Noting that some of the available software requires at least MicroVMS 4.5 i thought i would just create a new installation image to install of the physical machine.
This can be done using simh with the benefit of progressive backups. V4.7 seemed like the obvious candidate given that it seems to be well-supported by the VAX/VMS community.
There is a gnarly issue in that the available distribution seems to only be available in TK50 tape format and the Microvax I (even the emulated simh MicroVAX I) does not have a tape drive.
The solution suggested by https://microvax2.org, is to install on an emulated Microvax II and then migrate to the Microvax I. This can be done in one step by doing a standalone backup and restore, or in two steps by moving the disk image to the Microvax I emulation, adjusting it, and then using the standalone backup/restore to migrate to the physical device.
This last step, using the RQDX1 disk controller card and RX50 disk drive in the physical Microvax I, requires about 75 400kB floppy disks. It is a process that grows old quickly!
I opted for the two-step process so i could do some testing on the emulated MicroVAX I before doing the huge backup/restore.
Noting also that the physical Microvax has a 30MB RD52 hard disk and the RQDX1 disk controller i changed the MicroVAX II configuration to use the smaller RD52 drive rather than the RD54.
The migration from MicroVax II to MicroVAX I seemed to work ok. I ran sysgen in the hope that it would tidy up any residual issues.
$ run sys$system:sysgen
SYSGEN> AUTOCONFIGURE ALL
SYSGEN> EXIT
I also found that disk space with the RD52 is very tight. I reduced the pagefile.sys and swapfile.sys files to 4000 blocks (2MB) each and bravely ran a purge over the entire disk.
$ sh dev
Device Device Error Volume Free Trans Mnt
Name Status Count Label Blocks Count Cnt
DUA0: Mounted 0 MICROVMS 7360 25 1
DUA1: Online 0
DUA2: Online 0
DUA3: Mounted alloc 0 SHARE2 1160898 1 1
Device Device Error
Name Status Count
OPA0: Online 0
RTA0: Offline 0
RTB0: Offline 0
TTA0: Online 0
TTA1: Online 0
TTA2: Online 0
TTA3: Online 0
Device Device Error
Name Status Count
PUA0: Online 1
XQA0: Online 0
XQA1: Online 0$ sh mem
System Memory Resources on 6-MAY-2026 15:26:40.61
Physical Memory Usage (pages): Total Free In Use Modified
Main Memory (2.00Mb) 4096 1659 2166 271
Slot Usage (slots): Total Free Resident Swapped
Process Entry Slots 27 20 7 0
Balance Set Slots 24 19 5 0
Fixed-Size Pool Areas (packets): Total Free In Use Size
Small Packet (SRP) List 101 21 80 96
I/O Request Packet (IRP) List 68 6 62 208
Large Packet (LRP) List 11 1 10 1584
Dynamic Memory Usage (bytes): Total Free In Use Largest
Nonpaged Dynamic Memory 242176 34416 207760 30224
Paged Dynamic Memory 138240 56528 81712 55520
Paging File Usage (pages): Free In Use Total
DISK$MICROVMS:[SYS0.SYSEXE]SWAPFILE.SYS 7040 1056 8096
DISK$MICROVMS:[SYS0.SYSEXE]PAGEFILE.SYS 12628 164 12792
Of the physical pages in use, 1508 pages are permanently allocated to VMS.
$ run sys$system:sysgen
SYSGEN> CREATE DISK$MICROVMS:[SYS0.SYSEXE]SWAPFILE.SYS /SIZE=4000
%SYSGEN-I-CREATED, DISK$MICROVMS:[SYS0.SYSEXE]SWAPFILE.SYS;2 created
SYSGEN> CREATE DISK$MICROVMS:[SYS0.SYSEXE]PAGEFILE.SYS /SIZE=4000
%SYSTEM-W-DEVICEFULL, device full - allocation failure
SYSGEN> EXIT
$ delete DISK$MICROVMS:[SYS0.SYSEXE]SWAPFILE.SYS;1
$ run sys$system:sysgen
SYSGEN> CREATE DISK$MICROVMS:[SYS0.SYSEXE]PAGEFILE.SYS /SIZE=4000
%SYSGEN-I-CREATED, DISK$MICROVMS:[SYS0.SYSEXE]PAGEFILE.SYS;2 created
SYSGEN> EXIT
$ delete DISK$MICROVMS:[SYS0.SYSEXE]PAGEFILE.SYS;1
$ sh dev
Device Device Error Volume Free Trans Mnt
Name Status Count Label Blocks Count Cnt
DUA0: Mounted 0 MICROVMS 20260 25 1
DUA1: Online 0
DUA2: Online 0
DUA3: Mounted alloc 0 SHARE2 1160898 1 1
Device Device Error
Name Status Count
OPA0: Online 0
RTA0: Offline 0
RTB0: Offline 0
TTA0: Online 0
TTA1: Online 0
TTA2: Online 0
TTA3: Online 0
Device Device Error
Name Status Count
PUA0: Online 1
XQA0: Online 0
XQA1: Online 0
$ dir sys$system:*.sys /size
Directory SYS$SYSROOT:[SYSEXE]
PAGEFILE.SYS;2 4000
SWAPFILE.SYS;2 4000
Total of 2 files, 8000 blocks.
