real floppy disks.
On Fri, Jun 2, 2023 at 4:38 PM Sellam Abraham via cctalk wrote: > On Fri, Jun 2, 2023 at 8:24 AM Ethan Dicks via cctalk > wrote: > > > I did see an actual 1970s station wagon loaded with RL02 cartridges > > once, pulled up at the dock of Baker Systems, the large Computer > > Science building at Ohio State (I suspect they were cleaning out a > > machine room and someone wanted the packs) > > It might've just been an enactment of the old adage for a video project. > Maybe they dumped the carts afterwards? :( This was in the late 80s when packs and such were still somewhat desirable. I did not see any cameras on the dock. -ethan
[cctalk] Re: Getting floppy images to/from real floppy disks.
On Thu, Jun 1, 2023 at 4:45 PM Alexander Schreiber via cctalk wrote: > On Wed, May 31, 2023 at 05:01:34PM -0700, Fred Cisin via cctalk wrote: > > What is the bandwidth of a station wagon full of 1TB Mcro-SD cards hurtling > > down the highway? > > $BIGNUM. I did see an actual 1970s station wagon loaded with RL02 cartridges once, pulled up at the dock of Baker Systems, the large Computer Science building at Ohio State (I suspect they were cleaning out a machine room and someone wanted the packs. Obviously I didn't know the right person that day). At Pole, we saved all the raw sensor data from AMANDA and later Ice Cube to DLT-format tapes (increasing the media/drive density over time) once a year, and it quickly grew to the point that we were stuffing several hundred TB of tape into an LC-130 to ship back to Wisconsin. It took 3-4 months to read last year's data once it arrived. So maybe not a 747 full of magtape, but still, a couple of cubic meters of DLT tape going 850 miles in 3.5 hours (Pole to McMurdo) is pretty decent bandwidth. The MCM->NZ leg was on a jet (C-17) so it upped the bandwidth, but on a larger plane so the effective capacity utilization dropped. -ethan
[cctalk] Re: ST-251 Data Recovery for Glenside Color Computer Club (GCCC)
On Tue, May 16, 2023 at 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... < > 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. I have an MDM Emulator and it's nice, on those occasions you are trying to read a supported drive (it supports a _lot_ of encodings, but not every single platform). Two layers - fortunately in this case, the low-level format is known (WD1002A-WX1) and that's good. I'd totally expect an MFM Emulator to be able to pull bytes off the drive. I am not a CoCo person so I have no idea what tools can be used to pull files from a raw pile of disk blocks there. -ethan
[cctalk] Re: DEC RL device
On Sun, Apr 30, 2023 at 8:47 PM W2HX via cctalk wrote: > Can anyone tell me what I picked up at a NH hamfest this weekend for $20? I > see it says RL01/RL02. I have two RL02 drives and some platters. None of > which I have gotten around to trying. Other than a copious amount of pine > needles, what can this be used for? Or maybe the right question is, should I > not use it for fear of destroying an RL platter? > > https://w2hx.com/?prefix=x/VintageComp/Platter-Device/ Wow! Pretty neat - looks like a pack inspector for RK05, RL01/02, and RK06/07 based on the (blurry) instructions. Runout, at least, and certainly a few other measurements - would probably identify a pack that had been dropped hard enough to bend something (before you stuff it in a drive and ruin both). It doesn't look like a cleaner - I've seen an RK05 cleaner and it's a bit different - more about running a Texpad over the surface while slowly rotating than measuring anything. Cool find! -ethan
[cctalk] Re: mainframe vs mini
On Thu, Mar 9, 2023 at 5:05 PM Cameron Kaiser via cctalk wrote: > This has been around the block: > > You can lose a screw in a micro. > You can lose a screwdriver in a mini. > You can get lost in a mainframe. We had an Amdahl in the middle of a multi-thousand-square-foot computer room (one of several) at work 25 years ago. I do not know/remember the model number but it was made of up several cabinets not in a line. It had such a convoluted layout that you could literally stand in the "middle" of it and not see outside. If you stood in exactly the right spot, the blank panels lined up and made the visual appearance of a box with no exits. You _could_ get lost in that one, as long as you didn't take half a step away. -ethan
[cctalk] Re: on the origin of home computers
On Wed, Mar 8, 2023 at 3:59 PM Bill Gunshannon via cctalk wrote: > I had some good sized iron in my home in the early 80's. We (my family - I put up 1/3, my mother covered the other 2/3) got a PET in 1979. I came home from my first Dayton Hamvention in 1982 with a PDP-8. If a high school kid can scrounge a PDP-8 by the early 80s, I'm sure an adult with a real job could have done it a lot earlier. -ethan P.S. - 90% of what ran on that PET was games - commercial ones bought from Creative Computing and Instant Software and others, as well as lots of games typed in from books and magazines (Creative Computing, BYTE, Micro, etc). We didn't have a printer and the only storage was cassette tape, so word processing and other "serious" applications were off the table. I did have some utility firmware - an improved machine language monitor (NMON), which I used to write better games (hand port of Scott Adams' engine from BASIC to 6502 machine code), BASIC Toolkit, and BASIC Aid, used for writing better programs in BASIC. Yes, Bill, arcade games were better, but they cost $0.25 a play and I could play what games we had for hours on the PET. We didn't have an Atari or other home video game console. I also typed in and played several text adventures, something that was not available on a console or in an arcade. I'm not saying that nobody did "engineering work" on a home computer, but by 1980, we sure were playing a lot of games on home computers.
[cctalk] Re: Computer of Thesus
On Mon, Jan 23, 2023 at 6:09 PM Sellam Abraham via cctalk wrote: > I submit that the //gs isn't even really an Apple ][ properly. > It's more like a quasi-Macintosh with really good (not perfect) built-in > emulation of an Enhanced //e. That totally makes sense. I never got into the //gs and that kind of frames it: I'd rather just use a //e (which is still late for me) or a ][+ but that's because I first used them back in the Integer BASIC days (and watched friends do the DOS 3.2->3.3 conversion) then used them heavily in 1984. It's just where my experience falls. -ethan > Sellam
[cctalk] Re: [SPAM] Re: what is on topic?
On Sun, Jan 8, 2023 at 11:52 AM Liam Proven via cctalk wrote: > > Win95/Win98 would be happy with a PC/AT 286, with appropriate RAM > > Nope. 32-bit only. 386DX or later. I tried it and benchmarked it at > the time of release. And it beat WfWg 3.11 by a significant margin, to > everyone's amazement. I have a memory of installing Windows 95 on a monochrome 386SX laptop w/4MB of RAM in August, 1995 at McMurdo because that's the equipment we had on hand when Win95 arrived on the continent. It was unpleasantly slow but it did run. Way better on a 486 w/8MB. -ethan
[cctalk] Re: Diablo series 30 or Dec RK03
On Sun, Jan 8, 2023 at 1:50 PM Chris Zach via cctalk wrote: > That will be complex. I had an RK8 disk controller (the 6 foot cabinet > that was it) along with a pair of the RK03 disk drives and it was (a) > insane, (b) heavy beyond belief, and (c) finicky. I think I've only ever seen pictures. I know I haven't seen one up close. > It also required Data break which is not built into the stock pdp8/L. That's just a few common modules, fortunately. > You would need a BM08 box, and as I'm looking for one myself they will > be tough to get :-) Absolutely. Not a lot of benefit having storage without memory extension. > You might be better off getting your 8/L working and trying things like > FOCAL on paper tape and other simple paper tape/serial based stuff. > Running OS/8 will require either a pdp8/I (with the extra memory, data > break, and helpful things like the EAE) or as I mentioned a BM08. FOCAL is absolutely a good starting point for making a 4K PDP-8/L do _something_ interesting. I haven't ever tried doing assembly using the paper tape tools (it's several passes and uses quite a bit of tape) but I have assembled small programs by hand and toggled them directly into the front panel. Obviously that's no fun for anything over a few dozen instructions. -ethan
[cctalk] Re: Diablo series 30 or Dec RK03
On Sun, Jan 8, 2023 at 6:40 AM jos via cctalk wrote: > On 08.01.23 01:51, jake utley via cctalk wrote: > > Hello everyone I’m a young collector (18) of 60s and 70s minicomputers and > > micros. I have been restoring a PDP-8L and would love to find ether a > > Diablo series 30 or Dec RK03 removable cartridge drive to go with this > > system. > > Is it even possible to add a diskdrive to a PDP8/L ? My 1970 "Small computer > handbook" only mentions TU55/TC01 and DF32 as mass-storage options for the > 8/L. Both are essentially unobtainable. Indeed. I have had a PDP-8/L since I was in High School (eons ago). I have never come up with mass storage for mine and it's long been a goal to be able to do more than paper tape programs on it. Dry so far. Posibus storage devices were, IME, less common than Negibus devices (which would then require a DW08 and by the time you bought all of that, why didn't you get a PDP-8-i in the first place? (especially since you were memory-limited on the -8/L) > Maybe sell the 8/L and get yourself an 8/E or /F ? Much more flexible. I do get wanting to max out an 8/L. It was my first and I'd love to get it doing more things, and it's really cool that you can easily see what's happening at the gate level (possible but less convenient with an Omnibus machine), but there's only so much you can do with _any_ 4K PDP-8, and memory expansion boxes for the 8/L may be rarer than Posibus storage devices. It's a lot easier to bring an Omnibus machine up to 32K and there are lots of vintage storage options. Recreating these things with modern components is always a possibility, of course, but I've only ever seen a couple of one-off devices ever come out (like a Posibus DF32D emulator implemented in TTL that happens to need a now-hard-to-find 128Kx16 NVRAM) Personally I'd love to see some Posibus devices get recreated but after this long, I'm totally willing to see if I could get SerialDisk working with an add-on serial port on an -8/L or unexpanded -8/i. My own (perpetual) goal is to run OS/8 on a pre-Omnibus machine. Haven't pulled all the resources together for that yet. -ethan
[cctalk] Re: what is on topic?
