10 Mar
2026
10 Mar
'26
9:52 a.m.
Sp 176500/300.
On March 10, 2026 2:49:06 PM GMT, johnforecast--- via cctalk <cctalk(a)classiccmp.org>
wrote:
As configured it will use the “Terminal 1” port on a
PDT-11/150. I doubt it will support sync serial - it looks like the standard DL-11 driver
from RSX.
John.
On Mar 10, 2026, at 4:37 AM, Christopher Zach via
cctalk <cctalk(a)classiccmp.org> wrote:
Thank you! This is so cool, I want to get decnet running on my pdt11/150 and connect it
to my rsx11 system.
I wonder if it can support sync serial options so I can run it at 19200 baud on the
"modem" port on the pdt.
On March 9, 2026 4:18:55 PM GMT+01:00, johnforecast--- via cctalk
<cctalk(a)classiccmp.org> wrote:
> 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)
>