$ dir sys$system:*.sys;* /size
Directory SYS$SYSROOT:[SYSEXE]
PAGEFILE.SYS;2 4000
SWAPFILE.SYS;2 4000
$ sh dev
Device Device Error Volume Free Trans Mnt
Name Status Count Label Blocks Count Cnt
DUA0: Mounted 0 MICROVMS 23178 25 1
DUA1: Online 0
DUA2: Online 0
DUA3: Mounted alloc 0 SHARE2 1160898 1 1
Device Device Error
Name Status Count
OPA0: Online 0
RTA0: Offline 0
RTB0: Offline 0
TTA0: Online 0
TTA1: Online 0
TTA2: Online 0
TTA3: Online 0
Device Device Error
Name Status Count
PUA0: Online 1
XQA0: Online 0
XQA1: Online 0Hopefully, the 10MB or so that is now available is enough to install some languages.
A better solution maybe a second hard drive, but that will involve a very expensive solid state option. An alternative may be to network with an emulated server. That would be a steep learning curve, and it will require a significant investment in an ethernet card.
This gave me a basic working image for MicroVMS 4.7 on the MicroVAX I.
I started by installing the 4 languages that i had chosen: pascal, basic, fortran and C. These were installed automatically on the 8650 emulation so i used following extract from the 8650 installation log as a guide.
$ @sys$update:vmsinstal basic032 MTA0:
VAX/VMS Software Product Installation Procedure V4.7
It is 3-MAY-1998 at 20:01.
Enter a question mark (?) at any time for help.
* Are you satisfied with the backup of your system disk [YES]? yes
Please mount the first volume of the set on MTA0:.
* Are you ready? yes
%MOUNT-I-MOUNTED, BASIC mounted on _795VAX$MTA0:
The following products will be processed:
BASIC V3.2
Beginning installation of BASIC V3.2 at 20:01
%VMSINSTAL-I-RESTORE, Restoring product saveset A...
%VMSINSTAL-I-RELMOVED, The products release notes have been successfully moved to SYS$HELP.
VAX BASIC V3.2 Installation Procedure
There are three possible installation options. They are described
as follows:
1) Perform a normal installation of BASIC.
2) Install VAX/VMS system definitions text library only (10-45 minutes).
3) Obtain a copy of the BASIC message text for modification.
* Which option do you want to use [1]: 1
* Do you want to install the BASIC HELP files [YES]? yes
* Do you want to install the VAX/VMS system definitions [YES]? yes
* Do you want to install the sample graphics programs [YES]? yes
* Do you want to purge files replaced by this installation [YES]? yes
%VMSINSTAL-I-RESTORE, Restoring product saveset B...
************************************************************************
If you have VAX GKS V2.0 or later on your system, VAX BASIC V3.2 allows
you to use graphics language statements. The procedure:
SYS$UPDATE:BASIC$GRAPHICS_IVP.COM
will verify that VAX BASIC graphics capabilities work on your system.
You must execute this procedure on a terminal with graphics capabilities.
************************************************************************
%VMSINSTAL-I-INSHELP, Installing BASIC Help files
%VMSINSTAL-I-RESTORE, Restoring product saveset C...
%VMSINSTAL-I-INSSTARLET, Installing BASIC system definitions
%VMSINSTAL-I-INSSTARLT1, Requires approximately 10 to 45 minutes
%VMSINSTAL-I-RESTORE, Restoring product saveset D...