On Tue, Dec 20, 2022 at 5:35 PM Bill Degnan via cctalk wrote: > We used to shun anything newer than and including the IBM PC but > time.marches on. You're safe if you discuss systems produced before 1990. > After that put an OT in the front of your subject so as not to offend the > purists. Personally I think anything built after 1995 is too new for > cctalk, but thats just me. As mentioned elsewhere, the old "10 year" rule is long irrelevant. I think 1995 is a good general cut-off for a strictly time-based threshold, but it's not a hard boundary - PPC Macs I would think should still be in bounds. A softer rule would probably be "(nearly) anything goes except nearly-current Windows PCs". If a machine can run WinXP, it's too new. Also as mentioned, there are plenty of lists about modern PCs. -ethan
[cctalk] Re: Inline Serial Device?
On Sat, Nov 12, 2022 at 8:23 PM Sellam Abraham via cctalk wrote: > I recommend the DEADBEEF dish. FEED FACE DEAD BEEF -ethan
[cctalk] Re: Inline Serial Device?
On Sat, Nov 12, 2022 at 12:18 PM Chuck Guzis via cctalk wrote: > On 11/12/22 02:28, Tony Duell via cctalk wrote: > > ... This is the sort of > > thing I'd do with a couple of transistors or an NE555 depending on > > which turned up in the junk box first. > > One thing that a small MCU has over a 555 is that it can be programmed > once and you can be assured of its frequency stability. No fooling with > pots and caps to get the thing to work the way you'd like. Yes, that, plus since many products have a hardware team and a firmware/software team, the hardware can be designed to general requirements and sent out for manufacture while the software team has time to write the firmware (and make changes long after the hardware is set). One of the first times I encountered this was stripping some old emergency exit lights for parts c. 2008. The switching supply had an 8-pin PIC for the oscillator instead of a 555. Yes, a 555 could have done it, but the PIC didn't need any external components to set the frequency, components that can drift with age, and components that take up board space. Even if the 555 and MCU were identical in cost for the IC, the MCU was cheaper because of the smaller footprint. Additionally, the designers had some flexibility. To change the frequency with a 555 after manufacture is an expensive proposition. With an MCU, if it's flashable in-circuit (clip or possibly programming pads near/at the MCU), then one can change the behavior without melting any metal or purchasing components. While one may never need to change the frequency of a SMPSU oscillator after initial design, there are plenty of products where it's handy that the hardware guys can say "here's an output that can go from 1/10Hz to 20Khz - what do you want it to be?" and not worry about design limitations, just set the frequency in the firmware and it does that. You can build some generic hardware (X inputs, Y outputs with Z mA current drive) and fine tune things later, or have variations on what the inputs mean and not have to change the PCB. Yeah, the 555 is extremely simple and is well known and is fairly cheap, simple MCUs are simple (and cheap) even if they aren't 100% deterministic like a chip with 20-30 transistors. There's economic advantage in flexibility. -ethan
[cctalk] Re: 14 DZ11's for sale/whatever
On Tue, Nov 1, 2022 at 12:01 PM Paul Koning via cctalk wrote: > > On Oct 30, 2022, at 2:49 PM, Wayne S via cctalk > > wrote: > > > > The difference between dz and dh interfaces is that the dh used dma instead > > of interrupts to get characters to the cpu... > > No, it doesn't. I was confused about this but was recently corrected. > > The DH11 does DMA output, but not DMA input. I don't know any DEC serial > port devices that have DMA input; it would make very little sense to do that > since input generally is one character at a time. Yes. I was going to mention this in my previous reply but got sidetracked. The big benefit for DH11 and DMF32 and 3rd-party DH11 work-alikes (Emulex CS-21...) is that since under normal workflow, many times more chars go out than come in so DMA-out saves a lot of overhead when blasting screens of stuff (like refreshing your page in EDT...) and people don't type all that fast by comparison. Where we used to have problems is having multiple Kermit sessions on our serial ports. Those hammer both ways. Fortunately, I wasn't trying to support PDP-11s with split baud rates like 1200/150 that were used to _really_ reduce input interrupt frequency. Our machines kept up at 9600/9600. -ethan
[cctalk] Re: 14 DZ11's for sale/whatever
On Sun, Oct 30, 2022 at 2:49 PM Wayne S via cctalk wrote: > The difference between dz and dh interfaces is that the dh used dma instead > of interrupts to get characters to the cpu. It would be transparent to any > software. > I did a write up on them 40 years ago justifying the replacement of a dz with > dh saying that decreasing interrupts would increase performance on my VAX > 780. It did, but just a bit. To make a big difference, you’d have to have a > LOT of people banging away on serial terminals and rs-232 connected printers. When I ran Unibus VAXen in the 80s every day at work, our small machines had 5-9 serial ports for 1-4 users and our largest machine had 57 serial ports (multiple Emulex CS/21 and at least one DEC DMF32 plus the console) and several dozen users. We never moved to terminal servers or other external connection management. It was all individual serial connections routed to offices and workrooms. I think our peak usage was 50-60 active users but at that point, the 8MB of physical memory started to be a constraint. I don't think the 11/750 could have handled that many users on DZ-11s. -ethan
[cctalk] Re: PDP 8a front panel hardware
On Wed, Oct 12, 2022 at 11:36 AM Paul Koning wrote: > > The clip nut is 10-32... > > That's the same clip nut used on H-960 racks. I saw some at the local > hardware store recently. An unusually well stocked hardware store, > admittedly, but clearly they are still current items. It's the same threading but not the same style. The H960 clip nuts I have a real "nut" wrapped in a thin metal frame that wraps around the rail. This clip nut is a bit of plate steel with a machined and threaded "dimple" in the middle, and a small tang to latch into a thin metal carrier that looks spot welded to the bracket. You could probably use a rack clip nut in this application but I think the hole in the bracket would have to be a tad larger for a standard clip nut to engage, and then the cast metal front panel would be resting on the face of that clip nut clip instead of directly on the metal bracket with this design. It would probably affect a tight seat, and might lead to scoring on the inner face of the casting. Probably wouldn't matter much in practice, but a design and UX engineer might not like the difference. -ethan
[cctalk] Re: PDP 8a front panel hardware
On Tue, Oct 11, 2022 at 7:21 PM Vincent Slyngstad via cctalk wrote: > Bob Armstrong sent some pictures from Jack, which helped my find the > photos I knew were online somewhere: > https://forum.vcfed.org/index.php?threads/adding-a-programmers-console-to-a-pdp-8-a.75942/#post-921828 That's exactly what I have. -ethan
[cctalk] Re: PDP 8a front panel hardware
On Tue, Oct 11, 2022 at 1:17 PM Vincent Slyngstad via cctalk wrote: > On 10/11/2022 10:08 AM, Tony Duell wrote: > > On Tue, Oct 11, 2022 at 6:04 PM Vincent Slyngstad via cctalk > > wrote: > > > >> Those are the ones. The 3D printed parts are essentially triangular > >> blocks that mount to the rack and have a drilled and tapped hole for the > >> recessed Allen screw. As a 3D Printed part, looks good. > > Why on earth would you 3D print something like that? Machining it from > > a metal block would be a lot stronger. Strength isn't the only parameter here. A plastic block is plenty strong enough unless you routinely pull down on your front panel when you are standing up. I _am_ a fan of small machine shops, but even though I have access to a very nice one at our Makerspace, it doesn't take me that long to download a part file and press "print". > The DEC part is essentially bent bar stock, with a nut press-fit into > it. Also easy to to do if you have the tooling. Yep. I have mine right here. My micrometer is elsewhere, but looks like it's made from 1/8" steel flat stock (with anti-corrosion plating), and has 3 bends (apex and two ends), a clip-nut for the machine screw in the cast face, and two mounting holes. Not hard to make with a mill (or a file) and a break. The clip nut is 10-32, BTW. I just checked. No more difficult to source tooling than 6-32 If you made it from metal. you could skip the clip nut and tap the bracket itself, but if you removed the face often, I could see that eventually stripping-out. > I know a lot more folks with a 3D printer than I do the folks with metalwork > experience. Agreed. I know lots of people with 3D Printers that cost $300 USD or less, and they are much easier to learn to use than learning how to run a mill (safely). There's absolutely nothing about this part that you couldn't make on a 10-year-old tiny hobby 3D Printer. It's not detailed and can easily be made from ABS or PLA (the most common plastics). If you printed it on its side (with the notch facing "up"), with unbroken filament going around the perimeter, it would be a lot stronger than printing it "point up" in layers. Your mounting holes might be a little more ragged but they are covered up anyway. I haven't printed Vince's parts but on the surface, they look good. One possible improvement could be to design in a pocket for a 10-32 nut. There are ways to print parts and pause the printing to install metal hardware and overprint for retention. It's not a beginner's technique, and heat-staked inserts are easier to apply, but a captured nut can be made to float. -ethan
[cctalk] Re: Data Systems Designs floppy interface cross-compatibility?
