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Document:	Device Extensions User’s Guide
Order Number:	AA-D319A-TA
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Pages:	49
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OS/8
Device Extensions
User's Guide
Order No. AA-D3 19A-TA

OW8
Device Extensions
User's Guide
Order No. AA-D319A-TA

ABSTRACT
This document describes the software support for the KT8A
Memory Management Option and the RX02 and RL01 devices.

SUPERSESSIONIUPDATE INFORMATION: This manual is an update of sections of the
OSl8 Handbook (DEC-S8-OSHBA-A-D).
OPERATING SYSTEM AND VERSION:

OSl8 V3D

To order additional copies of this document, contact the Software Distribution
Center, Digital Equipment Corporation, Maynard, Massachusetts 01754

digital equipment corporation magnard, massachusebbs

First Printing, December 1978

The information in this document is subject to change without notice
and should not be construed as a commitment by Digital Equ-nt
Corporation. Digital Equipment Corporation assumes no responsibility
for any errors that may appear in this document.
The software described in this document is furnished under a license
and may only be used or copied in accordance with the terms of such
license.
No responsibility is assumed for the use or reliability of software on
equipment that is not supplied by DIGITAL or its affiliated companies.

@ 1978 by Digital Equipment Corporation

The postage-prepaid READER'S COMMENTS form on the last page of this
document requests the user's critical evaluation to assist us in preparing future documentation.
The following are trademarks of Digital Equipment Corporation:

DIGITAL
DEC
PDP
DECUS
UNIBUS
COMPUTER LABS
COMTEX
DDT
DECCOMM
ASSIST-11
VAX
DECnet

DECsystem-10
DECtape
DIBOL
EDUSYSTEM
FLIP CHIP
FOCAL
INDAC
LAB-8
DECSYSTEM-20
RTS-8
VMS
IAS

MASSBUS
OMNIBUS
OS/8
PHA
RSTS
RSX
TYPESET-8
TYPESET-11
TMS-11
ITPS-10
SBI

CONTENTS

Page
INTRODUCTION AND OVERVIEW
D i s t r i b u t i o n Media
T h e RESORC P r o g r a m
C h a n g e s i n BASIC and FORTRAN I V f o r R L 0 1 and
RX02 U s e r s
System-Wide C h a n g e s f o r U s e r s w i t h t h e KT8A
C h a n g e s i n P I P f o r R L 0 1 , RX02, and VXAO
T h e BOOT.SV P r o g r a m
C h a n g e s i n FUTIL
BOOTSTRAP AND BUILD INSTRUCTIONS
THE KT8A MEMORY MANAGEMENT OPTION
SAVE, ODT, and
1 2 8 K M o n i t o r and CCL C o m m a n d s
MEMORY
T h e SAVE Command
T h e ODT Command
T h e CCL M e m o r y Command
1 2 8 K PAL8
T h e FIELD P s e u d o - O p e r a t o r
S p e c i f y i n g D a t a and I n s t r u c t i o n F i e l d s
CDF
and C I F
T h e ABSLDR
D e t e r m i n i n g M e m o r y - S i z e a t Run-Time
T h e VXAO E x t e n d e d - M e m o r y D e v i c e
T h e SAVECB P r o g r a m
THE RX0 2 DUAL-DENSITY DISKETTE
RX02 D e v i c e N a m e s
F o r m a t t i n g D i s k e t t e s f o r RX02
RX01 and RX02 C o m p a t i b i l i t y

Interleaving
U s i n g RXCOPY w i t h RX02
F o r m a t t i n g D i s k e t t e s w i t h RXCOPY
RXCOPY O p t i o n s
THE R L 0 1 DISK
System Description
D i s k Format
RL8A C o n t r o l l e r F o r m a t
Instruction S e t
OS/8 D a t a S p a c e
C o n v e r t i n g B l o c k Numbers t o Hardware D i s k
Addresses
Handler Description
L o a d i n g and B o o t s t r a p P r o c e d u r e
L o a d i n g t h e RL01 D i s k P a c k
B o o t i n g f r o m BOOTeSV
B o o t i n g from the C o n s o l e S w i t c h e s
ROM B o o t s t r a p S w i t c h S e t t i n g s
O p e r a t i n g Instructions
Disk Formatting
System Building

iii

CONTENTS (Cant.)

Page
APPENDIX A

RX02 BOOTSTRAP PROGRAM

A-1

APPENDIX B

RL01 BOOTSTRAP PROGRAM

B-1
I ndex- 1

INDEX

FI GURE S
FIGURE

1
2

Memory-Size Subroutine
Devices A, B I C on RL01 Disk

TABLES
TABLE

1
2
3
4
5
6
7
8
9
10

Device Extensions Modules
RX02 Bootstrap
RL01 Bootstrap
128K ODT Command Summary
Field Specifications for 128K MEMORY Command
RX01-RX02 Compatibility
OS/8 Single Density Diskette Interleave Scheme
OS/8 Double Density Diskette Interleave Scheme
RL01 Handler Information
RLFRMT Formatter Messages

1.0

INTRODUCTION AND OVERVIEW

The OS/8 V3D Device Extensions support the following new devices under
OS/8.
0
0

The KT8A Memory Management Option (limited support)
The RL01 Disk and Controller
The RX02 Double-Density Diskette and Controller

In addition, the Extensions package is a support release for RTS/8 V3
and MACREL/LINK Version 2, both of which can use the extended memory
provided by the KT8A. RTS/8 V3 also supports the RL01 and RX02.
The Extensions package is a superset of some OS/8 modules. It remains
completely compatible with OS/8 V3D and contains the modules listed in
Table 1.
Table 1
Device Extensions Modules
System Programs:
Name

New Version Number

Comment

OS8 MONITOR

system head,
capable
of
being run from the device,
supports
128K
words
of
memory

ABSLDR. SV

loads binary and image
into fields >7

PAL8.SV

uses fields >7

CCL sv

code

CCL
MEMORY
command
recognizes up to 128K words
available in system

PIP sv

works with RL01, RX02, VXAO,
and new system head

RESORC SV

includes RL01,
VXAO

BOOT. SV

includes primary bootstrap
for RL01, RX02, and VXAO

RX02,

and

RXCOPY SV

formats single or
double
density
diskettes, copies
single density to
single
density and double density
to double density

FUTIL .SV

recognizes new core control
block format for programs in
extended memory
(continued on next page)

Table 1 (Cont.)
Device Upgrade Kit Modules
Patches:

(to be added with LOAD and SAVE commands)
--

Comment.

New Version Number

Name

.
FPAT .BN

Patch for BASIC

BPAT BN

Handlers:

Patch for FORTRAN IV
(to be inserted with BUILD)

RL01 System Handler

RLSY BN

RL01 Non-system Handlers

RLO BN
RL1. BN
RL2. BN
RL3. BN

RLC BN
VXSY BN

VXAO System Handler

RXSY 1 .BN

RX01 System Handler

RXSY2. BN

RX02 System Handler

RXNS BN

---

RX01-RX02 Non-system Handler

This manual assumes that the user is familiar with the material in the
following documents:
OS/8 Handbook (DEC-S8-OSHBA-A-D)
OS/8 Handbook Update (DEC-S8-OSHBA-A-DN4)
OS/8 Software Support Manual (DEC-S8-OSSMB-A-D)
KTÃˆ Memory Manaqement Control User's Guide (EK-KT0
RL8A Disk Controller Maintenance Manual (EK-RL8A-TM

1.1

Distribution Media

The OS/8 Device Extensions are distributed on the following media.
RX02 diskette
RL01 disk
RK05 disk

TD8E DECtape

1.2

The RESORC Program

The new RESORC program lists the system and non-system handlers for
the
RX02 and RL01 devices.
In addition, it lists a special
handler -- called VXAO -- that enables you to use the extended memory
provided by the KT8A as though it were a separate device.
RESORC now has an overlay structure, enabling a user who buys
source program to enter information on user-written handlers.

the

1.3

Changes in BASIC and FORTRAN IV for R L 0 1 and R X 0 2 Users

RL01 and RX02 users must add the following patches to the BASIC and
FORTRAN IV run-time systems so that these programs recognize and
properly allocate space in memory for the second page of the system
handlers.
To patch the BASIC run-time system, enter the following commands.

where
dev

is the distribution device

BPAT.BN

is the BASIC patch

To patch the FORTRAN IV run-time system, enter the following commands.

where

1.4

dev

is the distribution device

FPAT.BN

is the FORTRAN IV patch

System-Wide Changes for Users with the KT8A

KT8A users must ensure that user-written programs and user-written
handlers do not contain the following combination of instruction
steps.
CIF
IOT
JMP I

/Change instruction field
/Any PDP8 IOT instruction
/The instruction that does the CIF

If you enable the KT8A and turn on the interrupts (for example, to run
OS/8 as a background task under RTS8), the KT8A hardware will return
to the wrong place on traps between the CIF and JMP I instructions.

1.5

Changes in PIP for R L 0 1 , R X 0 2 , and VXAO

The new-version of PIP recognizes the RL01, RX02, and VXAO devices.
PIP sets the proper length for directories on the ZERO command and
a
double-density
or
determines whether it is
dealing
with
single-density diskette.
PIP also recognizes the new Monitor head. If you attempt to use the Y
option on the old version of PIP to move the new system head, PIP
responds with the error message
B A D SYSTEM HEAD

1.6

The BOOT.SV Program

The BOOT.SV program now i n c l u d e s a primary b o o t s t r a p f o r
and VXAO.
The format i s

RL01,

RX02,

BOOT
/dd

where

i s a l e g a l OS/8 d e v i c e s p e c i f i c a t i o n , incl.uding R L , R X ,
o r VX.

1.7

Changes i n FUTIL

The new v e r s i o n of t h e OS/8 f i l e u t i l i t y program FUTIL r e c o g n i z e s t h e
new Core C o n t r o l Block format f o r user-programs i n extended memory.
For a complete d e s c r i p t i o n of FUTIL, s e e t h e OS/8 Handbook Update.

2.0

BOOTSTRAP AND BUILD INSTRUCTIONS

Since the Extensions
bootstrap the RX01,
system d e v i c e .

package
i n c l u d e s t h e system head,
you can
RX02, RL01, o r RK05 d i s t r i b u t i o n medium a s a

T a b l e 2 and T a b l e
and
RL01
device.
the
TD8E
DECtape
Handbook.