%VMSINSTAL-I-INSSAMPLE, Installing sample programs and PICTURE libraries
%VMSINSTAL-I-RESTORE, Restoring product saveset E...
%VMSINSTAL-I-RESTORE, Restoring product saveset F...
%VMSINSTAL-I-SYSDISK, This product creates system disk directory VMI$ROOT:[SYSHLP.EXAMPLES.BASIC].
*********************************************************************
A number of sample programs demonstrating BASIC graphics statements
have been copied to [SYSHLP.EXAMPLES.BASIC].
Read [SYSHLP.EXAMPLES.BASIC]BASIC_EXAMPLES.TXT for information on the
sample programs provided.
*********************************************************************
%VMSINSTAL-I-MOVEFILES, Files will now be moved to their target directories...
%VMSINSTAL-I-RUNIVP, Executing installation verification procedure
%VMSINSTAL-I-IVPSUCCESS, VAX BASIC V3.2 Installation test PASSED
Installation of BASIC V3.2 completed at 20:01
********************************************
VMSINSTAL procedure done at 20:01
$ @sys$update:vmsinstal pascal037,passtr034 MTA0:
VAX/VMS Software Product Installation Procedure V4.7
It is 3-MAY-1998 at 20:01.
Enter a question mark (?) at any time for help.
* Are you satisfied with the backup of your system disk [YES]? yes
Please mount the first volume of the set on MTA0:.
* Are you ready? yes
%MOUNT-I-MOUNTED, PASCAL mounted on _795VAX$MTA0:
The following products will be processed:
PASCAL V3.7
PASSTR V3.4
Beginning installation of PASCAL V3.7 at 20:01
%VMSINSTAL-I-RESTORE, Restoring product saveset A...
%VMSINSTAL-I-RELMOVED, The products release notes have been successfully moved to SYS$HELP.
*-----------------------------------------*
* Installation Command Procedure for *
* VAX PASCAL V3.7 *
*-----------------------------------------*
* Do you want to purge files replaced by this installation [YES]? yes
This kit contains a file summarizing the new features, changes,
restrictions, and compatibility issues in this release of VAX
PASCAL. This file is named PASCAL037.RELEASE_NOTES and is
placed in SYS$HELP:.
This file contains information valuable to VAX PASCAL programmers.
Please inform your user community of this file's existence.
All questions regarding the installation have now been asked.
The installation of VAX PASCAL V3.7 will now continue for
approximately 5 to 120 minutes depending on your configuration.
%VMSINSTAL-I-RESTORE, Restoring product saveset B...
Your VMS system will now be updated to include the following new and
modified files:
SYS$HELP:HELPLIB.HLB [modified]
SYS$HELP:PASCAL037.RELEASE_NOTES [new]
SYS$LIBRARY:DCLTABLES.EXE [modified]
SYS$LIBRARY:LIBDEF.PAS [new]
SYS$LIBRARY:MTHDEF.PAS [new]
SYS$LIBRARY:PASDEF.PAS [new]
SYS$LIBRARY:PASSTATUS.PAS [new]
SYS$LIBRARY:SIGDEF.PAS [new]
SYS$MESSAGE:PASCALER1.EXE [new]
SYS$MESSAGE:PASCALER2.EXE [new]
SYS$SYSTEM:PASCAL.EXE [new]
%VMSINSTAL-I-MOVEFILES, Files will now be moved to their target directories...
*-----------------------------------------*
* Installation Verification Procedure for *
* VAX PASCAL V3.7 *
*-----------------------------------------*
** Successful Installation of VAX Pascal V3.7-254 on 3-May-1998 at 20:01 **
Installation of PASCAL V3.7 completed at 20:01
Beginning installation of PASSTR V3.4 at 20:01
%VMSINSTAL-I-RESTORE, Restoring product saveset A...
%VMSINSTAL-I-RELMOVED, The products release notes have been successfully moved to SYS$HELP.
*-----------------------------------------------*
* Installation Command Procedure for VAX PASCAL *
* libraries STARLET.PAS and STARLET.PEN *
*-----------------------------------------------*
* Do you want to purge files replaced by this installation [YES]? yes
This kit contains a file summarizing the new features, changes,
restrictions, and compatibility issues in this release of the
VAX PASCAL STARLET library. This file is named
PASSTR034.RELEASE_NOTES and will be placed in SYS$HELP:.
