RSX-11M trouble

Mark Matlock mark at
Fri Apr 1 22:45:21 CDT 2016

> The SYSVMR.CMD shows that the Indirect Command Processor is named ICP.TSK.
> Sadly, ICP.TSK is one of the four tasks that have read issues...
> I need another info: BAD is destructive or not destructive?
BAD is destructive to the data on the disk!
If there are only four tasks that have read issues you may be able to move just those 
tasks over from a good version of RSX-11M with Kermit which you mentioned you had.

> Here I am!
> RSX-11M V4.2 BL38B
> I have two RX50 disk units and Kermit.
> 512kb and one RD51 fixed disk.
> I planned to archive separately every [*,*] and image the disks.
> I tried and can write back and read RX50 disks with a properly setup PC.
> I need only RSX-11M installation disks images but I'm confident they can be found somewhere on the net.
> I'll give a look to BRU...

A RD51 drive holds about 10 MB which is about the minimum for a RSX-11M system. The RX50
disks could load a version of Micro RSX which was a pre-GENed RSX-11M system. I used it
one time to recover a non-bootable RSX system disk where someone deleted the RSX11M.SYS
file that the boot block pointed to. I have not seem those RX50 images of Micro RSX on the internet so far.

Since you can read and write the RX50 disks with a PC. Get a copy of PUTR from John Wilson Dbit site

to be able to write RX50s in RT-11 which can be read in RSX-11M with FLX. Then get a copy of Simh
from the GitHub:

Once you have a working Simh PDP-11 emulator (e.g. pdp11.exe) then get a bootable baseline RSX11M disk image (Note: this disk image is actually RSX11M V4.8

The Simh will need a configuration file (e.g. sim.ini) that describes the PDP-11 system it is emulating like this:

sim> do sim.ini
set console log=./console.log
set cpu 11/23, 256K
set cpu idle
set tto 8b
set rq0 rd54
attach rq0 rsxm70.dsk
sim>show rq
sim> show rq
RQ	address=17772150-17772153, no vector, RQDX3, 4 units
  RQ0	159MB, not attached, write enabled
	RD54, autosize, SIMH format
  RQ1	159MB, not attached, write enabled
	RD54, autosize, SIMH format
  RQ2	159MB, not attached, write enabled
	RD54, autosize, SIMH format
  RQ3	800KB, not attached, write enabled
	RX50, autosize, SIMH format
sim> b rq0
and it will boot RSX11M where

this will bring up a baseline RSX11M system. DU3 should be a virtual RX50 that will create a disk image that can be read with
PUTR and moved to a real RX50 or you could use Linux DD to image the RX50.

At any rate the emulated RSX11M system will have the tasks that should be compatible on your real PDP-11. You might also
be able to kermit from the simulated to the physical PDP-11.

At any rate having a virtual RSX11M system to experiment with will help you a great deal in getting your real system running.
If this is too complicated, I could try sending you an RX50 disk image with the tasks you need, but I only have RSX11M V4.8 
(I mostly use RSX11M+ V4.6) handy so we'd have to try those .TSKs to see if they might work. 

> Well, let me understand better...
> 1) VFY reports errors on some files (-4 and -101), but ELI DU0:/SH
> reports no soft or hard errors.
> I have a defective disk or the file system is broken?
> 2) No ICX.TSK. Only ICP.TSK, (-4 and -101 errors with VFY)
> 3) I've found only tape images for RSX-11M. I have no tape unit. 

If you are not getting errors on the disk, then the disk is probably ok and the file
system has some corruption. Remember that an RSX11M system should be
shut down by running shut up to make sure all files are closed etc.


BRU can do disk to disk copies but with only one RD51 and no tape it won't help much.

In my RSX work I use a SCSI disk controller like a Emulex UC07 with the SCSI2SD
card that emulates unto 4 DU disks on one microSD card. This makes it very easy to move
large disk images from Simh on a PC to be bootable RSX disks on the PDP-11. It is
easy to back up and very reliable. The SCSI2SD card is only $65 but Qbus SCSI cards
are a bit pricey.

By the way which CPU is in the PDP-11, a 11/23?

Good Luck,

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