3
contain
the
bootstraps for
the
RX02
The
bootstraps
for
the
PiKO5
disk
and
are
included
in
Chapter 1 of
t h e OS/8

The new h a n d l e r s m u s t be i n s e r t e d i n t o OS/8 w i t h t h e B U I L D program.
For
i n f o r m a t i o n on adding h a n d l e r s t o OS/8, s e e t h e B U I L D c h a p t e r i n
t h e OS/8 Handbook.
NOTE
The c o n s o l e i n s t r u c t i o n s i n T a b l e s 2 and
3 d e s c r i b e a PDP8-A.
For o t h e r PDP8
computers, s e e t h e OS/8 Handbook.
Table 2
RX02 Bootstrap

P r e s s i n o r d e r t h e MD and DISP b u t t o n s t o d i s p l a y memory
i n t h e o c t a l readout.

P r e s s i n o r d e r 0 and LXA t o s e l e c t memory f i e l d 0.

P r e s s i n o r d e r 20 and LA
location 20.

start

instructions

data

( c o n t i n u e d on n e x t page)

Table 2
(Cont.)
RXU2 B o o t s t r a p
4.

Deposit t h e following o c t a l
w i t h D NEXT.

values,

terminating

each

value

A f t e r you have d e p o s i t e d a l l t h e v a l u e s , p r e s s 0033 and LA
s t a r t t h e program a t l o c a t i o n 33.

To s t a r t t h e b o o t s t r a p program, p r e s s I N I T and RUN.

Table 3
RL01 B o o t s t r a p
1.

P r e s s i n o r d e r t h e MD and DISP b u t t o n s t o d i s p l a y memory
i n t h e o c t a l readout.

P r e s s , i n o r d e r , 0 and LXA t o s e l e c t memory f i e l d 0.

P r e s s , i n o r d e r , 1 and LA t o
a d d r e s s 1.

start

instructions

data

( c o n t i n u e d on n e x t page)

Table 3 (Cont.)
RL01 B o o t s t r a p
4.

Deposit t h e o c t a l values given
w i t h D NEXT.
Address

below,

following

each

value

Contents

A f t e r a l l v a l u e s a r e d e p o s i t e d , p r e s s , i n o r d e r , 0 0 0 1 and LA
t o a l l o w t h e program t o s t a r t a t l o c a t i o n 1.

P r e s s , i n o r d e r , I N I T and RUN t o s t a r t t h e b o o t s t r a p program.

The c o m p l e t e RX02 and RL01 b o o t s t r a p p r o g r a m s a r e l i s t e d i n Appendix A
and B.

3.0

THE KT8A MEMORY MANAGEMENT OPTION

The OS/8 V3D D e v i c e E x t e n s i o n s p r o v i d e l i m i t e d s u p p o r t f o r t h e KT8A
Memory E x t e n s i o n and Management O p t i o n , which i n c r e a s e s t h e amount o f
a l l o w a b l e memory i n PDP8 s y s t e m s from 32K t o a maximum o f 128K words.
The KT8A s u p p o r t s a l l a v a i l a b l e s i z e s o f c o n t i n u o u s memory from 32K t o
128K.
System p r o g r a m s , d e v i c e s , and l a n g u a g e s t h a t r u n i n 32K under OS/8
w i l l a l s o o p e r a t e w i t h t h e new m o n i t o r .
I n addition, systems with t h e
KT8A and 128K s o f t w a r e s u p p o r t w i l l r u n u s e r - w r i t t e n
programs i n
memory f i e l d s 0 t o 37. OS/8 h i g h - l e v e l l a n g u a g e s and s y s t e m p r o g r a m s ,
however, d o n o t make u s e o f memory g r e a t e r t h a n 32K words.

This section describes the OS/8 commands and PAL8 instructions that
allow you to run user-written programs in fields 0 through 37. In
addition, it includes a subroutine for finding the amount of memory
available at run-time and describes a program that enables you to
chdnge the Core Control Block of a program in complex SAVE operations.
This section also notes current software restrictions on
the extended memory.

the

use

For a description of the KT8A device, including operating and
programming instructions, see the KT8A Memory ~anaqementcontrol
User ' s Guide (EK-KTO8A-UG-001)

3.1

128K Monitor and CCL Commands

-- SAVE, ODT, and MEMORY

The SAVE and ODT monitor commands now support fields 0 to 37. The CCL
MEMORY command finds the highest field available in hardware up to
field 37. MEMORY also limits the available fields in software, but
this feature is currently restricted to 32K.

NOTE
The OS/8 Monitor currently requires that
all user-written programs contain at
least one segment (1-page minimum) below
32K.

3.1.1 The SAVE Command - The SAVE command makes a memory-image file
of the program currently in memory, assigns it a name, and saves it on
a device. You can specify areas in memory that you want to save in
fields from 0 to 37.
The format of the command, including all optional arguments, is
SAVE device:file.ex

ffnnnn-ffmmmm,ffpppp;ffssss=cccc

where
ffnnnn

is a 6-digit octal number representing a field from 0
to 37 (ff) and the first address of a continuous
portion of memory you want to save.

ffmmmm

is the final address (in the same field) of the section
of memory you want to save.

~ ~ P P P P is a 6-digit octal number representing the

field and
address of one location in memory. If you specify a
single address on an even-numbered page in the command,
SAVE writes the entire page on which the location
occurs. If you specify an odd-numbered page, SAVE also
saves the preceding page*

;ffssss

is a 6-digit octal number representing the field
starting address of the program you are saving*

and

=cccc

is a 4-digit octal number representing the contents of
the Job Status Word for the program. (See below.)

I f you omit t h e e x t e n s i o n on t h e f i l e name, SAVE appends .SV.
I f you
omit t h e o t h e r arguments, SAVE f i n d s t h e l o c a t i o n s i t r e q u i r e s i n t h e
c u r r e n t Core C o n t r o l Block.
(For a d i s c u s s i o n of t h e Core C o n t r o l
Block, s e e t h e OS/8 Handbook and t h e OS/8 Software Support Manual.)
The SAVE command p l a c e s t h e f o l l o w i n g r e s t r i c t i o n on arguments i n
command 1 i n e

You m u s t s p e c i f y t h e o u t p u t d e v i c e *
DSK

SAVE does n o t d e f a u l t

the
to

The f i r s t and l a s t l o c a t i o n of a
segment
in
memory
(ffnnnn-ffmmmm)
t h a t you wish t o SAVE must both e x i s t i n t h e
same f i e l d . You may n o t c r o s s f i e l d boundaries.
In the
following example, both e n t r i e s s p e c i f y f i e l d 22.

Wheh you s p e c i f y an a r e a on a page, SAVE t a k e s t h e e n t i r e
page.
I f you c a l l f o r a n o t h e r p a r t of t h a t page i n t h e same
command l i n e , SAVE s e n d s a BAD ARGS e r r o r message t o t h e
t e r m i n a l informing you t h a t i t h a s a l r e a d y saved t h e page.

The f i r s t argument w r i t e s l o c a t i o n s 77 t o 1 2 2 i n f i e l d 12 on
t o R X A l and c a l l s t h e f i l e FL0P.SV.
The second argument,
which s p e c i f i e s l o c a t i o n s on t h e same page, produces t h e e r r o r
message

Do n o t SAVE l o c a t i o n s 7600-7777 i n f i e l d s 0 , 1, and 2.
The
r e s i d e n t Monitor code r e s i d e s i n t h e s e a r e a s of memory. To
avoid a c c i d e n t l y d e s t r o y i n g a p o r t i o n of t h e Monitor, r e s t r i c t
SAVE o p e r a t i o n s i n v o l v i n g 7600 t o f i e l d s above 2.
a

I f you s p e c i f y an a d d r e s s on an odd-numbered page, SAVE can
s a v e i t o n l y i f i t a l s o s a v e s t h e preceding page. The system
does t h i s a u t o m a t i c a l l y .

I f you w i s h t o s p e c i f y more l o c a t i o n s i n a SAVE command than

f i t in a single
S e c t i o n 3.5.

command

you can
l i n e , use t h e SAVECB program d e s c r i b e d i n

NOTE

The Monitor START command
currently
accepts
f i e l d specifications in the
range of 0 t o 7 o n l y *
3.1.2
The ODT Command - ODT a c c e p t s and r e t u r n s 6 - d i g i t a d d r e s s e s
t h e f o l l o w i n g commands.

where
Â£

nnnn

i s a f i e l d from 0 t o 37
is a location

The D and F command allow you to specify fields in the range of 0 to
37- To indicate the first eight fields! type a single octal digit
(0-7). Note that this is a change from previous versions of ODTf
which required you to enter field specifications as multiples of 10
(for example, field 2 as 20). Table 4 summarizes all of the OS/8 128K
ODT commandsm For complete information on ODTf see the chapter on the
ODT program in the 0 ~ / 8HandbookTable 4
128K ODT Command summary
Command

Operation
Open location ffnnnn! where ff is a field from 0
to
37.
ODT displays the contents of the
locationf prints a space! and waits for you to
enter a new value for the location or close the
locationm If you omit fff ODT assumes field 0.
Reopen the most recently opened location-

nnnn;

Deposit nnnn in the currently opened locationf
close the location! and open the next location
in the sequence for modificationm The semicolon
(;)
lets you deposit a series of octal values in
sequential locationsm To skip locations in the
sequence! type a semicolon for each location you
wish to leave unchanged-

RETURN key

Close the currently open location-

LINE FEED key

Close the currently open locationf open the next
location in the sequence for modification, and
display its contents.
Open the current location plus n and display the
contents
Open the current location minus
the contents-

uparrow or
circumflex

and

display

Close the location! read its contents as a
memory-reference instruction and
open
the
location it points tof displaying its contentsODT
makes
no
distinction between
instruction op-codes when you use this
command.
It treats all op-codes as
memory-reference instructionsm
Take care when you use this command with
indirectly
referenced
auto- index
registers- If you use the command in
this wayf the contents of the auto-index
register is incremented by one- Check
to see that the register contains the
proper value before proceeding(continued on next page)

Table 4 (Cont.)
128K ODT Command Summary
Command
(underline)