This file contains information valuable to VAX PASCAL programmers.
Please inform your user community of this file's existence.
All questions regarding the installation have now been asked.
The installation of VAX PASCAL STARLET.PAS and STARLET.PEN
will now continue for approximately 20 to 25 minutes.
Your VMS system will now be updated to include the following new files.
SYS$HELP:PASSTR034.RELEASE_NOTES
SYS$LIBRARY:STARLET.PAS
SYS$LIBRARY:STARLET.PEN
%VMSINSTAL-I-MOVEFILES, Files will now be moved to their target directories...
*-----------------------------------------------*
* Installation Verification Procedure for *
* VAX PASCAL STARLET V3.4 *
*-----------------------------------------------*
** Successful Installation of VAX PASCAL STARLET libraries **
Installation of PASSTR V3.4 completed at 20:01
VMSINSTAL procedure done at 20:01
*****************************************************************
$ @sys$update:vmsinstal fort048,fhlp048 MTA0:
VAX/VMS Software Product Installation Procedure V4.7
It is 3-MAY-1998 at 20:02.
Enter a question mark (?) at any time for help.
* Are you satisfied with the backup of your system disk [YES]? yes
Please mount the first volume of the set on MTA0:.
* Are you ready? yes
%MOUNT-I-MOUNTED, FORT mounted on _795VAX$MTA0:
The following products will be processed:
FHLP V4.8
FORT V4.8
Beginning installation of FHLP V4.8 at 20:02
%VMSINSTAL-I-RESTORE, Restoring product saveset A...
+-------------------------------------------------------+
| Installation of VAX FORTRAN V4 |
| FORTRAN HELP |
+-------------------------------------------------------+
This kit contains two separate HELP files, a large
version (approximately 600 blocks) including information
on FORTRAN language features, and a smaller version
(approximately 100 blocks) describing only the FORTRAN
command. Both versions contain on-line release notes.
* Do you want to install the larger version of FORTRAN HELP [YES]? yes
Your VMS system will now be updated to include the
following new and modified file(s):
SYS$HELP:HELPLIB.HLB [modified]
%VMSINSTAL-I-MOVEFILES, Files will now be moved to their target directories...
Installation of FHLP V4.8 completed at 20:02
Beginning installation of FORT V4.8 at 20:02
%VMSINSTAL-I-RESTORE, Restoring product saveset A...
%VMSINSTAL-I-REWIND, The tape will be rewound to try again.
* Do you want to purge files replaced by this installation [YES]? yes
* Do you wish to have the VAX FORTRAN compiler installed [YES]? yes
+-------------------------------------------------------+
| Installation of VAX FORTRAN V4 |
| Compiler |
+-------------------------------------------------------+
This kit contains an Installation Verification Procedure
to verify the correct installation of the VAX FORTRAN
compiler.
* Do you want to run the IVP after the installation [YES]? yes
This kit contains a file, VAXFORUPD.MEM, summarizing the
changes made to the VAX FORTRAN compiler since its last
release.
* How many copies would you like to print [0]: 0
A new FORSYSDEF.TLB is available with this installation.
In order to build your FORSYSDEF library, this procedure
requires at least 5500 blocks of available disk space,
most of which is used for temporary work files. The
FORSYSDEF library itself will take approximately 1500
blocks of disk space upon completion of this procedure
and will be placed in your SYS$LIBRARY area.
Note
Before installing the kit, be sure to have read section
1.5.1.1, UPDATING FORSYSDEF. It addresses the question
of when a new FORSYSDEF.TLB should be built.
* Do you wish to build a new FORSYSDEF.TLB [NO]? yes
Building FORSYSDEF. This should take about 20 minutes.
Your VMS system will now be updated to include the
following new and modified file(s):
SYS$SYSTEM:FORTRAN.EXE [new]
SYS$MESSAGE:FORTERR1.EXE [new]
SYS$MESSAGE:FORTERR2.EXE [new]
SYS$LIBRARY:FORTV4CLD.CLD [new]
SYS$TEST:FORTTEST.COM [new]
SYS$TEST:FORSYSDEFTST.COM [new]
SYS$LIBRARY:DCLTABLES.EXE [modified]
SYS$UPDATE:VAXFORUPD.MEM [new]
SYS$LIBRARY:FORSYSDEF.TLB [new]
%VMSINSTAL-I-MOVEFILES, Files will now be moved to their target directories...
