Try here… From an old newsgroup Just a note that Jerome Fine collected together a set of 24 RT-11 releases (from V01-15 on a DECtape to V05.07 on an RL02 disk) in the form of a consolidated CD-ROM image. You can download the CD-ROM from http://pdp-11.classiccmp.org/RT-11/dists/RT11DV50.ISO.zip Sent from my iPhone On Jan 20, 2025, at 13:56, Tom Uban via cctalk <cctalk(a)classiccmp.org> wrote: On 1/20/25 15:26, Martin Eberhard via cctalk wrote: I'm in the process of restoring a PDP11/20. Here is what is working so far: KA11 PDP11/20 CPU , power supply, programmer's console, etc. 32Kx16 SRAM/ROM board of my own design (Core memory will come later!) KE11-A Extended Arithmetic Element RX211 controller with RX02 drive, cleaned, spindle bearings replaced, aligned, tested, and working DL11-W Serial Line Unit with Real-Time Clock DL11 2nd serial port, modified to operate at 19,200 baud VT100, connected to the DL11-W I've written a program that lets me load a raw disk image (via Xmodem protocol) from the serial port onto a floppy disk, and verify the write. This works great, for both single-density and double-density. (It can set the media density as needed too.) I'm now looking for a bootable RT-11 floppy disk image (just a raw image, e.g. .IMG) that can boot and run on this limited hardware. The file should be exactly 256,256 bytes long if single-density, or 512,512 bytes long of double-density. (Actually, anything bootable on this hardware would be appreciated!) I'm new to this forum - let me know what is the protocol for giving you my email address... Thanks! Martin E. I'm not sure if this is what you are looking for, but bitsavers.org is a great resource: https://bitsavers.org/bits/DEC/pdp11/rt-11/ Where are you located? --tom

On 1/20/2025 Wayne S wrote: I didn't write the following, I'm just copying what I saved some time ago. It may help you make use of RT11DV50.ISO.zip . -- Ron Subject: RT-11 distribution kits From: Tony <agn...(a)gmail.com> Date: 9/24/2021 A few people have asked me about RT-11 distribution kits. Earlier this year I posted the following to the alt.sys.pdp11 USENET newsgroup. It may be of use to fellow PiDP11 owners... just merge the relevant disks mentioned below into the /opt/pidp11/systems/rt11/boot.ini and boot the CD-ROM (boot rq0) to make a distribution kit. Tony The following is my posting from alt.sys.pdp11 - Just a note that Jerome Fine collected together a set of 24 RT-11 releases (from V01-15 on a DECtape to V05.07 on an RL02 disk) in the form of a consolidated CD-ROM image. You can download the CD-ROM from http://pdp-11.classiccmp.org/RT-11/dists/RT11DV50.ISO.zip If you're using SIMH PDP11 you can access distributions from RT-11 partitions on the CD-ROM using a SIMH ini file like - ; File rt11.ini for SIMH PDP11 set cpu 11/70, 4M set cpu noidle set throttle 10% set dz disable set hk disable set tm disable set rq enable set rq0 cdrom att rq0 RT11DV50.iso ; This is for copying an install disk to a RL02 disk image ; For older versions use DECtape (tc) or RK05 (rk) set rl enable set rl0 RL02 att rl0 RT11V57.dsk boot rq0 ; end of rt11.ini Unzip the CD-ROM from the zip file into an empty directory with the above rt11.ini and start SIMH PDP11 $ pdp11 rt11.ini PDP-11 simulator V4.0-0 Current git commit id: 852c0bc1 Disabling XQ /Users/tony/rt11/rt11.ini-7> att rq0 RT11DV50.iso RQ0: 'RT11DV50.iso' Contains RT11 partitions 4 valid partitions, Type: V05, Sectors On Disk: 242406 /Users/tony/rt11/rt11.ini-13> att rl0 RT11V57.dsk RL0: creating new file: RT11V57.dsk Overwrite last track? [N]Y RT-11XM V05.03 ?LD-W-Unable to update disk copy of LD handler .TYPE V5USER.TXT [snip] Each of the CD-ROM four partitions is available as device DU0:, DU1:, DU2: and DU3:. There are two files on DU0: called README.1ST and README.2ND you should examine for instructions and the layout of the CD-ROM. For example, to make a bootable RL02 disk containing the RT-11 V05.07 installation kit, copy the disk-image file from DU2:RTV5RL.07 to the RL02 media using - .copy du2:rtv5rl.07 /file DL0: /dev DL0:/Copy; Are you sure? Y Output device is larger; Are you sure? Y Now you have the installation disk on the RL02 in drive DL0:. You can now perform an installation by booting this disk - but to do this you should halt SIMH PDP11 and revise the start-up file to add another RL02 device (as rl1), and boot from rl0. See the appropriate RT-11 installation guide for details (installation normally requires two additional RL02 disks - one to make a backup of the installation disk, and the other to make your working system disk). The release notes are at - http://www.bitsavers.org/pdf/dec/pdp11/rt11/v5.7_Oct98/AA-5286M-TC_RT-11_V5… and you can use this in conjunction with the V5.6 documentation at http://www.bitsavers.org/pdf/dec/pdp11/rt11/v5.6_Aug91/ Tony

I looked at those images on Bitsavers. As far I understand, an RX211 controller can't boot a disk with an RX11 bootstrap program. The RX211 uses DMA to transfer the data, while the RX11 requires software to transfer the data in a loop, one word at a time. Additionally, RT11 (or any other OS) has to be configured for the RX211, differently than for the RX11, for the same reason. (A good driver would look at the status register and detect whether it is an RX11 or RX211, and adjust accordingly. I don't know if DEC did this or not.) Every single-density image that I could find either does not have a boot loader (Track 1, sector 1) or it has a boot loader for the RX11 controller. I have not yet found a disk image (single-density or double-density) for an RX211 that is bootable. This would require both the boot sector to be for the RX211, as well as the RT11 image itself, configured for an RX211 drive. (Or configured to detect the drive type and do the right thing...) I'm kind of new the the DEC world (aside from learning PDP11 assembly language in collage...) Any pointers, advice, DISK IMAGES, etc. is greatly appreciated :-) Thanks, Martin E.

For those not on the Discord (it's great) here is my thought: Since the 11/20 has two serial ports, set the second to 176500/300 address/vector and hook it to a PC running a TU58 emulator. Then toggle in a TU58 bootstrap, and boot up RT11 on the emulated TU58. Then pop in a floppy and do a format, then copy over all the files with a copy/sys du0:*.* dy0: followed by a copy/boot dy0:rt11fb.sys dy0: and boot up off the floppy. Much simpler than trying to transfer images and whatnot. C On 1/20/2025 7:28 PM, Wayne S via cctalk wrote: