[Simh] DG Nova booting from another file or "device"?

[Dell Setzer]

It's actually pretty easy. After booting RDOS, press ^E to return to the 
sim> prompt. Then, attach a host file to the MTA0 unit. If you give a host 
filename that doesn't yet exist, SIMH will create an empty tape file and 
attach it to MTA0:

sim> attach mta0 testtape.tap
MTA: creating new file
sim>

Then, give the simh G command to return to RDOS and init/f the MT0 tape 
unit. Note that at the sim> prompt, the unit is called "MTA0" (or MTA1, 
MTA2, etc), while in RDOS the unit is called "MT0" (or MT1, MT2, etc):

sim> g
<presss return to get the RDOS prompt again>
R
init/f mt0
CONFIRM? <press Y to confirm>
R

Now you can dump or copy files to the MT0 device:
dump/v mt0:0 -.sr
   LITMACS.SR
   OSID.SR
   NSID.SR
   PARS.SR
   ALMSPD.SR
   <etc.>
R
dump/v mt0:1 -.sv
   BURST.SV
   INITIALIZE.SV
   SEDIT.SV
   MACXR.SV
   EDIT.SV
   <etc.>
R
release mt0
R

After releaseing the tape, press ^E again to get to the sim> prompt and 
detach the tape file:
^E
sim> detach mta0
sim>
Now you can inspect the testtape.tap tape image.

Attaching an existing tape file is similar, except that at the RDOS prompt 
you'd do INIT rather than INIT/F:

sim> attach mta0 testtape.tap
sim> g
R
init mt0
R
load/n mt0:0
   LITMACS.SR            10/20/83
   OSID.SR               01/10/84
   NSID.SR               10/20/83
   PARS.SR               01/31/85
   <etc>
R
load/n mt0:1
   BURST.SV              05/09/85
   INITIALIZE.SV         05/02/85
   SEDIT.SV              05/02/85
   <etc>
R
release mt0
R

Hope this helps,
...dell

On Sat, 14 Nov 2015, Microtech Dart wrote:

> Hi, I am completely new here, although I recognize the names of several who
> post here.
>
> I am trying to resurrect an extinct Microtech machine from 1982, which
> likely used the Point 4 processor, and the SimH DG Nova simulator *should*
> be compatible with the Point 4.
>
> I'm running the NOVA simulator now, with:
>
> NOVA simulator V4.0-0 Beta        git commit id: 3be5125d
> sim> ATTACH DKP0 *rdos_d31.dsk*
> sim> set tti dasher
> sim> boot DKP0
>
> I'm teaching myself RDOS now with the RDOS_Command_Line_Interpreter Manual.
> <http://www.mirrorservice.org/sites/www.bitsavers.org/pdf/dg/software/rdos/093-000109-01_RDOS_Command_Line_Interpreter.pdf>
>
> Would anybody here be able to suggest some methods by which I could
> *create* a magnetic tape device on this SimH Nova simulator, and how I
> might write some files to that?
>
> I think that would be an excellent experiment for me to attempt.  Then I
> can inspect the binary file in a hex editor, and see what it looks like,
> then compare to the binaries I've pulled off my Microtech/Point 4 tapes.
>
> -- 
>
> Thanks,
> -AJ
> http://MicrotechM1.blogspot.com
>