+-------------------------------------------------------+
| Verification Command Procedure for |
| VAX FORTRAN |
+-------------------------------------------------------+
VAX FORTRAN V4.8-276 TEST PASSED
Installation of FORT V4.8 completed at 20:02
VMSINSTAL procedure done at 20:02
*******************************************************************************
$ @sys$update:vmsinstal vaxc024 MTA0:
VAX/VMS Software Product Installation Procedure V4.7
It is 3-MAY-1998 at 20:29.
Enter a question mark (?) at any time for help.
* Are you satisfied with the backup of your system disk [YES]? yes
Please mount the first volume of the set on MTA0:.
* Are you ready? yes
%MOUNT-I-MOUNTED, VAXC02 mounted on _795VAX$MTA0:
The following products will be processed:
VAXC V2.4
Beginning installation of VAXC V2.4 at 20:29
%VMSINSTAL-I-RESTORE, Restoring product saveset A...
%VMSINSTAL-I-RELMOVED, The products release notes have been successfully moved to SYS$HELP.
VAX C V2.4-026 Installation is commencing ...
* Do you want to run the IVP after the installation [YES]? no
* Do you want to purge files replaced by this installation [YES]? yes
* Do you want to extract .H files from the text library [YES]? yes
All the questions regarding the installation have
now been asked. The installation will now continue
for another 20 minutes.
%VMSINSTAL-I-RESTORE, Restoring product saveset B...
VAX C V2.4-026 : copying images, libraries and release notes.
VAX C V2.4-026 : extracting .H files.
A summary of the Software Performance Reports (SPRs) for this release
can be found in the file SYS$LIBRARY:VAXCSPR.DAT.
VAX C V2.4-026 Installation is completed.
Your VMS system will now be updated to include the following new
and modified files:
SYS$SYSTEM:VAXC.EXE [new]
SYS$LIBRARY:VAXCDEF.TLB [new]
SYS$LIBRARY:VAXCSPR.DAT [new]
SYS$MESSAGE:VAXCERR.EXE [new]
SYS$HELP:VAXC024.RELEASE_NOTES [new]
SYS$HELP:HELPLIB.HLB [modified]
SYS$LIBRARY:DCLTABLES.EXE [modified]
SYS$EXAMPLES:VAXCIVPP.C [new]
SYS$EXAMPLES:VAXCIVPC.C [new]
%VMSINSTAL-I-MOVEFILES, Files will now be moved to their target directories...
Installation of VAXC V2.4 completed at 20:29
VMSINSTAL procedure done at 20:29
VAX Basic and VAX Fortran played nicely right from the start. VAX pascal 3.7 failed test compilations with an internal error. VAX C 2.4 required configuration files to link – apparently because of the absence of a library in a particular format. I tried different versions but got the same result. The C issue does have a workaround; it seems that the VMSCRTL.OBJ file is absent from the system – perhaps because i am using MicroVMS rather than VMS.
$ create test.c
#include <stdio.h>
int main() {
printf("Hello, World! In C\n");
return 1;
}
Exit
$ cc test
$ link test
%LINK-W-NUDFSYMS, 2 undefined symbols:
%LINK-I-UDFSYM, C$MAIN
%LINK-I-UDFSYM, PRINTF
%LINK-W-USEUNDEF, undefined symbol C$MAIN referenced
in psect $CODE offset %X00000006
in module TEST file SYS$SYSROOT:[SYSMGR]TEST.OBJ;2
%LINK-W-USEUNDEF, undefined symbol PRINTF referenced
in psect $CODE offset %X00000013
in module TEST file SYS$SYSROOT:[SYSMGR]TEST.OBJ;2
$ create test.opt
SYS$LIBRARY:VAXCRTL/SHAREABLE
$ link test, test/options
$ run test
Hello, World! In C
The pascal issue was a mystery; i wondered if it was related to using a MicroVAX II installation on a MicroVAX I. I started reading about autogen and sysgen, and found a myriad of options described in what felt like a foreign language. It was overwhelming.