On Sun, Sep 18, 2022 at 2:30 AM jim stephens via cctalk wrote: > I'm getting ready to move to KC and my pile of DSD is back there. Hi, Jim, Cool. > I have both PDP8 varieties and PDP11. One complete system from Sellam > which hopefully contain data, etc. Dual booted for a friend he helped > maintain it. I have boxes of floppies that were the residue from a rescue in Champaign where Jack Rubin (who was closer) got first pick, and I got the things he didn't want/didn't fit in his car. From the directory slips and markings on the box, I suspect many of these floppies are double-sided and were used on DSD drives. Mix of PDP-8 and PDP-11 contents. > A guy in West Wendove NV had a number of subsystems and > I have all of them. We'll have to make a date to do a prisoner > exchange, and I'll loan / trade you what I've got, and hopefully come up with > working systems. Sounds like a plan. I'm not in a massive hurry, I just wanted to see if I had all the parts on hand to do _something_ > I've got two of the units with the SA-1000 drives as well. I've read the docs but haven't seen those in person. Kind of handy for a smallish PDP-11 setup. > Will take a bit of sorting, will have it on the list to get some stuff and > visit you later this year, but probably next year. Since it's already late September, I will just expect next year, but if something on your end changes, just say the word. I do have some "blackout dates" for various weekends through the end of the year - travel between here and NYC or here and Chicago, etc. > Glad you're looking into this. I don't think I've got enough > to run much on DEC disk hardware. I have an abundance of PDP-11 and PDP-8 gear. I'm trying to see what (still) works and fix what does not. So far, I have been entirely unable to even so much as read an 8" DEC floppy this year. I keep taking different stabs at it. Part of the problem is that I have mostly older (70s/80s) gear and the newer stuff (90s) doesn't work with old peripherals. Case in point, my DSD 8838 card has written in sharpie on the bag "does not work with PDP-11/73". That's not unusual. There are a lot of older Qbus cards that don't work with "MicroPDP systems" (usually meaning J-11). > I think among a pile of 8/As I got from sellam there are > DSD cards, but it was all unsorted. Hand over money load and drive > with a pile is the state of that lot. Right. > I have makings of 6 or 8 8/A's would like a couple, but DSD again > would be nice. I have three hex-wide Omnibus boxes, I'd like to keep 2 and sell 1 to someone, and I have two quad-wide Omnibus boxes -8/e and -8m) and I may want to get both of them running. I have an assortment of drives and peripheral cards, enough to load up all the machines, if they are all functional. Where the DSD drive comes into play is that it can format RX01 media (I have boxes of blank-blanks for CP/M machines) and mine (DSD480) can do double-sided media, which is only important to me for reading double-sided media. I wouldn't want to depend on a working double-sided drive for an operational setup. For real DEC drives, I have a number of RX01 and RX02 drive units and a box of spare parts (motors, belts, door latches, etc). Let me know when any of your plans crystalize. Most of my travel plans involve events like VCF so I can't haul lots of things because I already have a load of event-related materials. I also don't usually get out past Chicago going West. I haven't driven to St. Louis in well over 20 years. -ethan
[cctalk] Data Systems Designs floppy interface cross-compatibility?
Greetings, all, While getting ready for VCF Midwest etc, I have been spending a lot of hobby time in the past year digging out various DEC minicomputer items and testing/repairing them. To that end, I've been staring at a DSD480 on top of a PDP-8 rack. It's one of the ones with the DSD 26-pin interface. My question is that since there are several different devices with that connector, are any of them compatible with each other? Specifically, here are the DSD interfaces with a 26-pin connector: 802130 DSD210 PDP-11 Interface (26 pin) (2130) 802131 DSD440 DSD210 PDP-8 Interface (26 pin) (2131) 802132 DSD210 LSI-11 Interface (26 pin) (2132) 804430 DSD440 PDP-11 PDP-11 Interface (26 pin) (4430) 804432 DSD440 LSI-11 LSI-11 Interface (26 pin) (4432) 808830 DSD880 (SA850/SA1004) PDP11 Interface Card (26 pin) (8830) 808832 DSD880 (SA850/SA1004) LSI-11 Interface Card (26 pin) (8832) 808836 DSD880/20/30 (SA850/Q240) LSI-11 Interface Card (26 pin) (8836) It looks like the 2131 board is Omnibus and works with either the DSD440 or DSD210, but on the PDP-11, can the 883x interfaces work with older drives or do they only work with the DSD880 floppy/hard drive box? I remember where/when I got this DSD480, so it seems likely to me that I have a PDP-11/34 with an 4430 board in it. I could probably use an 2131 board just so I have an Omnibus interface. I also have an 808836 board but do _not_ have a DSD880. I've found the prints on bitsavers that cover the DSD440/480 interface so I know what signals are there, but I haven't found the equivalent docs for the DSS880, just user guides. Anyone here know enough about DSD products to shed some light? Thanks, -ethan
[cctalk] Re: Test Message
I see it (and I observed the same thing - just rejoined after having subscription problems stretching back to May, and didn't see any traffic). -ethan On Fri, Sep 16, 2022 at 12:09 PM Kevin McQuiggin via cctalk wrote: > > Pardon the test message, I have just re-subscribed to the list but have seen > no traffic on it for a couple of days. > > Kevin McQuiggin
Re: Possibly going up to VCF, stuff I would like to sell/get to proper people pdp8/12/HP stuff
On Mon, Apr 11, 2022 at 8:43 AM Chris Zach wrote: > On 4/10/2022 6:05 PM, Ethan Dicks wrote: > >> Ton of pdp8/12 IO cables. These are the black circular wire ones, I > >> think negibus. > > > > There's definitely some discussion going on about those. They are > > desired by 12-bit folks. > > *nod* To me classic computer stuff falls into two categories. There is > stuff that is common so you sell it for a reasonable price or trade it > or whatnot on Ebay/whatever. Q bus boards, systems, normal pdp11's, > stuff like that. You just either sell it on Ebay (whatever) or give it > to someone for a minimal cost of shipping and handling who has a system > and really needs it (think 11/24 CPU boards) Sure. > Then there is the stuff that is "priceless" and goes for stupid amounts... Agreed. > The IO cables fall into the latter category. So what's the best way to > have them find a home with a person who will use them and not just > another trophy in a box of parts or an exhibit in some museum? Thunderdome? ;-) But seriously, probably to ask here and on the Classic Computer Discord channel (a mix of folks from here and not from here, mostly US-based) who could even use such a thing. I have a couple of Negibus machines. The only one I'm really missing cables for is a PDP-8/S, so I can connect up a PT08 once I find/fabricate one. If someone had a PDP-12 or LINC-8, that would be, to me, a higher priority need (especially since I haven't even relamped my -8/S yet). I wish I'd gotten the ASR-33 that originally came with it (since some had the PT08 in the base) but alas, that was gone before I got there. Events like VCF concentrate the interested population - I've been part of a "12-bit panel", up on stage with Kyle Owen, Jack Rubin, Vince Slyngstad, etc., exactly the sort of people who would _use_ I/O cables not flip them. Trade stuff is harder. I know you are seeking external memory boxes for the -8/L, but those are quite rare. I just have the one and it's not an extra. Any 12-bit spare parts I might have are Omnibus bits. Cheers, -ethan
Re: Possibly going up to VCF, stuff I would like to sell/get to proper people pdp8/12/HP stuff
On Sat, Apr 9, 2022 at 3:43 PM Chris Zach via cctalk wrote: > I'm thinking about going up to VCF in Wall next weekend. 22-24 Apr, as mentioned... I should be there too. > I haven't been > to it since it was the Trenton Computer Fest (think late 1990's) Totally unrelated event. > so I'm > not sure what the protocol is on tailgating, trading stuff or whatnot. > Appears that they have a "sale room" you drop things off in with prices. > Ok Yes. There's a "consignment room" and you leave your stuff with labels and prices and there are volunteers staffing it to collect money and record sales, etc. There's a house cut (but I am unsure how much it is so I don't want to just guess). > Stuff I could bring to get out of my house and into the right hands: > > Big box of pdp12 schematics. This came from my olden days when I had to > turn up a pdp12 because it will not fit in a station wagon. Still it > looks like board locations and a lot of 12 stuff. Big box, heavy to > ship, easier to drive over. > > Ton of pdp8/12 IO cables. These are the black circular wire ones, I > think negibus. There's definitely some discussion going on about those. They are desired by 12-bit folks. -ethan
Re: DEC H500 Digital Computer Lab
On Fri, Mar 11, 2022 at 8:03 AM Tom Hunter via cctalk wrote: > As there is no real cctalk traffic other than test messages I thought I > post something a bit more interesting. Here is a short video of my fully > restored DEC H500 Computer Lab with an 8-bit counter implementation > including reset: Hi, Tom, Great post and timely. I recently got leads for my H-500 but I didn't get exactly "one set". I know I didn't get any of the longest wires but I also got a couple extra, I think, brown ones for the tips. I read through the handbooks and the closest thing I found was page 173 in the Workbook that mentions "Bundle of Taper-Pin Patchcords (107 of Assorted Lengths), Model Number 916, $30). Could you post how many of each color you have? It's possible, of course, that you don't have exactly "one set" either, but if you happen to have 107 wires, that's a good indication, especially if your tally matches mine anywhere. Here's what I have: 22 BRN ~ 3" ( 2-7/8") 30 RED ~ 5" ( 4-7/8") 25 ORN ~ 7" ( 6-7/8") 20 YEL ~ 9" ( 8-7/8") 10 GRN ~17" (16-7/8") 0 BLU - 107 -ethan
Re: 11/83 operating system load update -2
On Tue, Feb 22, 2022 at 9:29 PM Rod Smallwood via cctalk wrote: > 2. The PC I want to use is a DEC Celeibris FX ie the PC and its W95 > software is as supplied by DEC. . . . > 5. putR was supposed to be able to do this. It does not. Rod, My memory is that programs like putr need to run on "real" DOS, not a DOS window. So if you are trying to run putr without booting to MS-DOS 6.2 or older, that could be the source of your problems with it. > 6. All that is lacking is the right utility. I think other utilities (Teledisk, ImageDisk, etc) _also_ require MS-DOS not a DOS window under Windows. -ethan
Re: Installing an operating system on the 11/83 - update.
