If you read the previous posts to this thread, it does not seem as if RT-11 (or any other OS) is available, as yet, to run VTSERVER, let alone any other program such as Kermit. Dough, can you let us know if you attempted my <CTRL/C> suggestion? Are you able to find an RL01 pack with RT-11 (or any other OS)? Do you have the ability to produce a simple standalone program to copy an image file to an RL01 which you can (PAINFULLY) enter via ODT? How many serial ports do you have? Do you have a blank RL01 pack to work with? Jerome Fine

On Saturday (05/21/2011 at 09:31AM +0100), Pete Turnbull wrote: That's right... The first step vtserver performs is to chat with ODT and "toggle in" a trivial serial port bootstap. It uses "L" and "D" to deposit that bootstrap at origin 1000 I believe and then executes it. Then it sends a "copy" program which understands how to talk to various RL, RX, etc devices and the VT device which is the virtual tape interface across the serial port to the list of files you have configured into vtserver. down to the RL sector by sector. You do have to be a little careful if the destination RL has bad blocks because this scheme does not account for those. It puts the image file to the destination media at exactly the same blocks as they are in the image file. Chris -- Chris Elmquist

At 11:16 PM -0400 5/23/11, Mike Loewen wrote: With that little RAM, that's actually a good question, and I'm curious to see what others come up with. I think at least early versions of RT-11SJ will fit. The OS that comes to mind is the Paper-Tape OS, though I don't know if it supports an 11/03. Another problem is your available I/O. Zane -- | Zane H. Healy | UNIX Systems Administrator | | healyzh at aracnet.com | OpenVMS Enthusiast | | | Photographer | +----------------------------------+----------------------------+ | My flickr Photostream | | http://www.flickr.com/photos/33848088 at N03/ |

On 05/23/2011 11:16 PM, Mike Loewen wrote: Yep the 780s used a LSI11 as a boot diagnostic processor. It was there to copy the microcode into ram. The 780 had a minimal microcode in rom but the major part was soft loaded. When diagnostics were needed the LSI 11 could load alternate microcode for that and I believe do some system monitoring. With 8KW you need a really old copy of RT11 maybe V3 or V2 and it would not do much. However finding another 8KB or even a 32KW ram board is not that hard and then any version is runnable. the minimum for a runnable system is 16KB if memory serves. With a single 32KW you actually get 26KW of ram and the rest is mapped out for IO. Allison

At 9:48 AM -0400 5/24/11, Dave McGuire wrote: Now those are fighting words... I find v5.4 and higher to be very capable. Zane -- | Zane H. Healy | UNIX Systems Administrator | | healyzh at aracnet.com | OpenVMS Enthusiast | | | Photographer | +----------------------------------+----------------------------+ | My flickr Photostream | | http://www.flickr.com/photos/33848088 at N03/ |

You are either unaware of Multi-User Basic under RT-11 or you may have not remembered. While RT-11 has no file sharing capability and is certainly slow when run on a PDP-11/23 and limited in the size of files when only an RK05 is available, Multi-User Basic was available even before 1980 under RT-11. The Chicago Tribune required a system to handle their multi-million dollar newspaper printing presses. 11 computers had to be co-ordinated (using just 9600 baud serial lines - so there was a maximum of only 11 characters per millisecond and only very rarely was more than one computer active at a time) along with a data base that was kept of the 400 plates per day needed to print the newspaper. In 1981, the editorial offices were a few miles from the printing presses and sending a physical negative of each page was too time consuming. A microwave link was used to transmit the data for each page which then directly produced the physical plate for the press. The microwave signals had to be turned on within a time window of about 100 milliseconds, so the PDP-11/23 was quite adequate even when the signal had to be sent to 6 plate makers within that window. Multi-User Basic supported up to 4 users who entered the data as to which plates had to be made that day and which plates had been completed. It ran as a virtual background job under RT11XM. The foreground virtual job scheduled the 11 tasks controlling the 11 computers making the plates as well as the microwave switch. The foreground job scheduled each job on a round robin basis when there was any input character present to process and when finished gave the rest of the CPU time (probably over 95%) to Multi-User Basic. All this was done in 1981 with V04.00 of RT-11 with just 256 KB of physical memory. I don't know if it was ever upgraded to a PDP-11/73, but that would have been just a hardware upgrade. So while I agree that RT-11 is not often used in this manner, it can be done under the correct situation. In addition, while I agree that for a multi-user environment, scheduling a job based on its priority is essential, I have 6 VT100 terminals on my desk for the real PDP-11. System jobs are used to run 5 of the VT100 terminals in EDIT mode so that I can look at sufficient portions of the listing files which are produced by MACRO-11 along with having enough of the program listing displayed when I am debugging the program under SDX.SYS which freezes the complete system when stopped at a break point. While a bit inconvenient, it was not so difficult that switching to TSX-Plus was worth while to allow access to different parts of the listing as I progressed through the program. So, again, within a single user situation, RT-11 does easily support multiple jobs or multi-tasking, especially so under RT11XM with multi-terminal support. After I had set up this system, I stopped making hard copy listings of my programs and kept all of the current listings on a 600 MB ESDI hard drive. I have migrated the identical software to my PC and run Ersatz-11. The only difference is that the system runs many times faster than the PDP-11/83, the available disk space is many times larger, and there is only the single PC monitor on my desk with one keyboard - that is switched in less than 1/10 second supported by E11. In fact, it switches so fast that I can eyeball the different screens to detect where a listing changes to easily determine the differences (as long as the different copies of the same file are aligned, of course, with the same characters in the same location). I hope that my example of how I use RT-11 has convinced you that RT-11 (within the limitations due to the scheduling algorithm) is just as much of a "multitasking/timesharing" system as RSX-11 and RSTS/E. I often set the background task to execute a command file which assembles and links the current program beng developed WHILE I use the system EDIT jobs to look at the listing of the program, especially when the program has many subroutines and many assemblies combined into one program at the end. Jerome Fine