I am not proud, but i chose a 2026 solution in the form of AI – Gemini. It was not always correct, but i was able to paste in screen dumps which it used to make further corrections. In a couple of cases it broke the system, but that was ok because, working with an emulator, it is easy to take system disk snapshots and backtrack. Gemini gave quite specific instructions about what parameters to change and the process for updating the system. After a couple of hours it had seemingly resolved the issue with the pascal compiler internal issue.
The changes were as follows.
Comparing files working_params.dat and OLD_PARAMS.DAT
***** working_params.dat
!
VERSION="V4.7 "
CPUTYPE=7
SID=117441793
WSTYPE=0
MEMSIZE=4096
DISKSPEED=1
***** OLD_PARAMS.DAT
!
VERSION=" KG "
CPUTYPE=8
SID=134217728
WSTYPE=0
MEMSIZE=32768
DISKSPEED=1
*****
***** working_params.dat
DISKSIZE=60480
NUM_DISK=4
NUM_TAPE=0
NUM_SCOM=2
NUM_CARD=0
NUM_TERM=7
NUM_LP=0
***** OLD_PARAMS.DAT
DISKSIZE=60480
NUM_DISK=3
NUM_TAPE=0
NUM_SCOM=1
NUM_CARD=0
NUM_TERM=15
NUM_LP=0
*****
***** working_params.dat
NUM_REALTIME=0
NUM_BUS=1
NUM_MAILBOX=0
***** OLD_PARAMS.DAT
NUM_REALTIME=0
NUM_BUS=2
NUM_MAILBOX=0
*****
***** working_params.dat
NUM_CI=0
NUM_ETHERNET=2
NUM_SERVER=1
NUM_HOST=1
DRIVER_NPAGEDYN=93886
DECNET="true"
***** OLD_PARAMS.DAT
NUM_CI=0
NUM_ETHERNET=1
NUM_SERVER=2
NUM_HOST=1
DRIVER_NPAGEDYN=107671
DECNET="true"
*****
***** working_params.dat
PEDRIVER_LOADED="false"
! Parameters specified in SYS$SYSTEM:OLDSITE2.DAT
! Parameters specified in SYS$SYSTEM:OLDSITE3.DAT
ACP_SWAPFLGS=14
TIMEPROMPTWAIT=65535
! Parameters specified in SYS$SYSTEM:OLDSITE4.DAT
DISK_QUORUM=" "
SCSNODE=" "
TTY_DEFCHAR2=4106
! Parameters specified in SYS$SYSTEM:VMSPARAMS.DAT
***** OLD_PARAMS.DAT
PEDRIVER_LOADED="false"
! Parameters specified in SYS$SYSTEM:VMSPARAMS.DAT
*****
***** working_params.dat
VMS$ACP_DATACHECK=2
VMS$ACP_MAXREAD=6
VMS$ACP_SWAPFLGS=14
***** OLD_PARAMS.DAT
VMS$ACP_DATACHECK=2
VMS$ACP_MAXREAD=12
VMS$ACP_SWAPFLGS=14
*****
***** working_params.dat
VMS$ACP_SYSACC=4
VMS$DUMPFILE=0
VMS$GBLPAGES=1415
VMS$GBLSECTIONS=52
VMS$IJOBLIM=8
VMS$IRPCOUNT=30
VMS$IRPCOUNTV=800
VMS$LGI_BRK_TMO=0
***** OLD_PARAMS.DAT
VMS$ACP_SYSACC=4
VMS$IRPCOUNT=30
VMS$IRPCOUNTV=2000
VMS$LGI_BRK_TMO=0
*****
***** working_params.dat
VMS$LGI_HID_TIM=0
VMS$LOCKIDTBL=40
VMS$LRPCOUNT=8
***** OLD_PARAMS.DAT
VMS$LGI_HID_TIM=0
VMS$LRPCOUNT=8
*****
***** working_params.dat
VMS$MPW_LOLIMIT=120
VMS$NPAGEDYN=120000
VMS$NPAGEVIR=256000
VMS$RESHASHTBL=20
VMS$RJOBLIM=10
VMS$SCSBUFFCNT=3
VMS$SCSRESPCNT=20
VMS$SRPCOUNT=60
VMS$SRPCOUNTV=1200
VMS$SWPOUTPGCNT=80
***** OLD_PARAMS.DAT
VMS$MPW_LOLIMIT=120
VMS$SRPCOUNT=60
VMS$SRPCOUNTV=3000
VMS$SWPOUTPGCNT=80
*****
***** working_params.dat
VMS$VMSIMAGES_GBLSECTIONS=17
! Parameters specified in SYS$SYSTEM:MODPARAMS.DAT
ADD_VIRTUALPAGECNT = 10000 ! Give the compiler more "virtual" room
MIN_PGFLQUOTA = 10000 ! Ensure your user account can use it
MIN_GBLPAGES = 3000
MIN_GBLSECTIONS = 100
MIN_VIRTUALPAGECNT = 12000
!