Operation
Close t h e c u r r e n t l o c a t i o n f read t h e c o n t e n t s a s
a t w e l v e - b i t a d d r e s s I and open t h a t l o c a t i o n f o r
modificationf displaying its contents.
E s t a b l i s h a b r e a k p o i n t a t l o c a t i o n f f n n n n , where
f f i n d i c a t e s a f i e l d from 0 t o 37. ODT p e r m i t s
o n l y one b r e a k p o i n t a t a time.
T r a n s f e r c o n t r o l of t h e program
ffnnnnf
where
the
f i r s t two
r e p r e s e n t a memory f i e l d .

t o location
digits (ff)

Remove t h e b r e a k p o i n t I i f one e x i s t s .
Open f o r m o d i f i c a t i o n t h e l o c a t i o n i n which ODT
s t o r e d t h e c o n t e n t s of t h e accumulator when i t
encountered t h e b r e a k p o i n t .
Open f o r m o d i f i c a t i o n t h e l o c a t i o n i n which ODT
stored
the
c o n t e n t s of t h e Link when i t
encountered t h e l a s t b r e a k p o i n t .
Open t h e Search Mask l o c a t i o n f i n i t i a l l y s e t t o
7777.
To change t h e Search Maskf t y p e a new
value i n t o t h e l o c a t i o n .
Open t h e lower s e a r c h - l i m i t l o c a t i o n .
Type i n
t h e l o c a t i o n ( f o u r o c t a l d i g i t s ) where t h e
search w i l l terminate.
Open t h e upper s e a r c h - l i m i t l o c a t i o n .
Type i n
t h e l o c a t i o n ( f o u r o c t a l d i g i t s ) where t h e
search w i l l terminate.
Search t h e p o r t i o n of memory d e f i n e d by t h e
upper and lower l i m i t s f o r t h e o c t a l v a l u e nnnn.
The s e a r c h must be r e s t r i c t e d t o a s i n g l e memory
f i e l d . See t h e F command.
Open f o r m o d i f i c a t i o n t h e l o c a t i o n c o n t a i n i n g
t h e d a t a f i e l d (0 t o 37) t h a t was i n e f f e c t a t
t h e l a s t b r e a k p o i n t . To change t h e f i e l d f e n t e r
a number from 0 t o 37.
Open f o r m o d i f i c a t i o n t h e word c o n t a i n i n g t h e
f i e l d ( 0 t o 37) used by ODT i n t h e l a s t W o r
uparrow command ( s e a r c h o r i n d i r e c t a d d r e s s i n g )
o r i n t h e l a s t b r e a k p o i n t f depending on which
o c c u r r e d most
recently.
To
modify
this
l o c a t i o n f e n t e r a number from 0 t o 37.
CTRL/O

I n t e r r u p t a lengthy search
t h e n e x t QDT command.

output

and w a i t f o r

DELETE key

Cancel a number p r e v i o u s l y t y p e d , up t o t h e
l a s t non-numeric c h a r a c t e r e n t e r e d . ODT responds
w i t h a q u e s t i o n markI a f t e r which you e n t e r t h e
correct location.

3.1.3
The CCL Memory Command
The MEMORY command f i n d s t h e h i g h e s t
f i e l d a v a i l a b l e i n h a r d w a r e up t o f i e l d 37. I t a l s o l i m i t s t h e
a v a i l a b l e f i e l d s i n s o f t w a r e , b u t t h i s f e a t u r e is c u r r e n t l y r e s t r i c t e d
t o 32K w o r d s .
The f o r m a t o f t h e command i s
MEMORY

MEMORY nn

where
i s a n o c t a l number i n t h e r a n g e o f 0 t o 37 r e p r e s e n t i n g
t h e number o f 4 K f i e l d s a v a i l a b l e t o OS/8.

T a b l e 5 l i s t s a l l t h e v a l u e s o f n (memory f i e l d s
c o r r e s p o n d i n g memory-size.

octal)

and

the

Table 5
F i e l d S p e c i f i c a t i o n s f o r 128K MEMORY Command
Words o f Memory
a l l a v a i l a b l e memory
8K
12K
16K
20K
24K
28K
32K
To l i m i t memory, e n t e r t h e h i g h e s t f i l e you w a n t t o make a v a i l a b l e t o
OS/8 i n t h e command l i n e . F o r e x a m p l e , t h e f o l l o w i n g command l i m i t s
t h e a v a i l a b l e memory t o 16K w o r d s .

To f i n d t h e amount o f memory t h a t OS/8 i s u s i n g , t y p e t h e command w i t h
n o argumen t

1% O F 3 2 K MEMORY

I n t h i s e x a m p l e , MEMORY p r i n t s t h e i n f o r m a t i o n t h a t a 32K
b e e n l i m i t e d t o 12K w o r d s .
MEMORY c a u s e d t h e e x e c u t i o n o f t h e CCL.SV

system

has

program.

The f o l l o w i n g PAL8 i n s t r u c t i o n s a c c e p t f i e l d s p e c i f i c a t i o n s i n t h e
r a n g e o f 0 t o 3 7 , p e r m i t t i n g you t o r u n p r o g r a m s i n a r e a s a b o v e 32K.

3.2.1
T h e FIELD P s e u d o - O p e r a t o r - T h e p s e u d o - o p FIELD i n s t r u c t s PAL8
t o o u t p u t a f i e l d s e t t i n g so t h a t i t c a n r e c o g n i z e more t h a n o n e
memory f i e l d .
The f o r m a t o f t h i s pseudo-op

FIELD f f
where
ff

is an integer,
a previously defined
e x p r e s s i o n i n t h e r a n g e 0 t o 37.

symbol,

FIELD c a u s e s t h e PAL8 a s s e m b l e r t o o u t p u t a f i e l d s e t t i n g f r o m 0 t o 3 7
d u r i n g t h e second p a s s o f assembly. T h i s s e t t i n g , which a p p e a r s as
t h e high-order b i t s o f t h e l o c a t i o n c o u n t e r i n t h e program l i s t i n g ,
t e l l s t h e ABSLDR w h i c h f i e l d t o l o a d i n f o r m a t i o n i n t o .
F o r e x a m p l e , t h e f o l l o w i n g FIELD p s e u d o - o p s p e c i f i e s memory f i e l d 2 6 .
The n e x t l i n e sets t h e l o c a t i o n c o u n t e r t o b e g i n a t 400. N o t e t h a t
t h e FIELD i n s t r u c t i o n m u s t p r e c e d e t h e s t a r t i n g l o c a t i o n .
F I E L D 26
*400

/CORRECT

EIXAMPLE

The f o l l o w i n g example is i n c o r r e c t and w i l l n o t g e n e r a t e t h e c o d e
want.
*400

/INCORRECT

you

E.:XAMF'LE:

FIELD 26

3.2.2
S p e c i f y i n g Data a n d I n s t r u c t i o n F i e l d s
CDF a n d C I F - T h e CDF
and CIF i n s t r u c t i o n s l e t you s p e c i f y f i e l d 0 t o 37 a s data and
i n s t r u c t i o n f i e l d s . E n t e r i n g t h e argument r e q u i r e s knowledge o f t h e
b i t a r r a n g e m e n t o f t h e s e two i n s t r u c t i o n s .
A CDE B

CDF

6201

1 1 0 010 000 0 0 1

CIF

6202

1 1 0 010 000 010

B i t s A CDE B i n d i c a t e t h e d a t a o r i n s t r u c t i o n f i e l d t h a t t h e p r o g r a m
(The p o s i t i o n i n g o f
w i l l j u m p t o a t t h e n e x t i n d i r e c t JMP o r JMS.
ABCDE i s e c c e n t r i c a s ACDEB m a i n t a i n s c o m p a t i b i l i t y b e t w e e n KT8A a n d
e x i s t i n g 32K s y s t e m s . )

T o s p e c i f y a f i e l d f r o m 0 t o 7 , y o u u s e b i t s CDE o n l y .
t h e i n s t r u c t i o n is

The f o r m a t

CDF o r C I F no
where
no

i s a n o c t a l number t h a t PAL8 O R s w i t h
code

is a n o c t a l d i g i t f r o m 0 t o 7 ( b i t s CDE)

the

instruction

For example, t h i s i n s t r u c t i o n

s p e c i f i e s f i e l d 6 by c a u s i n g PAL8 t o d o t h e f o l l o w i n g OR.
I n s t r u c t i o n code
Argument

6201
60

A CDE B

1 1 0 010 000 0 0 1
0 0 0 000 1 1 0 000

To s p e c i f y a f i e l d from 1 0 t o 1 7 , u s e b i t s CDE a n d
format o f t h e i n s t r u c t i o n is

set

bit

B o

The

CDF o r CIF n4
where
n4

i s a n o c t a l number t h a t PAL8 O R s w i t h
code

the

instruction

i s a n o c t a l v a l u e from 0 t o 7 ( b i t s CDE)

is a n o c t a l v a l u e i n d i c a t i n g a f i e l d r a n g e o f 10 t o
( s e t s b i t B)

For example, t h i s i n s t r u c t i o n

i n d i c a t e s f i e l d 16.
Keep i n mind t h a t t o c a l l f o r f i e l d s a b o v e f i e l d 7 ( a b o v e 32K) w i t h
CDF a n d C I F , y o u m u s t f i r s t l o a d t h e KT8A E x t e n d e d Mode R e g i s t e r w i t h
t h e LXM i n s t r u c t i o n . F o r e x a m p l e , t h e f o l l o w i n g c o d e d e p o s i t s ( 7 7 7 7
i n field 12, location lUOOÃ
LXM
CDF 24
TAD (7777
DCA I (1000

To s p e c i f y a f i e l d from 20 t o 2 7 , u s e b i t s CDE a n d
format is

set

bit

The

CDF o r CIF I n 0
where
In0
1

i s a n o c t a l number t h a t PAL8 O R s w i t h t h e i n s t r u c t i o n

i s a n o c t a l v a l u e i n d i c a t i n g f i e l d r a n g e 20 t o 27 ( s e t s
A)

i s a v a l u e from 0 t o 7 ( b i t s C D E )

For example, t h i s i n s t r u c t i o n
CDF I60

i n d i c a t e s f i e l d 26.

