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

Microtech Dart microtechdart at gmail.com
Sun Nov 22 03:46:28 EST 2015


Bruce,

I am going over the LUN files in great detail, and I'm finding a pattern,
with some discrepancy.

Could you confirm one thing for me before I continue, please?

According to the chart you sent below, it appears that LUN0 and LUN1
overlap.  If LUN0 ends on *15,4,31 *and LU0 begins on *15,0,0 *isn't this
overlapping?  Could it be that LU1 begins on 16,0,0 ?

Could there be any other anomalies in this table?  I just want to confirm
before I hunt too much further.  Going through these files block-by-block
is fairly arduous.

Thanks for all your help on this!
-AJ

*LUN     CYL   HD  SEC*
*----    ---   --  ---*

*LUN 0:    0,   0,   0    disk start address*
*         15,   4,  31    disk end   address*

*LUN 1:   15,   0,   0*
*        111,   4,  31*

*LUN 2:  112,   0,   0*
*        223,   4,  31*

*LUN3:   224,   0,   0*
*        335,   4,  31*

*LUN4:   336,   0,   0*
*        441,   4,  31*



On Wed, Nov 18, 2015 at 11:29 AM, Bruce Ray <Bruce at wild-hare.com> wrote:

> G'day AJ -
>
> There is only one program on the 'MinicomDiskUtility.bin' file - there is
> no data beyond the 8KB (the file size is only). There is no "filemark" or
> other pseudo-/meta- data that I detect in the file, just a single stream of
> 4096 words (as appropriate for the DG word-oriented architecture
> [big-endian]).  What other file(s) am I missing?
>
>
> Regardless, dissecting and running the utility reveals further program
> assumptions:
>
> The 40 MB disk drive has a geometry of 442 cylinders, 5 heads, 32
> sectors/track (head).
>
> The IRIS logical unit to physical disk address assignments are:
>
>
> LUN     CYL   HD  SEC
> ----    ---   --  ---
>
> LUN 0:    0,   0,   0    disk start address
>          15,   4,  31    disk end   address
>
> LUN 1:   15,   0,   0
>         111,   4,  31
>
> LUN 2:  112,   0,   0
>         223,   4,  31
>
> LUN3:   224,   0,   0
>         335,   4,  31
>
> LUN4:   336,   0,   0
>         441,   4,  31
>
>
> Total disk formatted size:  36,308,640 bytes
>
> Data is transferred to/from the disk to the tape drive in 4KB records
> during backup/restore operations.
>
> Only logical units 0, 1 and 2 can fit on a tape; a second tape was
> required for backing up logical units 3 and 4.
>
> Next step: obtain data files that contain the LUNx information...
>
>
> Bruce
>
>
>
> On 11/18/2015 2:21 AM, Microtech Dart wrote:
>
>> Bruce!  This is very exciting...you actually RAN the file!  I'm so
>> excited to know that this is possible.
>>
>> I received the screen shots in my MightyFrame email, thank you for those.
>>
>> Most of what you are talking about is still Greek to me, but I'll catch
>> up.
>>
>> "The tape file itself needs to be created in the SimH tape if it is to
>> be used with the default SimH tape driver. The QIC format may exist as a
>> single large data record of 16,384 bytes, or of multiple 512-byte
>> records followed by a file mark. (I can not tell its original format
>> given only the .bin file to work with.)"
>>
>> OK, so I know exactly how the data format was written to this tape.
>>   (For detail on the format itself, I outline it in exhaustive detail on
>> this page: http://bit.ly/1RhcdK2  )  The format is neither QIC-11 nor
>> QIC-24, but some very weird format that I've traced back to a specific
>> model of Kennedy QIC tape drive.
>>
>> The Minicom Disk Utility file that you ran was in one single block of
>> data, which was 8192 bytes long.  It was, as you indicate, the very
>> first block of data on the tape.  This block was followed by a filemark.
>>
>> The next block after the filemark was also 8192 bytes (with nearly, but
>> not exactly the same content as this Minicom utility file), but
>> thereafter, every other block on the tape was only 4096 bytes long, as