On Tue, Feb 22, 2022 at 10:43 PM Jay Jaeger via cctalk wrote: > Writing a 360KB or RX50 diskette with a 1.2MB drive is a path to a lot > of frustration. Not only do you have to double step the drive (software > often takes care of that part), but the tracks written will be narrower > than a real RX50 / 306KB drive... A real RX50 is an 80-track drive. You are correct that writing a "360K" floppy on a high-density drive is not a good idea, but a real RX50 _is_ 80 tracks, just single-sided, for a total of 400KB per disk. The RX50 drive itself has one rotation motor and one positioner motor but the heads face outward from the middle, one head per disk. The hub is a strange split affair where the top rotates the opposite direction from the bottom (and is driven by a belt in the middle). A somewhat unique arrangement in the peripheral arena. -ethan
Re: Installing an operating system on an 11/83
On Tue, Feb 22, 2022 at 10:20 AM Antonio Carlini via cctalk wrote: > I imagine it was possible to hook up RX50s to a VAX-11/750 but I never > saw one configured that way. Why not use tape :-) We had an RUX50 on our 11/750 (I still have it). It's just another MSCP controller, but since we had a UDA50, our RUX50 was configured at an alternate address. I suppose we could have booted off of it, but we would have needed a bootstrap that could boot from a non-primary controller. Our boot ROMs only knew how to boot device 0 on the primary controller. -ethan
Re: Installing an operating system on an 11/83
On Tue, Feb 22, 2022 at 9:02 AM Antonio Carlini via cctalk wrote: > I never installed it this way myself, but MicroVMS on the MicroVAX II > was distributed on RX50 floppies: lost of them. I have 2-3 install kits for MicroVMS on RX50. I'm working on imaging them. First attempts were not successful (media is fine). I will have to re-try this Spring. Each one is a large stack of floppies. Multiple savesets with up to a dozen disks in each (but mostly 1 to 4 per saveset is more common. -ethan
Re: Is The M9312 Boot Module Essential?
On Sat, Feb 19, 2022 at 4:40 PM Fritz Mueller via cctalk wrote: > > On Feb 19, 2022, at 12:11 PM, Fritz Mueller wrote: > A few additional details, in case it is helpful: > > IIRC, the 11/34 doesn’t have SACK timeout implemented in the CPU cards (the > /34A did add this, however.) So without an M9302 on the far end of the bus, > the CPU could hang in a situation with an unacknowledged grant (which I think > would be somewhat rare, but possible). I believe it is possible to boot an > 11/34 at least as far as a ROM boot monitor with a non-SACK (M930 or such) > terminator on the far side. Thank you for bringing this up - I have a stack of KD11-E and KD11-EA board sets (and MOS memory and all the other things). I've been trying to get them to work in a BA11-L that started off life as a PDP-11/04 and I've swapped the DD11-DK for a DD11-P backplane but I wasn't having any luck getting things to run. I did find a bad 7402 in the limited function front panel but that was the only fault I found (so far). I've checked the grant chain but what I haven't done is ensure I have the right combo of terminators and CPU cards. I'm used to configuring machines, but I honestly forget if the experiences I had in the 80s were 11/34 or 11/34A. This gives me something to go back and check. I was about ready to start hacking on an M9302 to sniff out the SACK logic. Now I'll go back and check the docs and make sure I'm putting together a set of cards that's going to want to play nice with each other. I have plenty of dual-height grant cards. I'm definitely _not_ having issues with NPR. Thanks! -ethan
Re: Retro Chip Tester Pro, done!
On Mon, Feb 7, 2022 at 8:32 PM William Sudbrink via cctalk wrote: > You may recall that, a few weeks ago, I requested parts help (shopping > baskets) for the Retro Chip Tester Pro that I got for Christmas. Well, > today's mail > brought the last few parts and I have finished and tested it. Cool. Good to see it. I have a board I need to populate myself (mostly I need the MOSFETs) -ethan
Re: 8" Floppy Drives needed
On Wed, Jan 12, 2022 at 12:16 PM Mike Katz via cctalk wrote: > I am looking for one or two 8" floppy drives, preferably Shugart > compatible at a reasonable price. > > Does anyone have anything like this laying around, unused, in their > basement, storage locker, garage, etc. > > I am looking to make a RX01 (and hopefully RX02) disk formatter and copier. Mike gets first choice, of course, but I'm also looking for something similar, especially since doubled-sided half-height drives (TM848) can become media strippers (two ceramic heads vs one head and a pad). I just need to read single-sided DEC media, so that's fine. I should have all the cables and adapters and such squared away shortly, and I already have a 486 I'm using with ImageDisk, TeleDisk, and PUTR with 5.25" media. 8" is next, especially a large carton of RX01 media. RX02 might have to wait on getting/finding an RXV21 and restoring an RX02 because the format is oddball. I think I have an RXV21 somewhere but I wouldn't have used it in this century. After Mike gets squared away, I'm in for a SS FH 8" drive. I'm in Ohio. -ethan
Re: VAX 780 on eBay
On Mon, Jan 3, 2022 at 12:29 PM Bill Gunshannon via cctalk wrote: > On 1/3/22 11:50 AM, Ethan Dicks via cctalk wrote: > > I'll agree with that. We used to run 40-50 users on our 8MB 11/750 > > (with both CMI and Unibus disk) but it did do some swapping over 8-10 > > users. > > You obviously didn't use the Ada compiler. :-) > > Or Eunice, for that matter. Hell no! 90% of our work was in C, the rest in m68k assembler (our own), VAX MACRO, or FORTRAN. We started off with Whitesmith's C then by the late 80s also used DEC's VAX C. Compiling all the code for our product took the 11/750 6 hours to compile and link plus an additional 2 hours for an 11/730 to link under a different version of VMS. 8 hours total to rebuild totally from source. Some things about the good old days weren't so good. -ethan
Re: VAX 780 on eBay
On Mon, Jan 3, 2022 at 12:18 AM Warner Losh via cctalk wrote: > I had accounts on a MicroVAX 2 and a VAX 11/750. The microvax was faster > for most compute jobs, but the 750 with 1/4 the memory handled more users > mostly in text editors with the occasional compile or nroff/troff jobs. > IIRC, the 750 had faster disks... I'll agree with that. We used to run 40-50 users on our 8MB 11/750 (with both CMI and Unibus disk) but it did do some swapping over 8-10 users. The MicroVAX II was a pretty snappy single-user machine, but was a big sluggish over 4 users. Our big compute jobs were running compilers. Most of our user load was VMS MAIL, EDT, MASS-11... -ethan
Re: VAX 780 on eBay
On Sun, Jan 2, 2022 at 11:31 PM Chris Zach via cctalk wrote: > Oh yes, the 730 is probably the neatest little "pocket Vax". Especially > if you have the R80 drive as well as the RL02. The R80 did not use the > Unibus, correct? Correct. The R80 connects to the RB730 controller which has its own slot at the top of the backplane. My first UNIX install was on an 11/730. I ran a Usenet node (k-panda) for a couple of years on it. -ethan
Re: What is a BC01-R
On Sat, Jan 1, 2022 at 6:40 PM Chris Zach via cctalk wrote: > Regardless, I found a M857 board with a RS232 cable on it and BC01R-25 > on it. Was that for a pdp11/05 by chance? I found this reference from the Cables Handbook. Sounds like it was a generic cable that probably worked with several devices. http://www.pdp8online.com/bklatt/43.jpg My recollection was that the PDP-11/05 had a special 40-pin Berg connector off the backplane for the integrated Console SLU. -ethan
Re: TU56 DECtape takeup reel needed
On Fri, Dec 17, 2021 at 10:13 AM Paul Koning via cctalk wrote: > > Has anyone tried 3D printing these? > > Interesting idea. A while ago someone posted a picture of what looks like a > "go/no-go" gauge for DECtape reels. It is marked with the dimensions of the > two sides: 2.504-2.505 inches for the "no-go" end, 2.494-2.495 for the "go" > end. So that tells us the hole diameter is 2.500 +/- .004. Can 3D printing > deliver that sort of tolerance (with hobbyist-price machines)? What you can do is print with extra shells (2 layers is one default, depending on your slicer), then print using ABS, which will shrink 1-2% (so you often print at 100.1% and caliper for dimensionally-critical items) _then_ since it's ABS, you can vapor-smooth with acetone and remove ridges and improve top layer bonding, *then* turn on a lathe to spec - but trying to remove less than half a filament diameter. I think that technique would work. I wouldn't just print and go unless I at least smoothed the tape path to prevent adding wrinkles. -ethan
Re: Wanted: IBM PC compatible 8 or 16 bit Arcnet cards
On Mon, Dec 13, 2021 at 5:06 PM Mike Katz via cctalk wrote: > For my kids and their friends I used to set up several (up to like 5) > bare motherboards first with lantastic 2MB cards and then NE2000 10mB > compatible cards and play Doom over IPX back in the 90's. Yes. Thank you. IPX. That was the network layer. -ethan
Re: Wanted: IBM PC compatible 8 or 16 bit Arcnet cards
On Mon, Dec 13, 2021 at 3:09 PM Grant Taylor via cctalk wrote: > On 12/12/21 10:28 PM, Ethan Dicks via cctalk wrote: > > I haven't used ARCnet since we used to use it for 4-player Doom > > (especially since not everyone in the gaming group had Ethernet at > > home yet and it was easy to make a passive 4-port ARCnet hub. > > I find this statement interesting for a couple of different reasons: > > 1) Paying Doom over ARCnet. -- I don't think I realized that ARCnet > was standardized enough that normal networking applications would work > over it. -- Naivety on my part. The Doom application contained a network stack that would handle the higher layers. IIRC, you still had to load a packet driver shim, but perhaps not. It's been a lng time since I've done it. But you definitely could play up to 4 players when each machine had an ARCnet card. Ethernet cards worked too but they cost a lot more at the time. > 2) "it was easy to make a passive 4-port ARCnet hub" ... I don't know > how to respond to that with anything but curiosity and /many/ open ended > questions. https://apenwarr.ca/arcnet/howto/cabling.html You just take 4 BNCs and 4 resistors. Tie all the grounds together (can use a metal bar or wire or whatever) and connect one resistor to each core and tie all 4 resistors together. In other words, ARCnet supports a Star topology that Ethernet does not. It's a token-passing scheme, not CSMA (collision detection). Cheers, -ethan > > > > -- > Grant. . . . > unix || die
Re: Wanted: IBM PC compatible 8 or 16 bit Arcnet cards
On Sun, Dec 12, 2021 at 4:27 PM Jonathan Haddox via cctalk wrote: > I'll be following your progress with interest, I just installed Coax into > the walls of my computer playhouse so I can ARCNet with my S-100 system. I > have an ARCNet packet sniffer that can be loaned out if you would find it > helpful. > > Date: Sat, 11 Dec 2021 20:00:57 -0800 > From: Michael Brutman > > ... I've gotten to the point where I just want to have an Arcnet in > the house. I haven't used ARCnet since we used to use it for 4-player Doom (especially since not everyone in the gaming group had Ethernet at home yet and it was easy to make a passive 4-port ARCnet hub. -ethan
Re: Cheap PDP-8 boards on eBait
On Sat, Dec 11, 2021 at 4:31 PM Ethan Dicks wrote: > On Sat, Dec 11, 2021 at 1:21 PM Noel Chiappa via cctalk > > https://www.ebay.com/sch/m.html?_ssn=jariadkin-0&_sop=10 > > > > has a couple of PDP-8 boards for sale that at the moment are going _really_ > > cheap. They went for $80-$100 each, not surprising really. Whoever the early bidder was came back at the end with a much higher bid. -ethan
Re: Cheap PDP-8 boards on eBait
On Sat, Dec 11, 2021 at 1:21 PM Noel Chiappa via cctalk wrote: > This guy: > > https://www.ebay.com/sch/m.html?_ssn=jariadkin-0&_sop=10 > > has a couple of PDP-8 boards for sale that at the moment are going _really_ > cheap. Tap handles and DEC boards? Odd mix. I took a risk and bid. I have an -8/e and -8/m to fix. Thanks! -ethan
Re: TU58 / DECtape II: Capstan goo
On Wed, Dec 8, 2021 at 2:43 AM Jos Dreesen via cctalk
wrote:
> >Also, when the tapes arrive, are there recommendations in case their
> > drive belts are gone?