To s p e c i f y a f i e l d from 30 t o 3 7 , u s e b i t s CDE a n d s e t b i t
The f o r m a t i s

and

CDF o r CIF l n 4
where
ln4

i s a n o c t a l number t h a t PAL8 ORS w i t h t h e i n s t r u c t i o n

1.. . 4

a r e o c t a l v a l u e s i n d i c a t i n g a f i e l d r a n g e o f 30
( s e t b i t s A a n d B)

i s a n o c t a l d i g i t i n t h e r a n g e 0 t o 7 ( b i t s CDE)

For e x a m p l e , t h i s i n s t r u c t i o n

s p e c i f i e s f i e l d 36
One way t o a v o i d c o n f u s i o n w i t h t h i s u n u s u a l b i t c o n f i g u r a t i o n
d e f i n e h i g h f i e l d s w i t h c o n v e n i e n t mnemonics.
For example:

The ABSLDR
The ABSLDR w i l l l o a d i n f o r m a t i o n i n t o a n y f i e l d
3.2.3
However, t h e
from 0 t o 3 7 t h a t you s p e c i f y i n t h e FIELD pseudo-op.
ABSLDR o p t i o n / n i s r e s t r i c t e d t o f i e l d s 0 t o 7 o n l y .

The = f f n n n n o p t i o n s e t s t h e s t a r t i n g a d d r e s s o f t h e p r o g r a m i n memory
t o f f n n n n , w h e r e f f i s a f i e l d from 0 t o 3 7 and nnnn i s a l o c a t i o n .
I f you o m i t t h e o p t i o n o r s p e c i f y 0 , t h e ABSLDR i n s e r t s a s t a r t i n g
a d d r e s s o f 0200 i n f i e l d 0 .

3.3

Determining Memory-Size at Run-Time

I t is f r e q u e n t l y h e l p f u l
t o know t h e amount o f memory c u r r e n t l y
a v a i l a b l e t o t h e p r o g r a m you a r e r u n n i n g . The s u b - r o u t i n e i n F i g u r e 1
d e t e r m i n e s t h e amount o f memory a v a i l a b l e i n a 128K s y s t e m a t
run-time.
The p r o g r a m r e t u r n s a v a l u e i n t h e r a n g e o f 0 t o 40 t o
i n d i c a t e t h e f i r s t non-existent f i e l d i n t h e system.

To u s e t h i s r o u t i n e a b o v e 32K, you m u s t f i r s t l o a d t h e E x t e n d e d Mode
R e g i s t e r w i t h t h e LXM i n s t r u c t i o n . F o r c o m p l e t e i n f o r m a t i o n o n t h e
E x t e n d e d Mode R e g i s t e r , see t h e KT8A Memory Management C o n t r o l U s e r ' s
Guide.

/SUBROUTINE

T O D E T E R M I N E MEMORY S I Z E
/SUBROUTINE

PAL8-V1OA

04-AUG-78

T O D E T E R M I N E MEMORY S I Z E

/ T H I S S U B R O U T I N E WORKS ON ANY P D P - 8 F A M I L Y
/COMPUTER. T H E V A L U E , FROM 1 T O 4 0 O C T A L ,
/ O F THE F I R S T N O N - E X I S T E N T MEMORY F I E L D I S
/RETURNED I N T H E A C .
/NOTE

-- T H I S R O U T I N E MUST BE PLACED I N F I E L D 0

CORE,

0
CLA C L L
COR0,
CDF U
TAD
CORS I Z
AND
COR37
CLL RTR
RTR
BSW
SZL
TAD
C4
AND
COREX
DC A
+1
COR1,
CDF
TAD I
CORLOC
COR2,
NOP
DCA
COR1
TAD
COR2
DCA I
CORLOC
COR37,
37
TAD I
CORLOC
CORX,
74U0
TAD
CORX
TAD
CORV
SZA CLA
JMP
COREX
TAD
.
CORl
DCA I
CORLOC
ISZ
CORSIZ
JMP
CORO
COREX,
CDF
TAD
CORSIZ
JMP I
CORE
CORLOC, CORX
CORV,
14UU
CORSIZ, 1
c4,
4

/ ( N E E D E D FOR P D P - 8 L )
/GET F I E L D TO T E S T
/MASK U S E F U L B I T S
/TRANSFORMS
/ " 3 7 " TO " 1 7 4 "
/FOR CDF

/ S E T UP C D F T O F I E L D
/CDF I S P R O C E S S E D HERE
/SAVE CURRENT C O N T E N T S
( H A C K FOR P D P - 8 I )
1'7000

I S A "GOOD"

PATTERN

/ (HACK FOR P D P - 8 . ,NO-OP)
/TRY T O READ BACK 7 0 0 0
/ (HACK FOR P D P - 8 . , NO-OP)
/GUARD A G A I N S T "WRAP-AROUND''
/TAD ( 1 4 0 0 )
/NON-EXISTENT
FIELD EXIT
/ R E S T O R E CONTENTS DESTROYED
/TRY

NEXT H I G H E R F I E L D

/ L E A V E W I T H DATA F I E L D 0
/ 1 S T NON-EXISTENT F I E L D
/ A D D R E S S T O T E S T I N EACH F I E L D
/7UUU+74UO+1400=0
/CURRENT F I E L D TO T E S T

F i g u r e 1 Memory-Size S u b r o u t i n e

3.4

The VXAO Extended-Memory Device

The VXAO d e v i c e h a n d l e r e n a b l e s you t o u s e t h e e x t e n d e d memory
p r o v i d e d by t h e KT8A a s t h o u g h i t were a s e p a r a t e d e v i c e . You c a l l
VXAO i n t h e same way t h a t you c a l l a n y s y s t e m d e v i c e .
For e x a m p l e ,
t h i s command

c o p i e s a program c a l l e d SAMPLE i n t o an a r e a o f memory a b o v e 32K words.
The VXAO d e v i c e p r o v i d e s h i g h s p e e d 1/0 f o r u s e r s w i t h d i s k e t t e s o r
u s e r s who want t h e p e r f o r m a n c e o f a f i x e d - h e a d d i s k t y p e o f s t o r a g e
device.

3.5

The SAVECB Program

SAVECB i s a d e m o n s t r a t i o n program t h a t e n a b l e s you t o a l t e r t h e
c o n t e n t s of a program's Core C o n t r o l Block.
You w i l l f i n d t h i s
r o u t i n e u s e f u l i n a SAVE w i t h arguments i n v o l v i n g more f i e l d s i n
memory than you can s p e c i f y i n a s i n g l e SAVE command l i n e . T h i s i s
l i k e l y t o happen i n systems w i t h 128K words of memory, s i n c e t h e
number of f i e l d s you may w i s h t o s p e c i f y i n c r e a s e s from 10 t o 4 0
(octal)

The format f o r summoning SAVECB i s
R SAVECB

* fi.le.SV

where
file.SV

i s t h e name of
change

program

whose

CCB

you

want

SAVECB responds with a number s i g n ( # ) t o i n d i c a t e t h a t i t i s ready t o
a c c e p t one of t h e f o l l o w i n g commands.
TYPE

d i s p l a y s c o r e c o n t r o l block of f i l e . S V

Affmmmm- f fnnnn

adds segment t o CCB

Sffmmmm-ffnnnn

s u b t r a c t s segment from CCB

To e x i t from t h e program, t y p e

T h i s w r i t e s t h e updated Core C o n t r o l Block o n t o t h e system a r e a of t h e
device.
I n o r d e r t o change t h e program's CCB, you must l o a d t h e
program with t h e R command ( t y p i n g CTRL/C t o a b o r t e x e c u t i o n ) and then
c r e a t e a memory-image f i l e w i t h SAVE.
For example, assume you want t o s a v e segments of program FLOP.SV a s a
memory-image
f i l e c a l l e d FLAP.SV.
F i r s t , you modify t h e CCB w i t h
SAVECB

SAVECB responds w i t h a number s i g n
program, t y p e

(#).

To i n s p e c t t h e

CCB

SAVECB d i s p l a y s t h e s t a r t i n g l o c a t i o n of t h e program, i t s
Word, and t h e segments i n memory t h a t i t u s e s .
START=0000

Job

JSW:.-:2000

CORE SEGMENTS:

040200-040377~020200-020377~016400-017377~000000-007577

To add segments t o t h e CCB, e n t e r them a f t e r t h e prompt.
#A30200--30600~40600-40777
-

your

Status

Now examine the CCB again.

To place this core control block in the system
type @ after the prompt*

area

the

device,

To make a memory-image file of the segments specified in the CCB run
FLOP.SV with the R command aborting execution with CTRL/C. Then save
the segments under the new name with a SAVE command without arguments.
t

R FYI...OP t SV

S A V E FLAP t SU

To change a segment, first subtract the entire segment with
command. Then enter the altered version with the A command.

4.0

the

THE RX02 DUAL-DENSITY DISKETTE

The OS/8 V3D Device Extensions include system and non-system handlers
for RX01 and RX02, the devices for single-density and double-density
diskettes. The new handlers run on both RX01 and RX02 hardware.
NOTE
The old OS/8 handlers,
including
BOOT/RX, will not run on RX02.
An
RX02
with
hardware switch
an RX01.

4.1

a
single-density
set is identical to

RX02 Device Names

To specify an RX02 diskette in an OS/8 command line, enter
device names you use for RX01.
OS/8 recognizes the
permanent names.

the same
following

DSK

Default output device, usually same as SYS

SYS

System device, usually the diskette in drive 0

RXAO

The diskette in drive 0

RXA1

The diskette in drive 1

SYS i s m o s t a c c u r a t e l y d e f i n e d a s t h e d e v i c e t h a t
you
have
However, t h e
bootstrapped.
T h i s is u s u a l l y t h e d e v i c e i n d r i v e 0.
h a r d w a r e w i l l a l s o b o o t s t r a p a d e v i c e i n d r i v e 1, making SYS a n d DSK
e q u i v a l e n t t o RXA1.
The p e r m a n e n t names RXAO and R X A l r e m a i n
unchanged.