***** OLD_PARAMS.DAT
VMS$VMSIMAGES_GBLSECTIONS=17
!
! This data file should NOT be modified. Users wishing to alter the
! data in this file should modify SYS$SYSTEM:MODPARAMS.DAT instead.
!
*****
***** working_params.dat
! This data file should NOT be modified. Users wishing to alter the
! data in this file should modify SYS$SYSTEM:MODPARAMS.DAT instead.
!
***** OLD_PARAMS.DAT
*****Memory size and CPU Type were obvious ones, but others were beyond me. MIN_GBLSECTIONS=100 was the last change that i made to get the Pascal compiler working.
But then, maybe it was not actually fixed. At random the error would return, and then, just as randomly, fix itself. A different conversation with Gemini suggested that the emulation was potentially part of the issue.
Throttle SIMH (The "Race Condition" Fix):If your host PC is very fast, SIMH can process instructions faster than the emulated VMS 4.7 clock/interrupt handlers expect, causing internal timing errors in the compiler's memory management.In your SIMH configuration file (or at the sim> prompt), try:
textsim> SET THROTTLE 1M
Use code with caution.(This slows the virtual VAX down to ~1 MIPS, closer to a real MicroVAX I speed, which often stabilizes older compilers).Remarkably, this does seem to have settled the issue down. I have set the throttle to 300k as per the option in the microvax1.ini file. I cannot be sure whether the various other “optimisations” mattered at all!
I ended up sticking with earlier versions of C and Pascal just to minimise consumption of disk space.
I turned off networking via the SYS$SYSTEM:SYSTARTUP.COM file. The networking component could be removed. Practically, the system is already struggling so it is unlikely that i will add a network card unless i find more disk space and memory at a sensible cost.
I have less than 5MB of disk space left, but that should be enough to play with the compilers.
For the record, my microvax1.ini file is:
; ================================================
; microvax1.ini
; ================================================
;
; KD32 CPU
; 2 MSV11-QA = 2MB Memory (or 4 MSV11-PL)
; DZV11 Four-Channel Asynchronous Serial Interface
; RQDX1 Floppy/Fixed Disk Controller
; RX50 400KB 5.25" Dual Floppy Drive
; RD52 31MB 5.25" Fixed Disk
; DEQNA Ethernet Network Adapter
SET QUIET
SET CONSOLE LOG=uVMS_gen_installed_001.log
SET CPU IDLE=VMS
; Uncomment the next line if you want a more realistic MicroVAX I speed
SET THROTTLE 300K
; This seems to help reduce pascal compiler errors.
SET CPU 2M
; The RD52 at 30MB is the largest drive supported by the RQDX1 Floppy/Fixed Disk Controller
SET RQ0 RD52
; Becomes DUA0:
ATT RQ0 MicroVMS_47.rd52
; This originally came from the MicroVAX II emulation.
SET RQ1 RX50
; Becomes DUA1:
SET RQ2 RX50
; Becomes DUA2:
SET RQ3 ENABLE
SET RQ3 RD52
; Becomes DUA3:
; This image is a copy of a drive on the 8650 emulation.
; It has the software kits.
ATT RQ3 share2_795.vhd
SET DZ ENABLE
; The real machine does not have this card.
SET DZ LINES=4
ATT DZ 6666
SET LPT DIS
SET RL DIS
SET XQ ENA
; The real machine does not have this card.
SET XQ TYPE=DEQNA
BOOT RQ0
I created (ok AI created) a program to calculate prime numbers in Pascal, C, Fortran, and Basic. They all compile, link, and run just fine which is rather pleasing. Curiously, Basic is a compiler, but has an editing mode that looks and behaves much like an interpreter. The macro assembler that ships with MicroVMS is also present, so there are a total of 5 languages to choose from.
I think this is now ready for the long journey to the physical Microvax I.