>
> You can 3D-print replacements.
> Use Innoflex filament, 100% fill-in and the following OpenScad formula :
>
> module ring(d1,d2,w)
> {
> difference()
> { cylinder( w, d1/2, d1/2, $fn=230);
> cylinder( w, d2/2, d2/2, $fn=230);
> }
> }
> ring(38.2,35,6); // TU60 Dectape-II
Cool. Thanks for sharing that!
> Already 2 TU60 have been repaired with the above.
TU60 are direct-drive digital cassettes.
https://www.pdp-11.nl/peripherals/tape/tu60-info.html
The TU58 uses DC100 cartridges.
http://www.hp9825.com/html/dc100_tape.html
I had a boss who recycled some DEC TU58 for our HP 4951A serial
analyzer. It can format cassettes, the TU58 cannot, so it's a
one-way-trip.
-ethan
Re: RK11-C indicator panel inlays?
On Mon, Dec 6, 2021 at 5:28 PM Paul Koning wrote: > Raspberry Pico PIO engines are seriously cool. I used them to implement > DDCMP synchronous line protocol in a small USB device wrapped around one of > those devices. That includes the "integral mode" modulate/clock > recovery/demodulate functions. Ooh! That's neat. Sounds like it could also become a nice Bisync or SDLC serial adapter for IBM protocols (something from _my_ background) But it should probably get its own thread. ;-) -ethan
Re: RK11-C indicator panel inlays?
On Mon, Dec 6, 2021 at 10:36 AM Mike Katz via cctalk wrote: > One dumb suggestion to make it easier to control 144 lamps is to use > addressable LEDs. You can control them in banks or all in a single > serial line. If you use a single line you can control all of them with > just 1 GPIO. > > Each LED requires 24 bits of data. That would be 3,456 bits. The > WS2812B has a 300uS low start indication and 1.25 uS per bit. That > would mean it would take. 4.62mS to update the all of the LEDs. If 200Hz isn't fast enough for updates, and you have more GPIOs, you can implement this as, say, 4 strands and write out nybbles. There are cheap video wall that use MCUs with DMA engines and pump out 8 strips at once. > Since these are tri-color LEDs you can control the color and simulate > incandescent lamps Definitely > Another advantage to the LEDs is once they are set, you don't have to > talk to them again until you need to change something. Yep. Self-latching. > I am going to use a Raspberry Pi Pico RP2040 CPU's PIO co-processor to > drive the LEDS from a 432 byte array in memory. All I do is update > which LEDs I want to change and the PIO DMAs the entire array to the LED > chain once every 10mS (or slower depending on need). Sounds like a great approach. I have a couple of Picos but haven't dug into the PIO engines yet. I've been working with WS2812B LEDs for a while now and enjoyed watching the cost per LED plummet from a few years ago. -ethan
Reproduction DEC 144-lamp indicator panels (was Re: RK11-C indicator panel inlays?)
On Mon, Dec 6, 2021 at 9:42 AM David Bridgham via cctalk wrote: > The inlays are mostly not done with any tools I have. I do the graphics > with Inkscape. Rod made up the blanks with silk screening. Then I have > the white printing done at a printshop I found who has a large, flatbed > printer that can print white ink. I do have some ideas about how I > might try to make up blanks with a laser etcher I have access to but at > the moment we have an ample supply. Cool. > Also, I've experimented with making my own bezels out of PVC board from > Home Depot using a CNC router. In the pictures below, the yellowed > bezels are old DEC bezels while the white ones are ones I made. I > figured that if we ever get the QSIC shipping and people want indicator > panels (I hope they'll want indicator panels), I'd rather not depend on > them ripping apart old DEC bezels to make this work. Yes. I'd rather not demolish my only indicator panel. I was planning on demolishing a blank (I have a few short blanks, but most people do not) > Anyway, I'd be most happy to have another person with more tools to help > build bits and pieces of this stuff. I've noticed that as I gained > access to different tools, I came up with different ideas about how to > make things. I didn't think the laser etcher was all that useful until > I started using it. I have a small 40W laser etcher that I essentially haven't used since I have had access to large-format 80-120W laser cutters. As for tools, I can rent a 4'x8' Shopbot router at our local Makerspace that can turn out the light blocking bar or, from your file, the frame. We also have a local company (IC3D) that makes cubic-meter 3D Printers and makes their own filament from pellets, keeping costs down. The founders are friends of mine and I've helped repair sensors on their manufacturing line. If I had an STL, I could get a bid on what it would take to 3D print one. It wouldn't be as smooth as a machined PVC foam milled one, but it would be strong. With a little post processing, a 3D Printed frame may give an adequate look. Just a possibility. I haven't worked with PVC foam much but I understand the principle. > Now I want to use it for everything. Turns out it > can't quite handle 3/8" Delrin; it just melts it and makes a mess. That sounds like a power problem. Normally, Delrin lasers quite nicely, at least at 80W. Thick stuff is hard in any printer because of lenses, beam diffusion, etc. We sometimes have problems with 1/2" material of any kind in ours. I've done some stuff in 2 passes, one high, one low (refocusing/repositioning Z axis between job runs). We also have multiple lenses for different focal points. One is only good for etching/surface work, and one is good for cutting 3/8" and thicker materials. We usually use the middle one since 99% of what goes into our laser is 3-6mm stock. > Speaking of help, if anyone wants to review the QSIC design, I'd welcome > that. This is by far the most complex circuit board I've ever designed. I could take a look at it, I have some background in making Qbus and Unibus interfaces, but how useful I'd be depends on what kind of feedback you are looking for. > Back to indicator panels, here's a picture showing a bit of the > evolution of my indicator panels... > > http://pdp10.froghouse.org/qsic/indicator-panel-stack.jpg > > ... The only real thing I'd like to > change is the gloss. Somehow, DEC's inlay is as flat as flat can be. I did notice that. I have no idea what to recommend. AFAIK, DEC just used an acrylic with a specific surface texture. The only stuff I can get is like what you have - smooth as window glass. Cheers, -ethan
Re: RK11-C indicator panel inlays?
On Sun, Dec 5, 2021 at 2:12 PM Noel Chiappa via cctalk wrote: > There is discussion of doing a run of indicator panel inlays: > for the RK11-C (which is wired for an indicator panel, although as far as > I know, DEC never did the inlay). > > If you're interested... you will need a standard DEC indicator panel light > panel (with flat cables with plug-in-cards on the ends). (I don't have any > insight on how to get one of those. It shouldn't be _too_ hard to make > replicas, but I'll leave that topic for the moment.) I have both an RK11-C, _and_ a DX11 light panel sitting around (got it loose some years back) > Starting with that, Dave Bridgham managed to whip up a rough approcimation of > what the inlay would look like: > > http://pdp10.froghouse.org/qsic/inlay-rk11-c.pdf Looks cool. > Anyway, if anyone is interested, the next step would be to find out who all > wants an RK11-C inlay, and work out _exactly_ what would be printed on it. Put me down for one. I've had this RK11-C for a long time and haven't done anything with it. I have always planned to put it back on the 11/20 it came with, but first I need to get the 11/20 going so that's pushed down the RK11-C. This would be really cool as a debugging tool more than just as amazing lights. -ethan P.S. - not to derail things, but definitely loop me in on the (future) thread for making reproductions. I have access to some tools that might make parts of it easier.