4.2

F o r m a t t i n g D i s k e t t e s f o r RX02

D i s k e t t e s a r r i v e from t h e f a c t o r y a l r e a d y f o r m a t t e d f o r u s e i n a
single-density
RX01 d r i v e .
To f o r m a t them f o r RX02, u s e t h e RXCOPY
p r o g r a m w i t h t h e /D o p t i o n , s p e c i f y i n g t h e d i s k e t t e you w a n t t o
re-format
a s an o u t p u t device.
( I f you e n t e r a d e v i c e by i t s e l f i n
t h e command l i n e , RXCOPY c o n s i d e r s i t t o b e a n o u t p u t d e v i c e . )
D i s k e t t e s f o r m a t t e d f o r t h e RX02 d e v i c e c o n t a i n
t h e d i r e c t o r y ) i n a 1 2 - b i t mode.

4.3

981

blocks

(besides

RX01 a n d RX02 C o m p a t i b i l i t y
double-density
system
double-density
drive.
r e q u i r e s a n RX01 d r i v e .

diskette runs
Similarly,
a

o n l y on an
single-density

RX02
SYS

RX02 a c c e p t s b o t h s i n g l e - d e n s i t y and d o u b l e - d e n s i t y non-system
diskettes.
The non-system
h a n d l e r d e t e r m i n e s which kind o f
d e v i c e i t i s d e a l i n g w i t h and p r o c e e d s a c c o r d i n g l y .
hardware
accepts
single-density use.

only

RXU1

diskettes

formatted

for

NOTE
I f you p l a c e a n RX02 d i s k e t t e on a n RX01
d r i v e , you c a n c u r r e n t l y w r i t e t o i t
without producing an e r r o r
message.
Avoid t h i s p r o c e d u r e , a s i t r e s u l t s i n a
'mixed" diskett-e.

and d o u b l e - d e n s i t y d i s k e t t e s -- b o t h
Table 6 matches single-density
s y s t e m and non-system -- w i t h t h e d r i v e s t h a t t h e y r u n o n .
Table 6
RXU1-RXU2 C o m p a t i b i l i t y

Single density
S i n g l e - d e n s i t y System

Double d e n s i t y

Double-density System

x
x
x

Table 8
OS/8 Double D e n s i t y D i s k e t t e I n t e r l e a v e Scheme
OS/8 L o g i c a l Block ( o c t a l )

Diskette Sectors (Track/secto~--decimal)

OS/8 d o e s n o t use Track O f and you c a n n o t
mode.

4.5

access

the

12-bit

Using RXCOPY with RX02

RXCOPY c o p i e s b o t h s i n g l e - d e n s i t y and d o u b l e - d e n s i t y

d i s k e t a t e s on RXO2
I f t h e o u t p u t d i s k e t t e d o e s n o t match t h e i n p u t d i s k e t t e !
RXCOPY w i l l re-format i t t o t h e p r o p e r d e n s i t y .

drives.

I n d e f a u l t mode! RXCOPY compares t h e two d i s k e t t e s f o r i d e n t i c a l
c o n t e n t s b e f o r e i t makes a copy. For a q u i c k e r t r a n s f e r ! u s e t h e /N
o p t i o n ! which i n h i b i t s t h e comparison.
For d o u b l e - d e n s i t y
t r a n s f e r s i n v o l v i n g a comparison o f c o n t e n t s !
w i l l use 16K words o f memory i f i t i s a v a i l a b l e on t h e system
f o r f a s t e r o p e r a t i o n . I f p o s s i b l e f u s e t h e MEMORY command *to p r o v i d e
t h e n e c e s s a r y memory.

RXCOPY

4.5.1
F o r m a t t i n g D i s k e t t e s w i t h MCOPY
RXCOPY w i t h t h e /S and /D
o p t i o n f o r m a t s d i s k e t t e s f o r s i n g l e - d e n s i t y o r d o u b l e - d e n s i t y use. To
format a d i s k e t t e f e n t e r i t by i t s e l f i n t h e command l i n e f f o l l o w e d by
(RXCOPY c o n s i d e r s a d e v i c e e n t e r e d by i t s e l f t o be an
the option.
output device.)
For examplef t h e f o l l o w i n g command sequence r e - f o r m a t s t h e d i s k e t t e i n
d r i v e 1 from s i n g l e - d e n s i t y t o d o u b l e - d e n s i t y .

To change i t back t o s i n g l e - d e n s i t y f t y p e

RXCOPY O p t i o n s - RXCOPY p r o v i d e s t h e f o l l o w i n g o p t i o n s .
RXCOPY p a u s e s and w a i t s

f o r user response
To c o n t i n u e ! t y p e Y.

after transfers.

before

RXCOPY t r a n s f e r s t h e c o n t e n t s o f one d i s k e t t e t o

and

another

b u t d o e s n o t check f o r i d e n t i c a l c o n t e n t s .
RXCOPY c h e c k s b o t h d i s k e t t e s f o r i d e n t i c a l c o n t e n t s and
l i s t s t h e a r e a s t h a t do n o t match b u t p e r f o r m s no
transfer.
RXCOPY r e a d s e v e r y b l o c k on t h e i n p u t

device

and

lists

bad s e c t o r s b u t p e r f o r m s no t r a n s f e r .
RXCOPY p r i n t s i t s c u r r e n t v e r s i o n number.
RXCOPY f o r m a t s t h e d i s k e t t e s p e c i f i e d a s an o u t p u t d e v i c e

t o single-density.
RXCOPY f o r m a t s

the

diskette

specified

for

output

double-density.
T h i s o p t i o n i s e q u i v a l e n t t o d e f a u l t copy and match.

5.U

THE F&Ol

DISK

T h i s s e c t i o n d e s c r i b e s v t h e b o o t i n g f f o r m a t t i n g and b u i l d i n g of
the
RLOl
d i s k pack w i t h t h e OS/8 O p e r a t i n g Systemf u s i n g t h e R L O l OS/8

s o f t w a r e s u p p o r t package.

The RLOl d i s k pack -- a h i g h - d e n s i t y mass s t o r a g e d e v i c e -- u t i l i z e s
bad-block mapping.
Bad b l o c k s o c c u r d u r i n g t h e manufacture o f d i s k s
o r d e v e l o p a s a r e s u l t of use and age. Bad b l o c k s t h a t a r e p r e s e n t
a f t e r manufacture a r e r e c o r d e d i n f a c t o r y - w r i t t e n l i s t s . Each d i s k
The RLFRMT f o r m a t t e r program
p r e s e r v e s i t s own i n d i v i d u a l l i s t .
d e t e c t s and l i s t s new bad b l o c k s t h a t occur d u r i n g d i s k o p e r a t i o n i n
t h i s allows
t h e f i e l d . Each R L O l d i s k m a i n e t a i n s up t o 4 5 bad b l o c k s ;
t h e l i f e o f t h e d i s k t o be prolonged a s a mass s t o r a g e d e v i c e .
The R L O l r e q u i r e s a PDP-8AfEfF o r M w i t h a t l e a s t 12K of memory.
Non-omnibus
PDP-8 f a m i l y computers a r e n o t hardware-compatible w i t h
the RLOl.

System and non-system R L O l h a n d l e r s a r e s t a n d a r d two-page OS/8
handlers*
Two-page h a n d l e r s r e q u i r e 12K o f memory b e c a u s e t h e second
p a g e o f t h e h a n d l e r r e s i d e s i n t h e l a s t page o f f i e l d 2 .
BATCH may b e r u n u s i n g R L O l d i s k s f e v e n on a s y s t e m w i t h 12K w o r d s
memory. Howeverf d i s k f o r m a t t i n g c a n n o t b e d o n e under BATCH.

T h i s s e c t i o n i n c l u d e s a s y s t e m d e s c r i p t i o n f d e t a i l i n g d i s k f RL8A
c o n t r o l l e r and s o f t w a r e f o r m a t s . I n a d d i t i o n f i t c o n t a i n s b o o t s t r a p
p r o c e d u r e s and
operating
instructionsf
including
a
detailed
p r e s e n t a t i o n o f messages t h a t a r e g e n e r a t e d d u r i n g d i s k f o r m a t t i n g .

5.1

System D e s c r i p t i o n

The R L O l d i s k pack h a s t h r e e l o g i c a l " d e v i c e s " t h a t a r e d e s i g n a t e d a s
F i g u r e 2-1 shows d e v i c e d e s i g n a t i o n
D e v i c e A f D e v i c e B and D e v i c e C .
on a n RLOl d i s k .
The OS/8 D e v i c e E x t e n s i o n s p r o v i d e f o r t h e s t a n d a r d OS/8 System and
110 t r a n s f e r o f 1 t o 3 2 ( d e c i m a l ) memory p a g e s t o o r from
Non-System
any o n e o f t h r e e R L O l " d e v i c e s 1 ' . The l ' d e v i c e s l l a r e l o c a t e d on any o n e
of f o u r R L O l d i s k d r i v e s .
D i s k data-space

c o n s i s t s o f 777 ( o c t a l ) t r a c k s . A s shown i n F i g u r e 2 f
d a t a on a s i n g l e t r a c k i s made up o f 40 e q u a l l e n g t h s e c t o r s numbered
T h i s r e s u l t s i n 20 ( d e c i m a l ) b l o c k s
four
0 t h r o u g h 47 ( o c t a l )
a s s i g n e d t o Device C and 1 6 t o D e v i c e A o r B.

DISK D A T A SPACE

ET
TRACK o

777

ONE RLOl TRACK

16 20

ODD SECTORS

EVEN SECTORS
46 1

4 BLOCKS

16 BLOCKS

AOR B

Track and Sector numbers are octal
Block numbers are decimal

Figure 2

D e v i c e s A f B f C on RLOl D i s k

A p p r o x i m a t e l y 10fOOO ( d e c i m a l ) OS/8 b l o c k s a r e s u p p o r t e d p e r d r i v e f
4 0 % a s D e v i c e A f 40% a s D e v i c e B f and 20% a s D e v i c e C.
T h i s scheme
p r o v i d e s some u s e r c o n t r o l o v e r t h e t r a d e o f f between t h e number o f
d e v i c e s and t h e l e n g t h o f e a c h d e v i c e .
D e v i c e C h a s a d i f f e r e n t l e n g t h from D e v i c e s A and B.
In generalf
D e v i c e C i s used o n l y when a maximum amount o f d a t a i s t o b e s t o r e d on
the disk.