>> was all of the other blocks on the entire tape. (Notice that this is
>> either 8 or 16 times the length of a "normal" QIC-11 or QIC-24 512-byte
>> data block).
>>
>> This tape was marked "LU0, position 1; LU1, position 2; LU2, position
>> 3", so I expect this tape to have those 3 logical units on it.
>>
>> It seems that there are 3 more filemarks on this tape (if I counted
>> correctly), so then this tape has 4 files, one file for the Minicom Disk
>> Utility, and one file for each of the Logical Units.
>>
>> I can tell you right now that the LU0 file (if that is really what it
>> is), is 1,331,200 bytes, or exactly 1,300 Mb (if I did the math right).
>> The other 2 files I need to study more deeply to tell for sure, as they
>> span the tape tracks, and are more complicated for me to assemble.
>>
>> Would it be best to just work with those as files, or do they need to be
>> kept in their original "Kennedy" block formation, or another block
>> formation or format?
>>
>> Bruce, it is my goal to restore these tapes, and get a machine to run
>> again as close as possible to the way it would have when these backups
>> were made.  With your ability to run the Minicom file, it gives me great
>> hope that this is possible.
>>
>> What would be my next steps to get myself working on a system that has
>> the capability of doing this?  I'm open to whether that is SimH,
>> reNOVAte, or other.
>>
>> Thank you again, Bruce, this is very exciting news!
>>
>> -AJ
>>
>>
>>
>>
>>
>> On Wed, Nov 18, 2015 at 1:42 AM, Bruce Ray <Bruce at wild-hare.com
>> <mailto:Bruce at wild-hare.com>> wrote:
>>
>>     G'day AJ -
>>
>>     Briefly...
>>
>>     The tape contains a disk/tape backup/restore utility that is
>>     somewhat representative of those used with Point 4, and other
>>     3rd-party DG lookalike systems. It is a stand-alone utility that is
>>     bootable if it exists as the first record of the first file of a mag
>>     tape or cartridge.
>>
>>     The usual procedure is to bootstrap the tape using the Nova APL
>>     function (or just toggling in simple 2-instruction 'fat-finger'
>>     program).  Once the program is read into memory, it starts execution
>>     and displays its introductory message.  At this point another
>>     tape/cartridge may be loaded onto the tape drive for backup or
>>     restore purposes.
>>
>>     I used our reNOVAte software for doing my investigations rather than
>>     SimH due to convenience, and was able to run the program and
>>     exercise its various functions. (Screen shots are attached.)
>>
>>     This particular utility is very specific regarding the type of disk
>>     drive and IRIS logical units it supports.
>>
>>     The utility assumes two devices exist: a tape controller using
>>     device code <022> and a disk controller using device code <027>. The
>>     tape controller may or may not perform QIC to DG-style file handling
>>     emulation since the original tape is not available to me.
>>     The disk controller appears to use the standard DG "Zebra"
>>     controller (Model 6060/6061/6067) programming model. However, it
>>     assumes a non-standard disk geometry of 16 cylinders, 5 heads, and
>>     32 sectors.
>>
>>     The tape file itself needs to be created in the SimH tape if it is
>>     to be used with the default SimH tape driver. The QIC format may
>>     exist as a single large data record of 16,384 bytes, or of multiple
>>     512-byte records followed by a file mark. (I can not tell its
>>     original format given only the .bin file to work with.)
>>
>>     The utility also makes assumptions about tape read timing and CPU
>>     instruction execution speed. Horrible programming technique, but
>>     unfortunately not uncommon practice.  Any such timing dependencies
>>     must be found and compensated for in the device driver or
>>     instruction emulation.
>>
