Format RD54 in MicroVAX II (630QY)

[wa2flq]

I have a RD54 (aka XT2190) that is currently only a boat anchor. So I'm reaching out to get some advice on how to attack the problem of creating a bootable diagnostic tape, so I can take a shot at reformatting it. The drive has bit rot typical for its heritage. I'm hoping a reformat will leave it in a more usable state.

I've tried to find or build a tape with the MDM diagnostic. This link seems to have all the necessary files - AQ-QL5AH-DN (http://www.vaxination.ca/vms/microvax/mv_ii.html). However after building a TK52-K (CompacTape II) it refuses to boot.

>>> b mua0
2..
?43 FILESTRUCT, MUA0
?06 HLT INST
PC = 00000EE6​

Others have seen the same challenge. I have built a VMS 5.5 STABACKIT on the same tape cartridge (from a MV3100). The MVII loads Standalone Backup just fine and sees the RD54, so the basic hardware and tape media is ok.

I also looked a MDM kit that appears to be used for SIMH AQ-GL5AE-DN.tk50 (http://www.9track.net/vax/mv2diag.zip). The file is in a virtual tape format and along with some metadata, has captured the headers. I don't currently have a way to create a tape from this source. But looking at dump of the content, it appears the MDM files are built on the tape differently that what I see when I create my own tape under VMS via copy.

I suspect that the original diagnostic tapes used 512 byte records for the files (sysboot.exe, etc..) while the tape I create under with VMS copy uses a different record size (2048 bytes). The STABACKIT uses 512 byte records. There is a setsize program created on the fly for this purpose. Does anyone know if this record size is a limitation in the MVII onboard VMB? Or does this diagnostic just not work on a TK52-K? I don't have a way to write a TK50-K at the moment.

Thanks is advance for any advice or feedback.

 

[wa2flq]

MVII Diagnostic Progress (some..)

MVII Diagnostic Progress (some..)

About three hours after posting this I was able to create a functional TK50 Tape. After initializing a tape, it has to be mounted with a blocksize of 512. If you don’t do this, then the default is 2048 and the tapes are will not boot. I also used $copy/truncate/contiguous to create files on the tape.

VAXELN V2.2-00

MicroVAX Maintenance System - Version 2.0
The current date and time is: 23-JUN-1982 07:10:28.67


MAIN MENU
SYSTEM CONFIGURATION AND DEVICES

CPUA ... MicroVAX CPU
KA630-AA 1MB, FPU MC=00 HW=00
MEMA ... MicroVAX memory system
16 megabytes. 32768 Pages.
KA630 ... CPU module, disabled on-board memory.
MS630-CA ... Quad height memory module, 8MB.
MS630-CA ... Quad height memory module, 8MB.
RQDXA ... Winchester/diskette controller.
Revisions =4 and 1
DEQNAA ... Ethernet controller.​

Unforunately attempts to (re)format the drive haven't been successful. The customer version dies shortly after starting. I verified the controller, necessary eprom version and disk settings are correct. Not much in the way of information is provided. It just says formatting failed

I might temporarily put in a 11/23 and find a XXDP+ version of the formatter. It has more knobs and switches and perhaps more feedback on the process. Maybe the Support version "MVII DIAG MAINT TK50” has more options as well, but I haven't found a source.

 

[vaxorcist]

I remember I tried MDM to reformat RD-disks a long time ago - I had several genuine MDM tapes. It all failed: The tapes that were still readable were MDM customer versions without the formatter and the only "field service" one left its magnetic parts mostly at the TK50 rollers ...

Today I have two different methods at hands:

1) My PDP-11/83 running XXDP (re-)formats all kinds of RD disk and compatible ones
2) My VAXstation 2000 can do nearly the same from its system ROM

I do not rely on TK50 drives anymore, partly because of failing drives and partly because of self-destructing TK50 cassettes, which in turn often damage drives, too.

I install my MicroVAXen with the help of images made with simh, which are transferred to the target computer disk via LAVC clustering (diskless booting the satellite MicroVAX into an LAVC).

I don't know whether you can do any of the methods described above, but maybe you get inspired!

Regards,

Ulli