Re: PDP-11/70 Boards
On Mon, Nov 29, 2021 at 3:19 PM Henk Gooijen via cctalk wrote: > I think the FP11 boards are not essential for the 11/70 > They only add hardware FP support. Not essential for many uses, but I'm pretty sure UNIX is unhappy without them. If you are going to run RSTS/E or RT-11, should be just fine either way. > However, I think that the cache boards are essential. > Not sure the 11/70 will work without them. Agreed. I think those _are_ mandatory. Cheers, -ethan
Re: IEEE-488 on the PDP-11
On Thu, Nov 18, 2021 at 3:15 AM Christian Corti via cctalk wrote: > On Wed, 17 Nov 2021, Ethan Dicks wrote: > > ... The IBV11 can certainly keep up with the > > 6502 in the drive that's banging out the IEEE-488 protocol. > > Our Tektronix 4051 can talk to and use Commodore IEEE floppy drives for > mass storage. It has a custom ROM extension for it. That's really cool. There are a few non-Commodore systems that were able to talk to Commodore floppy drives. I didn't know the Tektronix 4051 was one of them. Do you know if it works at the flie level or the block level? -ethan
Re: IEEE-488 on the PDP-11
On Tue, Nov 16, 2021 at 6:09 PM Christian Gauger-Cosgrove wrote: > On Tue, 16 Nov 2021 at 16:27, Ethan Dicks via cctalk > wrote: > ... I have experience with IEEE-488 from my many hours > > spent with Commodore PETs. > > > Hmm now that I'm reminded that a large proportion of Commodore's > "stuff" was IEEE 488 or a serialized version thereof. Yep. All PETs have true IEEE-488, albeit a software-driven implementation so it's not high-speed (few kb/sec). Starting with the VIC-20, they used that serialized version, because Jack Tramiel was tired of the cost of cables and connectors. > I kind of want to see now if an IBV11 and Commodore 1541 can be abused > into cooperating. I think it could be done. The IBV11 can certainly keep up with the 6502 in the drive that's banging out the IEEE-488 protocol. > (There'd need to be a small "box of stuff" to turn the real 488 bus to CBM's > serial thing.) You would need a box like that (they do exist) for talking to a later device like the abundant 1541 floppy drive, but you could just plug the cable right into an older drive for the PET, a 4040 dual-double-density 5.25 drive, or an 8050/8250 drive (higher density, more tracks), or even a D9060/D9090 hard drive (5MB or 7.5MB, internally has an MFM drive and a SASI-ST506 bridge). The "DOS" is in ROM in the disk drives, including everything about files and filesystem layout. You wouldn't have to port that to the PDP-11. You talk to all the drives with the usual IEEE protocol of secondary addresses and command strings. On the PET side, it's LOAD/SAVE, OPEN/CLOSE, and PRINT#/INPUT# (later ROMs added a command layer for "disk commands" but they are just wrappers around the primitive calls). The directory is a special file named "$"; to get a directory, you open that file and read the contents. The drive sends the directory not as plain text, but as a loadable BASIC program so you do have to convert "line numbers" (file block sizes) to ASCII, and you have to convert all the text contents from PETSCII to ASCII. All doable in a couple of pages of code. There are a number of books for how the Commodore side works. You can even use the later serialized drive books to understand the higher protocol. At a character level, it's identical. In terms of using it as a more generic device, there are block-level primitive commands (U1 and U2 for read and write-block) but the physical block size is 256 bytes, even on the D9060/D9090 hard drives. I'm sure it's possible to write a native driver for RT-11, bypassing the Commodore filesystem, but it sure would be slow. -ethan
Re: IEEE-488 on the PDP-11
On Tue, Nov 16, 2021 at 11:01 AM Douglas Taylor via cctalk wrote: > In my pile of DEC computer stuff I have a DEC qbus IBV11 IEEE-488 > controller board (M7954) with cable (BN11-A) that connects to the GPIB bus. Fun card. Thanks for starting this thread. I have one too (came with my MINC-11) and I have experience with IEEE-488 from my many hours spent with Commodore PETs. Thanks to all for sharing code and software. -ethan
Re: Sun-2 and Sun-3 mice (eBay)
On Thu, Oct 28, 2021 at 10:00 AM Alan Perry wrote: > Aside from the posts on the side of the connector, what is unique about the > cable and connector? What’s the deal with those posts? Aside from them, it > looks like a 6P4C with only three leads connected. AFAIK, the posts are there so you don't plug your mouse into a phone jack or a modem port. There are cutouts on the back of the Sun3 keyboard to admit that connector. One could almost certainly start with a 6P4C cable and fix up the mouse end and re-use a Sun4 mouse, but for show/display purposes, it would be clearly a substitute. That's why my original plan for home use was to make a Sun4 keyboard cable adapter - if it's just me, I can use a newer keyboard/mouse. -ethan
Re: Sun-2 and Sun-3 mice (eBay)
On Thu, Oct 28, 2021 at 4:46 PM Ethan Dicks wrote: > > Hi, Tom, > > Thanks! That was supposed to be off-list and I even checked recipients... :-( -ethan
Re: Sun-2 and Sun-3 mice (eBay)
Hi, Tom, Thanks! Yes. Sun3 mouse has RJ-11ish connector. It plugs into the keyboard which has a DA15 for the host. Totally different plugs from Sun4 and later. Ethan Dicks 2447 N. 4th St. Columbus OH 43202 On Wed, Oct 27, 2021, 01:09 Tom Uban via cctalk wrote: > Located. It was actually sold for Prime Computer and is black, but is new > in box with pad. > Mouse Systems MSC 401162-019/B with the 6 pin RJ11ish connector that I > believe was used on Sun3 systems. > Let me know you address if you are interested. > > --tom > > On 10/26/21 9:45 AM, Ethan Dicks via cctech wrote: > > On Tue, Oct 26, 2021 at 2:43 AM r.stricklin via cctech > > wrote: > >> > https://www.ebay.com/sch/xi_jinping/m.html?item=334195034340=item4dcf9388e4%3Ag%3Ar%7EcAAOSwFVhhd12t=nc&_trksid=p2047675.l2562 > >> > >> Hadn't realized before that there were Sun-2 mice which weren't black > (were white/beige). I know some folks are looking. > > I am in need of a Sun3 mouse but that one looks like it got pulled out > > from under the porch. > > > > -etha > >
Re: Sun-2 and Sun-3 mice (eBay)
On Tue, Oct 26, 2021 at 5:20 PM Alan Perry via cctech wrote: > >>> https://www.ebay.com/sch/xi_jinping/m.html?item=334195034340=item4dcf9388e4%3Ag%3Ar%7EcAAOSwFVhhd12t=nc&_trksid=p2047675.l2562 > I would be more concerned about paying $50 for an untested mouse. I half expect that the LEDs need to be replaced - that was a common problem with this type of mouse. The IR LED in particular was driven hard and dimmed with age after a few years of being powered on. That's an easy and expected fix. What would be entirely uncool, and was the reason I didn't drop $65 incl postage on it, is if the cable had damage to it. That's the part that's unique to the Sun3, the cable and connector. > The mouse that came with my 3/260 was yellowed but otherwise looked > fine. Unfortunately it doesn't work. Even if the LEDs light up, a mouse that won't track can still have worn-out LEDs. Definitely check that first. If it's totally inert (no bits of any kind, not even button clicks), then that's a different matter. > I still haven't restored the 3/260 enough to be able to use a mouse, but > someday ... I got around to fixing up my 3/60 to bring to VCF a couple of years ago, but I had to borrow a suitable mouse. The other angle I have is to finish my DA15-DIN8 converter so I can use a newer mouse/keyboard. I _have_ a Sun3 keyboard (cost me more than the 3/60!) and I like to have that for exhibition, but just to use the machine, I don't mind using a Sun4 or Sun5 keyboard with it. -ethan
Re: Sun-2 and Sun-3 mice (eBay)
On Tue, Oct 26, 2021 at 10:45 AM Ethan Dicks wrote: > On Tue, Oct 26, 2021 at 2:43 AM r.stricklin via cctech > wrote: > > https://www.ebay.com/sch/xi_jinping/m.html?item=334195034340=item4dcf9388e4%3Ag%3Ar%7EcAAOSwFVhhd12t=nc&_trksid=p2047675.l2562 > > > > Hadn't realized before that there were Sun-2 mice which weren't black (were > > white/beige). I know some folks are looking. > > I am in need of a Sun3 mouse but that one looks like it got pulled out > from under the porch. Looks like someone got it. I figured it wouldn't last long. Really, I can get away with a cable adapter and a Sun4 mouse, or I think I have a Sun4 mouse or two that someone cut the cable off of that can be rewired with the right jack. -ethan
Re: Sun-2 and Sun-3 mice (eBay)
On Tue, Oct 26, 2021 at 2:43 AM r.stricklin via cctech wrote: > https://www.ebay.com/sch/xi_jinping/m.html?item=334195034340=item4dcf9388e4%3Ag%3Ar%7EcAAOSwFVhhd12t=nc&_trksid=p2047675.l2562 > > Hadn't realized before that there were Sun-2 mice which weren't black (were > white/beige). I know some folks are looking. I am in need of a Sun3 mouse but that one looks like it got pulled out from under the porch. -etha
Re: PDP-11 Unix V7M-11 V1.0 under SIMH
On Mon, Oct 4, 2021 at 7:42 PM Chris Zach via cctalk wrote: > Oddly enough I do have a copy of Pro/Venix 1.0 that would fit on a > Pro/350 with a 5mb hard drive. Slow as *dirt*, you could literally watch > the hard drive seek back and forth with the little arm on the side. But > it did work. I have one of those. I brought it to VCF East two years ago for the Mother of all UNIX Demos. I think there's 300-400KB free on that RD50. It is indeed slow as dirt. Also, 'date' only allows for 2-digit years, so I had to write a utility to accept UNIX epoch time to set the date past the Y2K boundary. -ethan
Has anyone gotten the old SIMH VAX-11/730 emulator to boot?
