Once I took at look at the filenames and some of the file contents, it was pretty obvious that this was based on the DECnet-11M code base. I was project leader for DECnet-11M+ Phase III, so that made it a lot easier.
John. > On Mar 10, 2026, at 4:05 AM, Hans-Ulrich Hölscher <[email protected]> > wrote: > > Thank you very much for sharing your notes! > > How did you get that working? > Do you have the manual or did you manage it through trial and error? > > Ulli. > > Am Di., 10. März 2026 um 04:56 Uhr schrieb johnforecast--- via cctalk > <[email protected] <mailto:[email protected]>>: >> I have been able to bring up the DECnet-RT images, that Jay posted a few >> weeks ago, on OpenSIMH. Below are my notes on how to get it running. >> >> John. >> >> >> Notes for getting DECnet-RT V2.1 running on OpenSIMH >> >> NOTE: DECnet-RT is a phase III system so it does not understand Phase IV >> areas >> and can only address nodes in the range 1 - 255. If you attach it so a >> Phase IV router (e.g. PyDECnet) it can be accessed as node nnn in the >> area that the router is in. If you are bringing it up as part of a >> larger network (e.g. HECnet) make sure you "own" it's address otherwise >> you may cause routing problems. >> >> I have tried running DECnet on most versions of RT-11 from 5.0 to 5.7. Any >> version after 5.4D has various problems with file/terminal I/O. >> >> The available images will only run on an unmapped system with >> background/foreground support. This means that everything; monitor, disk >> driver, DECnet and application must fit in 28KW. Later versions of RT-11 >> slighly increased the size of the monitor and/or disk drtiver so that NFT and >> FAL will not fit in memory. DECnet-RT requires features that are not provided >> in the distributed monitors so you will have to generate a new monitor (See >> RT-11 System Generation Guide). You can take all of the default answers >> except: >> >> "Do you want the single job monitor?" Answer N >> >> "Do you want device time-out support?" Answer Y >> >> "How many extra device slots do you want?" Answer 4 >> >> >> Once you are running the new monitor, copy all the files from the 3 RX50 >> floppy images (RX0808.IMG, RX0809.IMG and RX0810.IMG) to your system device: >> >> COPY/SYS DUx:*.* SY: >> >> The system is configured to use a DLV-11 (CSR 176500, vector 300, priority 5) >> for network access. Add the following lines to your OpenSIMH .ini file: >> >> SET CPU 11/23 >> SET DLI ENA LINES=1 >> SET DLO0 DATASET 8B >> ATTACH DLI LINE=0,SPEED=115200,CONNECT=<IP ADDR>:<PORT>;NOTELNET >> >> If you are attaching to PyDECDnet, the associated configuration line would >> be: >> >> circuit dl-0 DDCMP --mode tcp --local-port <PORT> >> >> where <IP ADDR> and <PORT> need to be set according to your network. >> >> The network configuration is in a file called "CETAB.MAC". We can use CFE >> (Configuration File Editor) to change the node name and address (in this case >> to node name RT11 at address 111): >> >> .R CFE >> File name <SY:CETAB.MAC>: >> CFE>LIST EXEC >> >> Executor permanent characteristics as of 00:00 >> >> Identification = ERC PDP-11/23 >> Name = ERC23, Address = 124 >> Host = 124, Maximum links = 4 >> >> CFE>DEFINE EXECUTOR NAME RT11 ADDRESS 111 HOST 111 IDENT "RT11 11/23" >> CFE>LIST EXEC >> >> Executor permanent characteristics as of 00:01 >> >> Identification = RT11 11/23 >> Name = RT11, Address = 111 >> Host = 111, Maximum links = 4 >> >> CFE>DEFINE NODE 112 NAME REMOTE >> CFE>EXIT >> >> The last DEFINE command defines nodes in your DECnet network so you can >> connect >> to them. >> >> To load DECnet: >> >> .ASSIGN SY NT >> .R NCP >> NCP>SET SYSTEM >> NCP>SET EXECUTOR STATE ON >> NCP>SHO EXEC >> >> Node volatile summary as of 00:00 >> >> Executor node = 111 (RT11) >> >> State = On, Identification = RT11 11/23 >> >> NCP>EXIT >> >> >> If you want to allow incoming connections run NJS (Network Job Spawner): >> >> .R NJS >> >> ?NJS-I-Network Job Spawner Active >> >> and then it will report each program activation. >> >> >> The following programs are available: >> >> NCP - Network Control Program >> NFT - Network File Transfer >> TLK - Interactive talk with another (remote) terminal >> RMT - Remote terminal (RSX) >> RVT - Remote terminal (VMS) >> CED - Dumps internal DECnet data structures (/AL dumps >> everything) >> >> The following servers are available: >> >> NML - Network Management Listener (use with NCP) >> FAL - File Access Listener (use with NFT) >> LOOPER - Loop testing (use with NCP LOOP NODE name) >>