I totally agree. I was only attempting to point out that looking a bit more carefully under the hood of RT-11 is helpful. If I were to actually use reasonable multi-tasking under an RT-11 environment, I would use TSX-Plus. Except that back in 1980, the system hardware would not support the 11 real time tasks. Very much so. And it was a low speed, low cost application for low budget and limited use. Under RT-11 after V05.00 arrived and supported all 4 MB of extended memory (and memory eventually became less expensive), having 64 KB to always run MU-Basic is great. I have not run MU-Basic under Ersatz-11, but is would now be very fast. You could now run MU-Basic as a system job and leave the background job available for regular RT-11 commands. Very well. A "User Id" and "Password" file that can be managed by the SYSADMIN. I don't have the manuals handy, so no details. I was only helping you to remember how useful and fun RT-11 can be as well as letting others know why I am so addicted to RT-11. RT-11 was probably so much less expensive at just (about) $ 2000 for the distribution and DOC set that it made a lot of sense. Often the primary purpose of a PDP-11 used so little of the CPU time that the CPU was idle most of the time. On one system performing data acquisition, I placed that job in the foreground and ran MU-Basic for a group of engineers without access to any computers back in 1981. It was great while it lasted for a few years. I modified the USR to record the Modification Date and Access Date so that I could "backup" the older files. After 6 months, no one ever asked to have files "recovered". Jerome Fine

Hi Does anyone have a copy of the Comdyna Microhybrid I manual? Dwight

Hi Dave I've had mine for a number of year now. It was from eBay though. I had it up at the MakerFaire in San Mateo last weekend. I was using it to do spirographs on a plotter. It seems that Bob R. has a pdf of it in his scanned stuff :) He sent me a copy. Now I'm happy. I do have a 766 unit that plugs into a PC ISA bus. It has connectors for the GP-6 with Microhybrid so I need to make an adapter to convert it to the LGP-20's pins. Dwight

On 26 May 2011 at 20:03, William Donzelli wrote: Will, you're conflating this thing with the veneered and generated name of Royal-McBee! The Comdyna tower-of-something was the LPG-20. (The R-McB was LGP-30 and -21). --Chuck

On 26 May 2011 at 20:41, William Donzelli wrote: Heh, I guess you're right and my mind dropped a bit. The image: http://3.bp.blogspot.com/_FMBJEkaC8Lw/RcZeulj8YCI/AAAAAAAAALM/vBRWjZRM gVQ/s400/caf6_3.JPG Clearly shows a LGP-20 on the panel, where the caption says LPG-20. 'Scuse my knuckleheadedness, Chuck

Sorry, I already threw them in recycling. -- Will

On 5/27/11 6:32 AM, William Donzelli wrote: I hope you're joking. You and I talked about these and the manuals when you called me.

On 5/26/11 10:29 PM, dwight elvey wrote: CHM is looking for a couple of GP-6s to demonstrate the principles of analog computing, if anyone knows of any available.

At 10:29 AM 5/25/2011, Dave McGuire wrote: I cut my programming teeth on MU-BASIC. In 1979 or so, my high school was fortunate enough to get a 11/03 from the local DEC rep. I think it supported a VT-52, a VT-55, and an LA-120. The weird single-line graphics mode of the VT-55 was intriguing to me. It seemed so much more high-res than the blocky graphics of the IMSAI 8080 that the Computer Club constructed. I remember trying to create an arbitrary line-drawing subroutine that borrowed dots from other lines, but I think it ran out of RAM. By '81 at UW-Madison, I picked up a part-time programming job in MU-BASIC. - John

On 5/24/11 12:10 PM, allison wrote: No, from a connect-ten-terminals-and-a-few-modems point of view. I never said it was. I just said it doesn't do much, which is true. It's a bit more capable than CP/M. Wonderful and fantastic for single-user, single-terminal work...but that's about it. My only experience with PDP-11 systems in production at work years ago was multitasking, multiuser applications, so that's where my interests lie. For single-user, single-tasking stuff, I'm a CP/M guy. That said, I do use RT11 quite a bit, but my primary PDP-11-related interests lie with the "bigger" OSs and system configurations. This is a matter of point of view, yes...but from a RSTS/E and RSX-11M point of view, not a "quadcore terabyte Interet connected 3dHD" point of view. You should know me better than that by now. -Dave -- Dave McGuire Port Charlotte, FL

On 5/24/11 5:18 PM, allison wrote: I love that flexibility of the PDP-11 family. I never did much PC stuff. I worked as a DOS apps developer (in assembler, C, and Clipper, which is a dBase compiler) for a while, and had a DOS machine at home. This was when 286/16 machines were current and 286/20 and early 386/16 motherboards started appearing. I still had the PDP-11 at home and used it, and later a MicroVAX, as my main machine. My PC was primarily a terminal and a data-interchange machine for the PDP-11 and (later) the VAX. I'll get you for that! ;) Indeed, that would not be me. ;) I used PDP-11s at work (Princeton University) at an after-school job that went full time after graduation, then I became a commercial VMS sysadmin for a gaggle of MicroVAX-IIs, IIIs, and an 11/750 at a Defense-related facility. My first home computer was briefly an Atari 800, followed by an S-100 CP/M machine, followed a few months later by...you guessed it, a PDP-11/34, running RSX-11M v4.1 and later RSTS/E v9.4. I ran the CP/M machine and the PDP-11 together for a long time. After that, I got a VAXstation-II/GPX and ran Ultrix as my main platform. I sold the PDP-11/34 (but now have more) and I still have the S-100 system. I retired the VAXstation-II/GPX and moved to a Sun-3/50, then a Sun-4/110, then a SPARCstation-1+, then an -IPX, all running SunOS 4, then a string of SGI machines running IRIX, then MacOS X on the desktop and Solaris on UltraSPARC in the datacenter, which is where I am now, and will be for the foreseeable future. I don't mind that a lot of people here never used these machines before they started "collecting" them because they're "vintage". However I DO become irritated when those people assume that everyone here is in the same boat and only recently saw their first PDP-11. I'm guessing that irritates you as well. I still love Ultrix. I ran it as my main desktop OS (the aforementioned VAXstation-II/GPX, four-plane VCB02 running in grayscale mode) for a long time. It's a bit quirky compatibility-wise, but it's a rock-solid OS. -Dave -- Dave McGuire Port Charlotte, FL

On 5/24/11 6:53 PM, Ian King wrote: Oh, wouldn't they be pissed! ;) -Dave -- Dave McGuire Port Charlotte, FL

At 3:53 PM -0700 5/24/11, Ian King wrote: Oddly enough my first experience using *true* IBM PC's was to connect to a Honeywell DPS-8 Mainframe running GCOS-8. In fact other than using a Mac to play a couple Infocom games, that was my first experience to a Mac as well... Technically my first experience with UNIX as well since the Mac was running A/UX. Much nicer in both cases than the ancient Honeywell terminals we had. Zane -- | Zane H. Healy | UNIX Systems Administrator | | healyzh at aracnet.com | OpenVMS Enthusiast | | | Photographer | +----------------------------------+----------------------------+ | My flickr Photostream | | http://www.flickr.com/photos/33848088 at N03/ |

On Tue, May 24, 2011 at 4:18 PM, allison <ajp166 at verizon.net> wrote: I feel fortunate that for a year or so, I made my living writing application and graphics code on RT-11. There probably aren't many people under 50 now who had the chance for that experience. It was a joy to code on, and 99% of what I did was in MACRO-11. The other guys at my shop at the time were coding in Turbo Pascal on Everex PC-AT clones. I did not envy them. I encountered VMS first, then UNIX (4BSD), then Ultrix, then RT-11 - all within a couple of years. Dabbled with RSTS and RSX, but never enough to get good at them. Great times! -ethan

Mike Loewen [mloewen at cpumagic.scol.pa.us] wrote: That's pretty low-end - probably best suited to running the VAX-11/780 console software - I'd concentrate on getting hold of the rest of 780 :-) I don't recall RT-11s memory requirements, you might be able to run SJ in that? Antonio arcarlini at iee.org

I thought the whole point of VTSERVR was that it didn't need anything on the target PDP11. I've mever used it, but doesn't it enter a program on the PDP11 using console ODT (the host machine automatically enters the octal values and waits for the repsonse) and then uses that to pull the rest of the stuff over. -tony