Low-Level Formatting DEC MFM Disks - Revision history

Jnc: Avoid redir

2025-11-13T23:39:21Z

Avoid redir

Vaxorcist: Changed the introductory sentence wording.

2025-11-09T19:06:07Z

Changed the introductory sentence wording.

Vaxorcist: Some categories added

2025-11-07T08:04:02Z

Some categories added

Vaxorcist: /* Formatting a Known Hard Disk */ Link added.

2025-11-07T07:43:35Z

‎Formatting a Known Hard Disk: Link added.

Vaxorcist: /* Preparations */ Some links added.

2025-11-07T07:38:50Z

‎Preparations: Some links added.

Vaxorcist: New Page "Low-Level Formatting DEC MFM Disks"

2025-11-06T21:14:13Z

New Page "Low-Level Formatting DEC MFM Disks"

New page

There are several occasions where you possibly want (or even need) to low-level format a [[DEC]] [[MFM]] disk:

* Testing for bad blocks
* Reformatting from a PC-like low-level format
* Reformatting for use on another type of [[RQDX Series of MFM Disk & Floppy QBUS Controllers|RQDX]] MFM controller
* Reformatting for spoofing another disk model
* ...

Another scenario might be that you want to prepare a foreign MFM disk model as a replacement for a DEC MFM disk.

You can even reformat [[RLL]]-type disks for usage on MFM controllers for the price of loosing some disk space.

== Preparations ==

All you need is:

* A MicroVAX 2000 / VAXstation 2000

or:

* An [[RQDX1]], [[RQDX2]], or [[RQDX3]] [[QBUS]] MFM controller suitable for your MFM disk, and
* An [[RX50]] Dual Floppy Drive, and
* A MicroPDP, or
* A MicroVAX I / VAXstation I, or
* A MicroVAX II / VAXstation II, or
* A later QBUS based MicroVAX / VAXstation

== Using a VAXstation 2000 or MicroVAX 2000 and its ROM resident Diagnostics ==

=== Formatting a Known Hard Disk ===

Example of formatting an RD32 hard disk:
>>> '''TEST 70'''

VSfmt_QUE_unitno (0-2) ? '''0''' [enter the drive number of the hard disk]

VSfmt_STS_Siz........... RD32 [formatter recognized DUA0 as a RD32]

VSfmt_QUE_SerNbr (0-999999999) '''29042836''' [enter the serial number for the drive]
[or enter a unique number for each unit]

VSfmt_QUE_RUsure (DUAx 1/0) ? '''1''' [where x equals the unit number]
[enter 1 for YES, 0 for NO]

VSfmt_STS_RdMbb.............OK [manufacturer's bad block located]

VSfmt_STS_FMTing............OK [disk formatted OK]

VSfmt_STS_ChkPss............OK [check pass completed OK]

VSfmt_STS_BBRvec := x [x = number of bad blocks revectored]

VSfmt_RES_Succ [disk is successfully formatted]

>>>

=== Formatting an Unknown Hard Disk ===

>>> '''TEST 70'''

VSfmt_QUE_unitno (0-2) ? '''0''' [Enter drive number]

VSfmt_STS_Siz .......... ???? [Formatter does not recognize drive type]

VSfmt_STS_EntUIB [Formatter wants drive details]

[this example is from the VS2000 technical manual]

xbnsiz :=54 [enter the number of transfer blocks]

dbnsiz :=48 [enter the number of diagnostic blocks]

lbnsiz :=83236 [enter the number of logical blocks]

rbnsiz :=200 [enter the number of replacement blocks]

surpun :=6 [enter the number of surfaces per unit]

cylpun :=820 [enter the number of cylinders per unit]

wrtprc :=820 [enter the write precompensation cylinder]

rctsiz :=4 [enter the size of the revectoring control table (RCT)]

rctnbr :=8 [enter the number of copies of the RCT]

secitl :=1 [enter the sector interleave]

stsskw :=2 [enter the surface to surface skew]

ctcskw :=9 [enter the cylinder to cylinder skew]

mediai :=627327008 [enter the MSCP media ID]

* Note this number is not dependent on disk geometry, but is the magic number for VMS to report on the type of disk. *
At this point, the formatter exits the query mode.

The next output to the screen is:
VSfmt_QUE_SerNbr (0-999999999) [enter the serial number for the drive]
[or enter a unique number for each unit]

VSfmt_QUE_RUsure (DUAx 1/0) ? [where x equals the unit number]
[enter 1 for YES, 0 for NO]

The formatter is now running, and the output should look like:

VSfmt_STS_RdMbb.............OK [manufacturer's bad block located]

VSfmt_STS_FMTing............OK [disk formatted OK]

VSfmt_STS_ChkPss............OK [check pass completed OK]

VSfmt_STS_BBRvec := x [x = number of bad blocks revectored]

VSfmt_RES_Succ [disk is successfully formatted]

>>>

== Using a MicroVAX I and the VAX Diagnostic Supervisor ==

Get the [http://xxx.com MicroVAX I diagnostic floppies set images]:

[[Writing Floppy-Fixed Disk and Tape Images to Real Media using VMS | Write <code>BL-T857D-DE MICROVAX I Diagnostics 2(3).RX5</code> onto an RX50 floppy or workalike.]]

Put floppy BL-T857D-DE into RX50 drive 0.