Hi, All, I'm fiddling with my 11/725 and as part of that, I'm prepping possible system images to deploy using the 10-year-old 11/730 emulator that's now part of SIMH. I'm trying to get the original (v3.8) version working because of the numerous changes to how simh 4.0 works now. I'm working from the sources on http://www.9track.net/simh/vax730/ They compiled just fine and the binary runs (on Linux, FWIW) but I've tried booting several different TU58 images and VMS device images and so far, they all tell me "file open error". Here's the current config with me trying to run the CRD tape/disk combo (trimmed just show mounted images on TD0 and RB1). sim> show conf VAX730 simulator configuration CPU, idle disabled, 2048KB, HALT to SIMH . . . TD, 2 units TD0, 262KB, attached to BE-T176I-DE.tu58, write enabled TD1, 262KB, not attached, write enabled . . . RB, address=FFFB86-FFFB87, vector=2A8, 4 units RB0, 64MW, not attached, write enabled, RB80 RB1, 5242KW, attached to CRDPACK-RL02.img, write enabled, RB02 RB2, 5242KW, not attached, write enabled, RB02 RB3, 5242KW, not attached, write enabled, RB02 If I have to, I can grab the source for the current version off of github, but having looked it over, it's essentially this same emulator (with commit dates of 9-10 years ago) plus some recent structural cleanup that's similar across all emulators. The functional parts are this same emulator. Thanks for any tips. -ethan
Re: Found my favorite DOS editor
On Tue, Sep 28, 2021 at 5:30 PM Fred Cisin via cctalk wrote: > "Baby Duck Syndrome": you bond to the first one. Any time you are tempted > to switch, everything that any other one does differently is "just all > wrong". If you are eventually compelled to switch, you will bond to a new > one; and every other one "just does it all wrong". > > 'course, then there are the MAJOR religious battles. Such as VI VS EMACS. I started on 8-bitters. On minis, I first encountered EDT (on VMS), then Emacs (on UNIX, AmigaDOS, and even VMS), then years later when I was working for Lucent/Bell Labs, vi... I'm all kinds of messed up, but mostly I use vi(m) these days. It's not perfect (oh, buy, it's not perfect!) but I can have the same experience going from platform to platform to platform. That's worth it. -ethan
Re: microvax/vs 2000 expansion base circuitry ?
On Thu, Sep 23, 2021 at 6:41 PM Jonathan Stone via cctalk wrote: > I've read that there is circuitry in the expansion base (BA40A?) has > circuitry . Does anyone know what the circuitry does? Is it required for > SCSI operation? (I hope not, or I'll have to kludge one up to make use of > pk2k SCSI boot-roms!) IIRC the DHT32 has a small board in the skirt and the external RD interface may have a board as well. SCSI (for a TK50Z-FA, originally) is just a cable. The 50-pin connector on the mainboard is correctly wired for SCSI. It may well have TERMPWR active and not current-limited though, if it matters to your target. -ethan
Re: Burnable, patched Microvax-2000 SCSI-boot EPROM images?
On Tue, Sep 21, 2021 at 4:37 PM Jonathan Chapman via cctalk wrote: > > The DEC-badged Data-IO " on eBay is tempting, but expensive, and I don't > > know where to find software. > > If it is just a regular Data I/O underneath, head over to the groups.io page: > > https://groups.io/g/DataioEPROM/ One of my Fall projects is to figure out why my Data I/O 29A isn't working. It's been sitting for years and when I got it out last year, it didn't pass self-test. I need to spend some time looking over the posts in that group to see if my symptoms are common. That said, unless you need to program stuff other than 2716-27512 and up in that line, an old Data I/O is probably not what you need. If you need to program chips made before 1985, then it might be a good choice. -ethan
Re: VAXstation 100 ROM image
On Tue, Sep 21, 2021 at 2:04 PM Josh Dersch via cctalk wrote: > (DEC did make a Unibus to Qbus adapter, the DW11-B, but it was unrelated to > the VS100) Yes. I have one. It came in a PDP-11/34 so they could install an IBV11 on a Unibus machine for a Physics Department. Much older than the VS100. -ethan
Re: Burnable, patched Microvax-2000 SCSI-boot EPROM images?
On Mon, Sep 20, 2021 at 5:24 PM Dave Wade G4UGM via cctalk wrote: > Do you know what type of ROM/PROM is needed 4x 27512 (32-bit wide image) I have a MicroVAX 2000 but haven't managed to get that SCSI hack working myself. It's been many years since I last fiddled with it. -ethan
Re: Ultrix-11
On Fri, Aug 20, 2021 at 1:14 PM Bill Gunshannon via cctalk wrote: > > http://ftp.fibranet.cat/UnixArchive/Distributions/DEC/Fred-Ultrix3/setup-3.1.txt > > > > I've installed older versions of UNIX where you had to explicitly set > > up disks and partitions (where you _could_ resize partitions). Prior > > to restoring the contents from tape. That didn't appear to be as easy > > with this installer script. > > I think the intent of the Ultrix-11 3,x install is to make it as > simple as possible to get a system up and running on the hardware > available in the day and then with time and experience one could > create more advanced systems. Yes. I was around in this era and learning to do a from-scratch install was an ordeal. DEC did package things up with a set of questions (vs knowing which lines of which files had to be hand-edited) and incorporated all the supported disks and tapes and serial muxes, etc. All DEC, of course, so if you had 3rd-party hardware you were out in the wilderness (we provide such a 3rd-party intelligent serial device into this environment so I know how hard it could be). If you had a standard DEC box, it was fairly push-button. That was part of their magic. It mostly worked. > I hope, eventually, to make a system > with four RA81 disks with root and usr occupying entire RA81's and > two more for User files. Wow! That's way bigger than our biggest machine at work in 1993. We had that 11/750 (that I upgraded to 8MB including adding the extra memory address line on the backplane) and it pinged back and forth between VMS 4.5 most of the time and Ultrix-32 3.something as needed for customers. It had a dedicated Fuji 160MB drive that mapped as two RM03s and a Fuji Eagle that used the RM05 device entry but patched for full capacity (400MB) plus that $26,000 RA81 - Total of just under 1GB on 3 spindles and two controllers (Unibus and CMI bus). When this box was running UNIX, I was the only user so I usually did that off-hours so everyone else could use VMS for workday tasks. > sadly, using an RA81 still only gives you: > /dev/ra01 95982849674930%/usr Tiny! > Those were the days. Sadly, most people in the business today know > nothing about them. The forgetting of this environment is why recently there's a push to collapse all UNIX system binaries into one place because "kids today" have never been on a system where the operating system is spread across multiple spindles for space/cost/performance reasons. Everyone is used to massive drives where the OS takes up 1% or less of the entire disk and you only really worry about space for logfiles or /var/tmp so that userland programs that leave big messes don't crush the boot volume with endless spewage. With variable-zone disks (1990s tech) people stopped bothering to try to tweak performance on cylinder boundaries because you used to have 14 heads and track-to-track switching was 10X faster than stepping. Some parts of the old UNIX dance I do not miss. ;-) -ethan
Re: Ultrix-11
On Fri, Aug 20, 2021 at 11:50 AM Peter Allan via cctalk wrote: > I just installed Ultrix-11 3.1 using the ultrix31.tap file from > https://pdp-11.org.ru/files.pl?lang=en > which is the location from the comments in Stephen's Machine Room video on > YouTube that I think started this thread. > > It installed just fine, but just like the video, I ran out of space on /usr. /usr was usually tight back in the day. > How can I make a larger /usr partition? Is it possible to do this at > installation time? There did not seem to be an option for this. Can it be > done by using an additional disk? That would seem likely, but not what a > system manager back in the 70's or 80's would expect to need to do, > especially as there is a relatively large amount of space left to create > /user1. In the 70s and early 80s, it was not at all uncommon to have multiple disk drives mounted to add up to enough space, especially to put user files on their own device to keep them from competing with free space in the system areas. Also, older, smaller disks were often cheaper than the newest/largest disk drives, or systems would be put together from repurposed hardware rather than purchasing new. For a single data point, my employer bought a new RA81 in 1984. For 424MB it was $24,000. Most machines had a _lot_ less disk in those days. Our main UNIX machine was an old 11/750 (2MB RAM) with 2x RK07 (28MB each). It was quite a jump when I put Ultrix 1.1 on an 11/730 w/RB80. The CPU was 30% slower, but it had 5MB of RAM and a 121MB disk, so as a machine that spent most of its time with a single user (me), it was fine. When disks were routinely 1-30MB (RK05... RK07 or RP03), it was totally common to have 2-3 disks on a machine. All that said, I looked over this install write-up and it seems to assume you have one disk and it slices and dices with default sizes... http://ftp.fibranet.cat/UnixArchive/Distributions/DEC/Fred-Ultrix3/setup-3.1.txt I've installed older versions of UNIX where you had to explicitly set up disks and partitions (where you _could_ resize partitions). Prior to restoring the contents from tape. That didn't appear to be as easy with this installer script. > I noted the options for installing software using soft links to other > locations. Was that the preferred method when installing additional > software? That was done, as was mounting an entire second disk for /usr. One of the challenges is making sure you have enough tools accessible on the boot device to bring the machine up far enough to mount the additional devices. This is part of why there are system tools in /bin, /usr/bin, etc. You could depend on the contents of /bin being there before /usr was mounted. Also, traditionally, programs in /bin were statically linked so that you didn't have to have specific libraries available at the time. The simplest solution, of course, is just get a bigger disk, but where that wasn't possible (which was most of the time), people did use soft links or multiple spindles to aggregate enough space to get by. Back in the day, I struggled to get enough disk space to install 2.9BSD on an 11/24. Two RK07s would have been a luxury. I had an RL02 (10MB) and I think maybe an RL01. I could get the initial restore to work but I didn't have enough space to rebuild my kernel. -ethan