Each d e v i c e s u p p o r t s up t o 1 5 ( d e c i m a l ) bad b l o c k s t o p r o v i d e
bad-block mapping*
T h e s e b l o c k s may b e t h o u g h t o f a s p pares"^ and
s h o u l d n e v e r b e a c c e s s e d by t h e u s e r This support
involves
" i n v i s i b l e " mapping o f OS/8 b l o c k numbers i n t o t h e s e t o f a c t u a l good
d i s k b l o c k s ; no u t i l i t y program need b e changed ( i n c l u d i n g SQUISH)
and u s e r a w a r e n e s s o f t h i s f e a t u r e i s n o t r e q u i r e d * Bad-block l i s t s
a r e kept r e s i d e n t t o reduce t h e e x t r a reads required*
Bad-block l i s t s t h a t o c c u r d u r i n g d i s k m a n u f a c t u r e a r e m a i n t a i n e d i n
f a c t o r y - g e n e r a t e d l i s t s which a r e s t o r e d on t r a c k 777 o f t h e d i s k *
The OS/8 s y s t e m p r e s e r v e s f i v e c o p i e s o f t h e f a c t o r y l i s t ! a l l o f
which a r e i d e n t i c a l *
When a d i s k i s i n i t i a l l y f o r m a t t e d u s i n g OS/8, t h e f o r m a t t i n g program
(RLFRMT) a s c e r t a i n s t h a t t h e d i s k i s new* The program t h e n r e a d s i n
t h e f a c t o r y l i s t ! and c h e c k s t h e d i s k f o r any new bad b l o c k s *
The
f a c t o r y l i s t and t h e new bad-block l i s t a r e t h e n combined! and! a f t e r
t h e u s e r ' s go-ahead! t h e f o r m a t t i n g program w r i t e s t h e n e w l y - g e n e r a t e d
OS/8 bad-block l i s t o n t r a c k 0 o f t h e d i s k *
When r u n n i n g OS/8! you may g e n e r a t e a n 110 e r r o r b e c a u s e o f a bad
block*
You c a n c h e c k t h i s by a g a i n r u n n i n g t h e f o r m a t t e r program.
RLFRMT a s c e r t a i n s t h a t t h e d i s k i s a l r e a d y f o r m a t t e d , s o i t r e a d s i n
t h e p r e v i o u s OS/8 bad-block l i s t and c h e c k s t h e d i s k f o r a n y new bad
b l o c k s * When you i n s t r u c t i t t o p r o c e e d ! t h e f o r m a t t i n g program
writes t h e u p d a t e d OS/8 bad-block l i s t on t r a c k 0 o f t h e d i s k * You
s h o u l d n o t a l l o w t h e bad b l o c k l i s t t o b e w r i t t e n i f a n u n e x p e c t e d l y
l a r g e number o f bad b l o c k s a r e r e p o r t e d ; f o r m a t t i n g t o remove bad
b l o c k s i s a permanent! i r r e v e r s i b l e p r o c e d u r e *
D u r i n g a n 110 t r a n s f e r ! t h e h a n d l e r f i r s t r e a d s i n t h e OS/8 bad-block
list f o r the device*
The s y s t e m e f f e c t i v e l y maps a r o u n d t h e bad
blocks*
T h i s h a s t h e e f f e c t o f making them a p p e a r
to
have
d i s a p p e a r e d ! s o t h a t s t a n d a r d OS/8 b l o c k numbers c a n b e u s e d *
A l l p e r m a n e n t i n f o r m a t i o n s t o r e d o n R L O l d i s k p a c k s ( s u c h a s bad-block

l i s t s ) i s p r o t e c t e d from d e s t r u c t i o n by OS/8 h a n d l e r c a l l s by b e i n g
" o u t e i d e o f " t h e OS/8 d a t a s p a c e *

An a n n u l u s d a t a scheme r e d u c e s t h e a v e r a g e i n t r a - d e v i c e s e e k time*
T h i s means t h a t d a t a c o n t i n u e s from t h e t r a c k o n s u r f a c e 0 t o t h e
t r a c k on s u r f a c e 1 f o r each c y l i n d e r *
The b o o t s t r a p r o u t i n e i s under 32 ( d e c i m a l ) words i n
s u i t a b l e f o r ROM i m p l e m e n t a t i o n and/or d i r e c t t o g g l e - i n *
Three t r i e s (two
reported.

retries)

are

attempted

before

numbers

NOTE
Unless o t h e r w i s e noted! a l l
t h i s section are octal.

length,

and

error

110

5.1.1

Disk Format - The format of t h e R L O l d i s k i s a s follows:

Track

Sector

Contents
Reserved f o r f u t u r e use by D I G I T A L
Reserved f o r f u t u r e use by D I G I T A L
Reserved f o r f u t u r e use by D I G I T A L
Reserved f o r f u t u r e use by D I G I T A L
Reserved f o r f u t u r e use by D I G I T A L
Reserved f o r f u t u r e use by D I G I T A L
Bad Block L i s t s f o r Devices A and B
Bad Block L i s t f o r Device C
Device A , Block 0 ( f i r s t h a l f )
Device A , Block 0 (second h a l f )

Device C , Block 0 ( f i r s t h a l f )
Device C , Block 0 (second h a l f )

Device B , Block 0 ( f i r s t h a l f )
Device B , Block 0 (second h a l f )

D i s k Pack S e r i a l Number, L i s t

of Manufacturing-Detected Bad S e c t o r s
and Field-Detected Bad S e c t o r s .
NOTE

c o n t a i n s complete d e s c r i p t i o n s
of bad block l i s t formats a s comments a t
t h e s t a r t of t h e program.

RLFRMT.PA

5.1.2
RL8A Controller Format - The
software c o n t r o l of t h e system.

following

registers

perform

Memory Address R e g i s t e r :
The Memory Address R e g i s t e r i s a 1 2 - b i t r e g i s t e r t h a t c o n t a i n s
l o c a t i o n a t which t h e f i r s t t r a n s f e r i s t o be performed.

Memory address

Memory Address Register

the

Word Count R e g i s t e r :
The Word Count R e g i s t e r i s a 1 2 - b i t r e g i s t e r t h a t c o n t a i n s
n e g a t i v e of t h e number of words t o be t r a n s f e r r e d a t one time.

Word count

the

_f
Word Count R e g i s t e r

Sector Address R e g i s t e r :
The S e c t o r Address R e g i s t e r c o n t a i n s t h e
through 5.

Sector address

sector

address

bits

2
Sector Address R e g i s t e r

Command R e g i s t e r A:
Command R e g i s t e r A c o n t a i n s t h e d i r e c t i o n ,
address. I t has t h e following format:

surface

and

cylinder

Direction
0: towards lower cylinder
addresses (outside)
1 : towards higher cylinder
addresses (inside)
Surface
0: upper surface
1: lower surface
Cylinder address
(or cylinder difference)

Command R e g i s t e r A
Command Register B:
Command Register B d e s i g n a t e s maintenance mode, byte mode, i n t e r r u p t
e n a b l e , d r i v e s e l e c t , memory f i e l d and f u n c t i o n . I t has t h e following
format.

Maintenance mode
Byte mode
0: truncated
1: byte
Interrupt enable
Drive select
Memory field
Function
0: maintenance
1 : reset drive errors
2: get drive status
3: seek
4: read next header
5: write
6: read
7: read, no header check

_____I

Command Register B
5.1.3
I n s t r u c t i o n S e t - The following i n s t r u c t i o n s o p e r a t e
system.

the

disk

Note t h a t t h e AC i s c l e a r e d a f t e r a t r a n s f e r from t h e AC t o a r e g i s t e r
i n t h e c o n t r o l l e r . Also, t h e AC i s c l e a r e d f i r s t before a t r a n s f e r i s
made from a c o n t r o l l e r r e g i s t e r t o t h e AC.
The s k i p i n s t r u c t i o n s a r e s k i p and then c l e a r I O T ' s ;
that is, i f a
given c o n d i t i o n ( f u n c t i o n done) i s t r u e , t h e function-done f l a g w i l l
be c l e a r e d a t t h e completion of t h e s k i p IOT.
Octal Code

Mnemonic

Function

RLDC

Clear d e v i c e , a l l r e g i s t e r s , AC and f l a g s
not use t o t e r m i n a t e a d i s k f u n c t i o n )

RLSD

S k i p on f u n c t i o n done f l a g , then c l e a r i t

RLMA

Load memory a d d r e s s r e g i s t e r from AC

RLCA

Load command r e g i s t e r "A" from AC

RLCB

Load command r e g i s t e r
command

RLSA

Load s e c t o r address r e g i s t e r from AC b i t s 0-5

----

Spare ( w i l l c l e a r t h e A C )

RLWC

Load word count r e g i s t e r from AC

RRER

Read e r r o r r e g i s t e r i n t o AC b i t s 0-2 and 11

RRWC

Read word count r e g i s t e r i n t o AC

RRC A

Read command r e g i s t e r "A" i n t o AC

"B"

from

AC,

(do

execute

O c t a l Code

Mnemonic

6613

RRC B

Read command r e g i s t e r "B"

6614

RRSA

Read s e c t o r a d d r e s s r e g i s t e r i n t o AC b i t s 0-5

6615

RRS I

Read ( s i l o ) word ( 8 - b i t )

6616

----

S p a r e ( d o e s n o t c l e a r AC)

6617

RLS E

S k i p on c o m p o s i t e e r r o r f l a g , t h e n c l e a r i t

5.1.4
OS/8 Data S p a c e
and C i s a s f o l l o w s :

Function
i n t o AC

i n t o AC b i t s 4-11

- The l a y o u t o f OS/8 d a t a s p a c e on

Devices

- Use

the

D e v i c e s A and B

- Track
-

Block

Sectors

Device C
Block
Track
-

Sectors

5.1.5
C o n v e r t i n g Block Numbers t o Hardware D i s k
following procedures.

Addresses

For D e v i c e s A and B:

The s e c t o r a d d r e s s i s 4 t i m e s t h e s e c t o r code minus 27.
a d d r e s s i s n e g a t i v e , add 47.