Boot VAX Diagnostic Supervisor (VDS):
B/10 DUA0

Load EHXRQ diagnostic
ATT RQDX1 HUB DUA 772150
ATT RX50 DUA DUA0
SET LOAD DUA0:[SYS0.SYSMAINT]
LOAD EHXRQ

Prepare & start formatting e.g. an RD52:
ATTACH RD52 DUA DUA1
SELECT DUA1
START /SECTION=FORMATTER

== Using a MicroVAX II or later MicroVAX and the MicroVAX Diagnostic Monitor ==

== Using a MicroPDP and the XXDP Diagnostics ==

ZRQBxx RQDX1/2

ZRQCxx RQDX3

PDP11_DiagnosticHandbook_XXDP_1988 mit Text.pdf

DR> STA

CHANGE HW (L) ? Y

# UNITS (D) ? 1

UNIT 0
Enter controller IP address (O) 172150 ?
What unit do you want to format [0-255] (D) 0 ? 1
Would you like to revector a single LBN only [Y/N] (L) N ?
Do you want to use the "AUTOFORMAT" Mode [Y/N] (L) Y ? N

Would you like to use the RCT - Revector known bad blocks [Y/N] (L) N ?

**** WARNING ****

[text about don't proceed if you're just kidding deleted]

Do you wish to continue [Y/N] (L) Y ?

MSCP Controller Model: 19
Microcode Version: 4

Do you want to use manufacturing bad block information [Y/N] (A) N ?

Downline load UIT [Y/N] (A) Y ?

UIT Drive Name
-------------------------------------------------------
0 RD51
1 RD52 part # 30-21721-02 (1 light on front panel)
2 RD52 part # 30-23227-02 (2 lights on front panel)
3 RD53
4 RD31
5 RD54
6 RD32

Enter Unit Identifier Table (UIT) [0-7] (D) ? 5

Continue if bad block information is inaccessible [Y/N] (A) N ? Y

Please type in the serial number [8-10 digits] (A) ? 05388342

Formatting of Drive 1 Begin.

[a long sequences of messages is displayed here, 1 per minute, showing the
progress of formatting and what step is in progress on which block number.]

Format Completed.

00001 Rev LBNs
00000 Bad RBNs
00000 Bad DBNs
00000 Bad XBNs
00001 retired

FCT was not used.

Drive 1 has been formatted successfully.

ZRQC EOP 1
0 TOTAL ERRS

DR>

@@ Line 1: / Line 1: @@
-There are several situations in which you may want (or even need) to format a [[DEC]] [[MFM]] disk:
+There are several situations in which you may want (or even need) to format a [[Modified Frequency Modulation|MFM]] disk from [[Digital Equipment Corporation|DEC]]:
 * Testing for bad blocks
@@ Line 9: / Line 9: @@
 Another scenario might be that you want to prepare a foreign MFM disk model as a replacement for a DEC MFM disk.
-You can even reformat [[RLL]]-type disks for usage on MFM controllers for the price of loosing some disk space.
+You can even reformat [[Run-length limited coding|RLL]]-type disks for usage on MFM controllers at the price of losing some disk space.
 == Preparations ==

← Older revision		Revision as of 19:06, 9 November 2025
Line 1:		Line 1:
−	There are several ~~occasions where~~ you ~~possibly~~ want (or even need) to ~~low-level~~ format a [[DEC]] [[MFM]] disk:	+	There are several situations in which you may want (or even need) to format a [[DEC]] [[MFM]] disk:

	* Testing for bad blocks		* Testing for bad blocks

← Older revision		Revision as of 08:04, 7 November 2025
Line 220:		Line 220:

	DR>		DR>
		+
		+	[[Category: DEC Disk Drives]]
		+	[[Category: MSCP Disk Drives]]
		+	[[Category: DEC Non-removable-media Disks]]
		+	[[Category: ST506 Disk Drives]]

@@ Line 30: / Line 30: @@
 === Formatting a Known Hard Disk ===
-Example of formatting an RD32 hard disk:
+Example of formatting an [[RD32]] hard disk.
   >>> '''TEST 70'''
   VSfmt_QUE_unitno (0-2) ? '''0'''      [enter the drive number of the hard disk]
-  VSfmt_STS_Siz........... RD32   [formatter recognized DUA0 as a RD32]
+  VSfmt_STS_Siz........... '''RD32'''   [formatter recognized DUA0 as a RD32]
   VSfmt_QUE_SerNbr (0-999999999)  '''29042836'''   [enter the serial number for the drive]

@@ Line 15: / Line 15: @@
 All you need is:
-* A MicroVAX 2000 / VAXstation 2000
+* A [[MicroVAX 2000]] / [[VAXstation 2000]]
 or:
-* An [[RQDX1]], [[RQDX2]], or [[RQDX3]] [[QBUS]] MFM controller suitable for your MFM disk, and
+* An [[RQDX1/RQDX2 MFM Disk & Floppy QBUS Controllers|RQDX1, RQDX2]], or [[RQDX3 MFM Disk & Floppy QBUS Controller|RQDX3]] [[QBUS]] MFM controller suitable for your MFM disk, and
 * An [[RX50]] Dual Floppy Drive, and
-* A MicroPDP, or
+* A [[MicroPDP-11]], or
-* A MicroVAX I / VAXstation I, or
+* A [[MicroVAX I]] / [[VAXstation I]], or
-* A MicroVAX II / VAXstation II, or
+* A [[MicroVAX II]] / [[VAXstation II]], or
-* A later QBUS based MicroVAX / VAXstation
+* A later [[QBUS]] based [[MicroVAX]] / [[VAXstation]]
 == Using a VAXstation 2000 or MicroVAX 2000 and its ROM resident Diagnostics ==