>>     Since there is no disk backup tape to load onto the disk, I used
>>     dummy disk data for testing the disk-to-tape and tape-to-disk
>>     functions.  Real backup tape(s) would obviously be needed to restore
>>     the original system.
>>
>>
>>     Bruce
>>
>>
>>
>>     On 11/14/2015 3:35 PM, Microtech Dart wrote:
>>
>>         Thank you, Dell, and Sandy Strain, both of your responses were
>>         EXTREMELY
>>         helpful to me, and these all worked!
>>
>>         Do either of you have any additional thoughts about how I could
>> make
>>         what I believe to be a bootable file (extracted from a
>>         Microtech/Point4
>>         QIC tape) into a bootable device for the Nova?
>>
>>         I'll start with the Minicom Disk To Tape Utility:
>>
>>
>> http://microtechm1.blogspot.com/2015/09/minicom-disk-to-tape-copy-utility.html
>>
>>         I've attached a .zip of the binary file that I extracted from
>>         this tape
>>         for reference.  It's very small, so I zipped it up only so that
>> the
>>         emailing process didn't interfere with or reject it.
>>
>>         Thanks, all!
>>
>>         -AJ
>>
>>         On Sat, Nov 14, 2015 at 7:23 AM, Dell Setzer <dsetzer at panix.com
>>         <mailto:dsetzer at panix.com>
>>         <mailto:dsetzer at panix.com <mailto:dsetzer at panix.com>>> wrote:
>>
>>              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 <http://LITMACS.SR> <http://LITMACS.SR>
>>         OSID.SR <http://OSID.SR> <http://OSID.SR>
>>         NSID.SR <http://NSID.SR> <http://NSID.SR>
>>         PARS.SR <http://PARS.SR> <http://PARS.SR>
>>         ALMSPD.SR <http://ALMSPD.SR> <http://ALMSPD.SR>
>>                 <etc.>
>>              R
>>              dump/v mt0:1 -.sv
>>         BURST.SV <http://BURST.SV> <http://BURST.SV>
>>         INITIALIZE.SV <http://INITIALIZE.SV> <http://INITIALIZE.SV>
>>         SEDIT.SV <http://SEDIT.SV> <http://SEDIT.SV>
>>         MACXR.SV <http://MACXR.SV> <http://MACXR.SV>
>>         EDIT.SV <http://EDIT.SV> <http://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 <http://LITMACS.SR> <http://LITMACS.SR>
>>         10/20/83
>>         OSID.SR <http://OSID.SR> <http://OSID.SR>               01/10/84
>>         NSID.SR <http://NSID.SR> <http://NSID.SR>               10/20/83
>>         PARS.SR <http://PARS.SR> <http://PARS.SR>               01/31/85
>>                 <etc>
>>              R
>>              load/n mt0:1
>>         BURST.SV <http://BURST.SV> <http://BURST.SV>
>> 05/09/85
>>         INITIALIZE.SV <http://INITIALIZE.SV> <http://INITIALIZE.SV>
>>             05/02/85
>>         SEDIT.SV <http://SEDIT.SV> <http://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
>>
>>
>>
>>
>>         --
>>
>>         Thanks,
>>         -AJ
>>         http://MicrotechM1.blogspot.com
>>
>>
>>         _______________________________________________
>>         Simh mailing list
>>         Simh at trailing-edge.com <mailto:Simh at trailing-edge.com>
>>         http://mailman.trailing-edge.com/mailman/listinfo/simh
>>
>>     _______________________________________________
>>     Simh mailing list
>>     Simh at trailing-edge.com <mailto:Simh at trailing-edge.com>
>>     http://mailman.trailing-edge.com/mailman/listinfo/simh
>>
>>
>>
>>
>> --
>>
>> Thanks,
>> -AJ
>> http://MicrotechM1.blogspot.com
>>
>>
>> _______________________________________________
>> Simh mailing list
>> Simh at trailing-edge.com
>> http://mailman.trailing-edge.com/mailman/listinfo/simh
>>
>> _______________________________________________
> Simh mailing list
> Simh at trailing-edge.com
> http://mailman.trailing-edge.com/mailman/listinfo/simh




-- 

Thanks,
-AJ
http://MicrotechM1.blogspot.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.trailing-edge.com/pipermail/simh/attachments/20151122/1564520a/attachment-0001.html>


More information about the Simh mailing list