If the sector

D e v i c e A h a s MSB o f c y l i n d e r = 0 ( c y l i n d e r s 0 - 1 7 7 ) .
D e v i c e B h a s MSB o f c y l i n d e r = 1 ( c y l i n d e r s 2 0 0 - 3 7 7 ) .
T h e b l o c k number s o f t w a r e f o r m a t f o r D e v i c e s A a n d B i s shown
following diagram.

the

BLOCK NUMBER:

LSB OF CYLINDER

B l o c k Number F o r m a t f o r D e v i c e s A a n d B
F o r D e v i c e C:
T h e s e c t o r a d d r e s s i s 4 times t h e s e c t o r c o d e .
The t r a c k i s o n e p l u s
t h e t r a c k code.
T r a c k s 0 and 777 c a n n o t b e a d d r e s s e d ;
t h i s ensures
t h e i n t e g r i t y o f t h e f a c t o r y - d e t e c t e d a n d OS/8 b a d - b l o c k l i s t s , w h i c h
reside on these tracks.
T h e b l o c k number

software

format

for

Device

shown

the

shown

the

following diagram.

BLOCK NUMBER:
TRACK CODE

B l o c k Number F o r m a t f o r D e v i c e C
T h e t r a c k s o f t w a r e f o r m a t f o r D e v i c e s A , B, a n d
following diagram.

TRACK:
CYLINDER ADDRESS

R
F
A

T r a c k F o r m a t f o r D e v i c e s A , B, and C

5.2

Handler D e s c r i p t i o n

The s t a n d a r d OS/8 d e v i c e d e s i g n a t i o n f o r m a t c a n n o t b e u s e d w i t h t h e
t o represent
RL01.
N o r m a l l y , t h e s t a n d a r d f o r m a t would u s e "RLAO:
D e v i c e A o f u n i t ( d r i v e ) 0 . The s i n g l e - w o r d f o r m a t u s e d i n t e r n a l l y t o
s t o r e d e v i c e names d o e s n o t d i s t i n g u i s h between 'IRK" d e v i c e s and "RL"
d e v i c e s , r e s u l t i n g i n e r r o n e o u s RESORC r e p o r t s , and
in
other
a n o m a l i e s . The RL01 t h e r e f o r e u s e s "RLOA" t o r e p r e s e n t u n i t 0 , D e v i c e
A , and s o f o r t h .
T a b l e 9 p r o v i d e s i n f o r m a t i o n on t h e RL01 h a n d l e r s .
SYS i s t h e same d e v i c e a s RLOA ( D r i v e 0 , D e v i c e A )

Table 9
RL01 H a n d l e r I n f o r m a t i o n
Device
Name

Entry
Point
Offset
(Octal)

File
Name
(Group
Name)

SYS

RLSY

RLOA
RLOB
RLOC
RL1A
RL1B
RL1C

RLO
RLO
RLC
RLl
RL1
RLC

RL2A
RL2B
RL2C
RL3A
RL3B
RL3C

RL2
RL2

Device
Type

Device
Code
(Octal)

Octal
Length
(Blocks)

Decimal
Length
(Blocks)

RLC

RL3
RL3
RLC

A b r i e f d e s c r i p t i o n o f RL01 h a n d l e r o p e r a t i o n is a s f o l l o w s :

When i n i t i a l l y c a l l e d , e a c h RL01 h a n d l e r e x e c u t e s o n c e - o n l y
c o d e t o r e a d i n t h e bad b l o c k l i s t f o r i t s d r i v e . The
h a n d l e r e r r o r r e t u r n i s t a k e n ( w i t h AC=4000) i f a n 1/0 e r r o r
o c c u r s o r i f t h e b a d - b l o c k l i s t i s found t o b e i n v a l i d ( a
v a l i d bad-block l i s t b e g i n s w i t h a s p e c i a l i d e n t i f i c a t i o n
code)

G e t handler arguments.

Map e a c h b l o c k t o b e t r a n s f e r r e d a r o u n d bad b l o c k s b y
i n c r e m e n t i n g t h e b l o c k number o n c e f o r e a c h bad b l o c k ( a s
l i s t e d i n t h e bad-block l i s t f o r t h e r e q u e s t e d d e v i c e ) less
t h a n o r e q u a l t o t h e p r e s e n t b l o c k . T h i s p r o c e d u r e makes bad
blocks e f f e c t i v e l y "disappear."

Transfer one page/sector a t
number o f p a g e s .

I f a n 1/0 e r r o r o c c u r s f o r a n y RL01 r e a d o r write o p e r a t i o n ,
r e t r y twice t h e n t a k e t h e S y s t e m o r Non-System H a n d l e r e r r o r
r e t u r n w i t h AC=4000.

time,

the

requested

5.3

Loading and B o o t s t r a p Procedure

The f o l l o w i n g s e q u e n c e o f o p e r a t i o n s o c c u r s
t h e RL01.

during

bootstrapping

BOOT-1, t h e p r i m a r y b o o t s t r a p r o u t i n e , i s r e a d i n t o l o c a t i o n s
00001-00035
f r o m a ROM, f r o m BOOT.SV, o r t o g g l e d i n t h r o u g h
BOOT-1
the console switches.
The s t a r t i n g a d d r e s s i s 00001.
c l e a r s D r i v e 0 a n d r e a d s a n d s t a r t s BOOT-2.
I f a n 1/0 e r r o r
o c c u r s , BOOT-1 w i l l r e p e a t u n t i l i t i s s u c c e s s f u l .

BOOT-2 o c c u p i e s l o c a t i o n s 00000-00177.
BOOT-2 r e a d s t h e OS/8
R e s i d e n t M o n i t o r i n t o t h e l a s t p a g e s o f f i e l d s 0 , 1, a n d 2 .
I f a n 1/0 e r r o r o c c u r s , BOOT-2 w i l l " h a n g " a s a n i n d i c a t i o n
of f a i l u r e t o boot.

BOOT-2 t h e n c a l l s t h e K e y b o a r d M o n i t o r b y j u m p i n g t o l o c a t i o n
07605.
NOTE
Never r e p l a c e t h e s y s t e m d i s k
pack
without rebooting;
each pack h a s i t s
own OS/8 b l o c k n u m b e r i n g s c h e m e t h a t i s
determined during formatting.

R e p l a c e non-system d i s k p a c k s o n l y a f t e r t h e Monitor d o t a p p e a r s o n
the terminal.
T h i s is done t o e n s u r e t h a t t h e bad-block l i s t r e a d by
t h e h a n d l e r is correct.

5.3.1
L o a d i n g t h e RL01 D i s k P a c k
loading a s follows:

- Prepare

RL01

Disk

S e p a r a t e t h e p r o t e c t i v e cover from t h e d i s k pack,
following steps.

Pack

for

using

the

L i f t t h e c a r t r i d g e by g r a s p i n g t h e h a n d l e w i t h t h e
hand.

S u p p o r t t h e c a r t r i d g e from u n d e r n e a t h w i t h t h e l e f t hand.

Lower t h e h a n d l e a n d p u s h t h e h a n d l e s l i d e
w i t h t h e thumb o f t h e r i g h t h a n d .

the

left

Raise t h e handle t o its u p r i g h t p o s i t i o n t o s e p a r a t e
c a r t r i d g e from t h e p r o t e c t i o n c o v e r .

the

with

the

right

P l a c e t h e c a r t r i d g e i n t h e d r i v e shroud
recess f a c i n g t h e r e a r o f t h e m a c h i n e .

Rotate the
cartridge
a
few
degrees
clockwise
and
c o u n t e r - c l o c k w i s e t o e n s u r e t h a t i t is p r o p e r l y s e a t e d w i t h i n
t h e shroud.

G e n t l y lower t h e h a n d l e t o a h o r i z o n t a l
the drive spindle.

Place t h e p r o t e c t i o n cover on t o p of t h e c a r t r i d g e .

Carefully close the drive lid.

P u s h t h e "LOAD/RUNW p u s h b u t t o n .

position

handle

engage

5.3.2
Booting from BOOT.SV - Boot from t h e BOOT.SV program
t h e BOOT o r R commands a s f o l l o w s :

using

-.BOOT

or
or

/RL
-

-.BOOT RL
.R BOOT

The f o l l o w i n g
5.3.3
B o o t i n g from t h e C o n s o l e S w i t c h e s
e n t e r s t h e b o o t s t r a p program i n t o PDP-8/A memory.

see

procedure

P r e s s i n o r d e r t h e MD and DISP
numbers a r e b e i n g d e p o s i t e d .

P r e s s , i n o r d e r , 0 and LXA t o s e l e c t memory f i e l d 0.

P r e s s , i n o r d e r , 1 and LA t o s t a r t
a d d r e s s 1.

Deposit t h e o c t a l v a l u e s given i n
v a l u e w i t h D NEXT.

Table

A f t e r a l l v a l u e s a r e d e p o s i t e d , p r e s s , i n o r d e r , 0001 and
t o a l l o w t h e program t o s t a r t a t l o c a t i o n 1.

P r e s s , i n o r d e r , INIT and RUN t o s t a r t t h e b o o t s t r a p program.

buttons

what

octal

instructions

following

each

5.3.4
ROM B o o t s t r a p Switch S e t t i n g s
Set the bootstrap
s e t t i n g s f o r R O M ' s l a b e l e d 465A2 and 469A2 a s f o l l o w s :

switch

Program

S2-5

S2-6

S2-7

S2-8

Sl-1

Sl-2

Sl-3 Memory A d d r e s s

RL8A

OFF

5.4

4000

Operating I n s t r u c t i o n s

You m u s t f o r m a t new RL01 d i s k p a c k s by r u n n i n g t h e RLFRMT program
p r i o r t o any OS/8 u s e ( i n c l u d i n g s y s t e m b u i l d i n g ) . T h i s i s r e q u i r e d
b e c a u s e RLFRMT c o n s t r u c t s and w r i t e s s p e c i a l l y f o r m a t t e d bad-block
l i s t s on t h e pack.
OS/8 RL01 o p e r a t i o n s on d i s k s t h a t have n o t been f o r m a t t e d w i t h RLFRMT
result i n error reports.
T h e r e f o r e , you s h o u l d run RLFRMT even b e f o r e
u s i n g BUILD t o b u i l d a new s y s t e m head.
Device C non-system h a n d l e r s a r e p r o v i d e d t o a c c e s s a l l a v a i l a b l e
s t o r a g e c a p a c i t y o f t h e RL01 d i s k p a c k s .
T r a n s f e r s t o o r from Device
C a r e s l o w e r t h a n t h o s e t o o r from D e v i c e s A and B.
This is so
b e c a u s e , w h i l e Device A and B u s e 80% o f e a c h t r a c k , Device C o n l y
u s e s 20% o f e a c h t r a c k ( o n l y 4 b l o c k s a r e s t o r e d on e a c h t r a c k ) .
Thus,
t h e time s p e n t i n s e e k i n g new t r a c k s w i l l be h i g h e r f o r Device

B e c a u s e d i f f e r e n t RL01 p a c k s may h a v e d i f f e r e n t p a t t e r n s o f b a d blocks,
i t i s g o o d p r a c t i c e t o e n d a n OS/8 s e s s i o n w i t h t h e m o n i t o r
"BOOT" command ( o r "R BOOT"), s o t h a t o t h e r u s e r s w i l l b e a b l e t o t y p e
'RL" t o b o o t t h e i r d i s k s . Of c o u r s e , t h i s p r o c e d u r e i s u n n e c e s s a r y i f
t h e c o m p u t e r s y s t e m h a s a h a r d w a r e b o o t s t r a p f o r t h e RL01.