Re: ISO Laserjet I/II/III firmware
On Thu, Aug 12, 2021 at 10:48 AM Al Kossow via cctalk wrote: > I suspect interest in emulating them will die out once they get past the > 68000 models. I may still have a II, and I definitely still have at least one (functional) III and a 4Si I still use my 4M/L all the time - Postscript + LocalTalk + IEEE1284. It's a great little printer. -ethan
Re: Install Floppies (Was: Compaq Deskpro boards/hard drives from
On Mon, Jul 26, 2021 at 6:02 AM Peter Corlett via cctalk wrote: > The Amiga could get 880kiB on a DD disk, and 1760kiB on a HD disk if you have > one of those hen's teeth drives which spin at 150RPM. It does this by doing a > read-modify-reformat of the entire track of 11 or 22 sectors, which allows > omitting all of the guard bands except for the one between the start and end > of > the track. In particular, the Amiga trackdisk.device driver would start by spinning up the disk motor, then writing out about 10% of a track of gap bytes, then emit all 11/22 sectors in a tight line, (intentionally) overwriting some of the just-written gap bytes. The little transition right at the end where the write stopped was irrelevant since it would just be skipped over by the find-the-first-sector scheme. It also meant that you didn't have to wait for part of a rotation for your sector to come around. As soon as the disk was up to speed, you could begin writing immediately. The "disk controller" was really a giant shift register that read or wrote media-ready bits. The encoding/decoding happened in RAM, using part of the graphics subsystem to transform unencoded-binary blocks to/from MFM-encoded data. Screwy but it was pretty flexible. Reading/writing "DOS floppies" was a simpler process, and there was a different diskette driver for that (mfm.device) and a filesystem handler that knew about the FAT filesystems. -ethan
Re: What's left of the Houston Museum stuff
On Wed, Jul 21, 2021 at 10:52 PM Cameron Kaiser via cctalk wrote: > > > "Houston Computer Museum" ... I wouldn't call this a "museum". The > > > condition of the stuff is fitting for a garbage tip. It is a disgrace. > > > > Isn't this the place in Texas that flooded last year? > > Houston and floods ... I got stranded in Houston for two days on my last trip there. Flooding around the airport caused a multi-day disruption in flights. -ethan
Re: Looking for VAX6000 items
On Tue, Jul 13, 2021 at 10:21 PM Brian Roth via cctalk wrote: > Its going to be interesting for sure. I am currently running some better > power into the shop. The requirements for the 6000 is 3 phase. I just > finished reassembling the power inlet box and I'm pretty sure it will run > fine on 2 phases. I had to trace the right phases to energize the contactor > and power the convenience outlets. My memory for most of the larger VAXen is that they balanced power supplies across the phases, and *might* have used 3-phase blower motors in the biggest boxes (8800 for example). Definitely check wiring, but the 6000 series may well have single-phase blowers. When we got an 8530 at work in the early 90s (needed a machine with a Nautilus bus for specific hardware testing), it was definitely a 3-phase machine and since we were in an industrial setting, I just tapped into our panel at the back of the warehouse and wired up a 3-phase outlet for it. It never sat on our datacenter floor as a result, but it really only ever had one purpose and that wasn't a daily driver. Too much power, too much heat for so few employees (at that stage of the company). -ethan
Re: First new vax in ...30 years? :-)
On Mon, Jul 5, 2021 at 9:37 PM Zane Healy wrote: > > On Jul 5, 2021, at 5:05 PM, Ethan Dicks via cctalk > > wrote: > > > > On Mon, Jul 5, 2021 at 2:46 AM David Brownlee via cctalk > > wrote: > >> In case anyone was interested in an FPGA VAX implementation > >> http://mail-index.netbsd.org/port-vax/2021/07/03/msg003899.html > > > > I think this is fantastic, but getting the CPU running is only the > > start. I'll be curious what/how storage emulation goes, and > > networking. Bonus points for sync serial that can run a DDCMP line to > > vintage machines. > > I found myself wondering what it would take to put this, RAM, network, and a > SD Card “Disk” on a Q-Bus board. :-) Adding a Qbus to it would certainly offload the work of implementing storage - just put it on the user to find a Qbus SCSI card or a KDA-50 or a Qbone or whatever and you wouldn't have to worry about OS drivers or (alternately) mimicking a vintage disk controller. I would hope it would use its own RAM. No point in forcing anyone to use vintage RAM. For convenience, it would be nicer to have some sort non-spinning disk rather than a $$$ vintage controller. -ethan
Re: First new vax in ...30 years? :-)
On Mon, Jul 5, 2021 at 2:46 AM David Brownlee via cctalk wrote: > In case anyone was interested in an FPGA VAX implementation > http://mail-index.netbsd.org/port-vax/2021/07/03/msg003899.html I think this is fantastic, but getting the CPU running is only the start. I'll be curious what/how storage emulation goes, and networking. Bonus points for sync serial that can run a DDCMP line to vintage machines. -ethan
Re: VT340 Emulation
On Tue, Jun 22, 2021 at 6:32 AM Grant Taylor via cctalk wrote: > > I would love to see REAL RS232 on a RBPi, probably even the original > > MMJ from DEC for keyboard & mouse > > What is a /real/ RS-232? How does it differ from USB-to-RS-232 and / or > bit banging GPIO lines? The OP said he meant with "real" connectors, but in my case, I've encountered strange buffering issues with USB serial dongles (since they are really block-mode devices, not character-at-a-time) and I've definitely had problems supporting lines with odd parameters (especially speeds slower than 300 baud or with 5-bits-per-char, like one would use for a Model 19 or Model 28 teletype). The hardware UARTs on AVR processors implement those juse fine (though for "50 baud", you often have to put a slower crystal on the processor because the 16-bit divisor overflows at 16-20MHz). The "soft serial" libraries often just hard-code 8-bit implementations. Fine for modern stuff but I have uses for connecting to electromechanical serial devices. In terms of a CRT terminal, though, most modern serial implementations are fine. -ethan
Re: VT340 Emulation
On Mon, Jun 21, 2021 at 11:14 PM Douglas Taylor via cctalk wrote: > Wow, that is very helpful. I had downloaded xterm from > invisible-island.net and executed a ./configure. I complained that I > lacked the Athena X widgets, so I paused on it. I got that. On a RHEL7 box, I did: $ sudo yum install libXaw-devel.x86_64 It built cleanly. I'm about to test it. -ethan
Re: VT340 Emulation
On Mon, Jun 21, 2021 at 4:12 PM Grant Taylor via cctalk wrote: > On 6/21/21 1:07 AM, Ethan Dicks via cctalk wrote: > > I'm not the OP, but I'm interested in fiddling with ReGIS a little. > > I just pulled out my VS240 and fired it up. Right now, I have a > > VR201 on it, but I also have a VR241 for it as well. > > Let me know if you would like some sample ReGIS files. I have a few of > them at hand. I even managed to create one by hand with little effort. I would love some sample ReGIS files, color or B Anything, really. Thanks! -ethan
Re: VT340 Emulation
On Mon, Jun 21, 2021 at 2:47 AM Grant Taylor via cctalk wrote: > On 6/18/21 5:50 PM, Wayne S via cctech wrote: > > We didn't really need Regis graphics so we never tested that out. > > I'm not sure what the OP's use case is, but if they / you are wanting > ReGIS (or Sixel) graphics, XTerm supports (both of) them. I'm not the OP, but I'm interested in fiddling with ReGIS a little. I just pulled out my VS240 and fired it up. Right now, I have a VR201 on it, but I also have a VR241 for it as well. -ethan
Re: DEC Computer Lab for sale
On Sun, May 30, 2021 at 11:42 AM Vincent Slyngstad via cctalk wrote: > https://so-much-stuff.com/pdp8/computerlab/computerlab.php > The photos get a little bigger if you click them. Those bits of stamped > brass or whatever they are made of were probably pennies each. I've thought about what it might take to manufacture a pair of steel rollers that could stamp those out but I haven't gotten very far with it. Same idea for the backplane bus strip DEC used to sell on the roll. Depending on level of detail, either a small CNC or possibly a wire EDM could make the dies. -ethan
Re: DEC Computer Lab for sale
On Sat, May 29, 2021 at 10:58 AM William Donzelli via cctalk wrote: > Over on the Discord, I have posted a DEC Computer Lab H-500 for sale. > Needs cosmetic help, but will be priced accordingly. I already have one, but it has no wires and a reasonable substitute has not come to light despite occasional discussions over the past 20 years. But they are really cool. -ethan
Re: DECNet for Pro 300 series boxes
On Mon, May 17, 2021 at 8:53 PM Paul Koning via cctalk wrote: > There are two comms option cards: the DECNA Ethernet, and the 3CA quad UART > (a very obscure device). Yeah... I have neither of those, but at least I've seen a picture of a DECNA. > The other limitation is the software. DEC only supplied P/OS, RT-11, and > Ultrix (or was that some other Unix? Not DEC, but there was VENIX from VenturCom. I have VENIX 1.0 on a Pro350, and there was VENIX 2.0 for the Pro380. No idea about DECNA support in 2.0, but I have the (paper) manuals for 1.0 and there's no mention of it. I think a TCP stack might crush an F-11. You could run TCP/IP on a 2.11BSD system, but that required a Split I processor and that means a J-11 (or a larger Unibus box, in practice). -ethan
Re: PDP-11 SPACEWAR running again!
On Wed, May 12, 2021 at 1:11 AM Lars Brinkhoff via cctalk wrote: > There are also at least two GT40 implementations of Spacewar. One from > MIT, by Dick Waters, and another from SAIL, by Bo Eross. They run fine > on SIMH, but it would be nice to see them on real hardware too. Is there a web page I could check that would include the hardware requirements? I don't have a GT40, but I have a VT11 (4-slot backplane and cards) and an assortment of Unibus PDP-11 processors (11/04 or 11/34 would be the easiest to configure, but I have others). I don't have the keyboard, lightpen or a tube yet. -ethan