D i s k Formatting - F o r m a t a l l new RL01 d i s k p a c k s p r i o r t o a n y
5.4.1
u s e u n d e r OS/8, i n c l u d i n g s y s t e m b u i l d i n g .
Mount t h e RL01 d i s k p a c k
(Section 4.2).
F o r m a t t h e RL01 d i s k b y u s i n g t h e f o l l o w i n g p r o c e d u r e :
1.

Type

t o run t h e f o r m a t t e r program.
RLFRMT Vvp i s p r i n t e d o n t h e t e r m i n a l s i g n i f y i n g t h e s t a r t o f
t h e o p e r a t i o n where:
v i s t h e v e r s i o n number
p is t h e patch l e v e l l e t t e r
t h e program t h e n prompts w i t h
DRIVE?

Type t h e d r i v e number

(0-3)

o n which t h e pack is mounted.

The f o r m a t t e r p r o g r a m t h e n r e a d s a l l b l o c k s o n t h e d i s k t o
d e t e c t a n y new b a d b l o c k s .
The p r o c e s s t a k e s 3 5 t o 40
seconds.
After t h i s period, an i n i t i a l d i s p l a y is presented
as follows:
UNFORMATTED (NEW) DISK PACK SERIAL NUMBER n n n n n n n n n n
FACTORY-DETECTED BAD BLOCKS: NONE
NEWLY-FOUND BAD BLOCKS: NONE
NEW OS/8 BAD BLOCKS: NONE
FORMAT PACK WITH THIS NEW L I S T ?
The m e s s a g e s a r e e x p l a i n e d
Messages.
3.

Table

10,

RLFRMT

Formatter

T y p e a " Y " o r " N " ( f o l l o w e d b y a RETurn) i n r e s p o n s e t o t h e
l a s t m e s s a g e "FORMAT PACK WITH THIS NEW L I S T ? " t o e i t h e r
a l l o w o r p r e v e n t t h e w r i t i n g o f t h e new OS/8 b a d - b l o c k l i s t s .
The
program s i g n i f i e s completion o f t h i s Ã o p e r a t i o n by
displaying

DONE:
KlRiVE ?

T y p e CTRL/C t o r e t u r n t o t h e OS/8 m o n i t o r .
o r designate another drive for formatting.

Remove

the

pack

The f o l l o w i n g example i l l u s t r a t e s p o s s i b l e messages t h a t may
be g e n e r a t e d d u r i n g a p a r t i c u l a r sequence o f OS/8 RL01
f o r m a t t i n g o p e r a t i o n s i f bad b l o c k s a r e found.
OS/8 (OLD) D I S K *
WARMING: ALL F--ACTORY-WRITTEN L I S T S DESTROYED*
FaREVI OUS O S / 8 BAD BL..OCKS: NONE
A
6375
NEWLY-FOUND BAD BLOCKS: A 6 3 7 4
B 4347
B 4350
C05J.4
C Q^l^
C 2073

0360

WARNING : AN ADDIT.IONAL BAD BLOCK F'OUND +
ZERO D I S K BEFORE-: USE: !
NEW OS/U

B 4347

B 0360
BAD BLOCKS: A 6 3 7 4
A 6375
B 4350
C 0514
C 0515
C 2073

FORMAT PACK WITH T H I S NEW L I S T ?

The f o r m a t t e r program t h e n w r i t e s o r d o e s n o t w r i t e s p e c i a l OS/8 bad
block l i s t s on t h e pack, depending on a "Y" o r 'IN" u s e r r e s p o n s e .
These l i s t s i n c l u d e o n l y t h e f a c t o r y - d e t e c t e d and newly-detected
bad
b l o c k s f o r new p a c k s , o r p r e v i o u s OS/8 and newly-detected bad b l o c k s
f o r o l d packs.
Warnings a r e g i v e n f o r v a r i o u s c o n d i t i o n s
as
a p p r o p r i a t e ( s e e Table l o ) , .
NOTE

R e f o r m a t t i n g a p r e v i o u s l y - u s e d d i s k pack
w i l l make any newly-detected bad b l o c k s
e f f e c t i v e l y d i s a p p e a r from t h e pack.
Any f i l e s l o c a t e d a t o r a f t e r any such
new bad b l o c k s , however, w i l l t u r n t o
g a r b a g e due t o t h e i m p l i c i t renumbering
of a l l OS/8 b l o c k s p a s t t h o s e p o i n t s .
T a b l e 10 l i s t s normal f o r m a t t e r messages, o p e r a t o r e r r o r messages, and
program e r r o r messages.
T a b l e 10
RLFRMT F o r m a t t e r Messages

Normal Messages

Message

Meaning

RLFRMT Vvp

I d e n t i f i e s s t a r t of o p e r a t i o n s .
"v" i s v e r s i o n number,
"p" i s
patch l e v e l l e t t e r .

DRIVE

Requests user t o
type
number and RETURN key.

UNFORMATTED (NEW) DISK PACK

drive

D i s k does not

c o n t a i n OS/8 bad
block l i s t s , e i t h e r because t h e
d i s k i s brand new o r because
t h e s e l i s t s have been d e s t r o y e d
by
non-DIGITAL
software
or
d i a g n o s t i c programs.
( c o n t i n u e d on n e x t page)

Table 10
(Cont.)
RLFRMT F o r m a t t e r M e s s a g e s

~ o r m a lM e s s a g e s (~0nt.)
Meaning

Message
(OLD) DISK PACK

D i s k c o n t a i n s v a l i d OS/8
bad
block lists.
(A f o r m a t t e d pack
c o n t a i n s o c t a l 0123 i n words 100
- 177 of s e c t o r 16 ( o c t a l ) of
s u r f a c e 0 of c y l i n d e r 0 ) .

SERIAL NUMBER x x x x x x x x x x

is t h e ten
The s e r i a l number
d i g i t o c t a l number
assigned t o
t h e p a c k a t time o f m a n u f a c t u r e ,

FACTORY-DETECTED BAD BLOCKS

The l i s t o f bad b l o c k s
found a t
manufacturing t i m e is p r i n t e d i n
t h e f o r m a t I'd n n n n " , w h e r e d=A, B,
o r C ( t h e d e v i c e ) and nnnn = t h e
b l o c k number o n t h a t d e v i c e w h i c h
is bad.

PREVIOUS OS/8 BAD BLOCKS

The c u r r e n t OS/8
a r e printed.

NEWLY-FOUND BAD BLOCKS

The l i s t o f bad b l o c k s j u s t f o u n d
by r e a d - c h e c k i n g t h e e n t i r e d i s k
is p r i n t e d .

NEW OS/8

T h i s l i s t r e s u l t s from combining
t h e previously p r i n t e d lists.
It
is t h e l i s t t h a t is w r i t t e n on
t h e p a c k a s t h e new OS/8 bad
block lists.

OS/8

BAD BLOCKS

bad b l o c k

lists

FORMAT PACK WITH THIS NEW LIST?

User t y p e s " Y " o r

DONE

I n d i c a t e s t h a t new OS/8 bad b l o c k
l i s t s have been w r i t t e n on t h e
pack.
The p a c k now
may
be
removed
i f desired.
"DONE" i s
a l w a y s f o l l o w e d b y "DRIVE?"
to
a l l o w f o r m a t t i n g another pack.

---

'IN"
t o allow or
p r e v e n t w r i t i n g t h e new OS/8 bad
block lists.

O p e r a t o r E r r o r Messages
Meaning

Message
PLEASE SPECIFY D R I V E NUMBER
( 0 - 3 ) ON WHICH PACK TO BE
FORMATTED I S MOUNTED.

RLFRMT c o u l d n o t i n t e r p r e t u s e r
User c a n
response
t o "DRIVE?".
t r y again.

PLEASE WRITE-ENABLE DRIVE,
THEN HIT RETURN!

w r i t e - l o c ked

RLFRMT

found

the selected drive
just
before
a t t e m p t i n g t o w r i t e new OS/8 bad
b l o c k l i s t s on t h e pack.
( c o n t i n u e d on n e x t p a g e )

T a b l e 10

(Cont.)

RLFRMT F o r m a t t e r Messages

Warning Messages ( f o r m a t t i n g can s t i l l be done)
Message

Meaning

WARNING:
AN A D D I T I O N A L BAD
BLOCK FOUND.
ZERO DISK
BEFORE USE!

I f t h e u s e r p e r m i t s t h e new OS/8
bad block l i s t s t o be w r i t t e n ,
t h e OS/8 block numbering scheme
w i l l be changed due t o a new bad
b l o c k found d u r i n g t h e read-check
of t h e e n t i r e pack. T h i s w i l l
make " g a r b a g e " o u t o f any f i l e s
l o c a t e d a t and a f t e r t h e bad
block number.

WARNING:
BAD BLOCK I N SYSTEM
AREA.
DO NOT USE AS SYSTEM

DISK!

WARNING:

ALL FACTORY-WRITTEN

LISTS DESTROYED

new bad block was found d u r i n g
t h e read-check of t h e pack. T h i s
new bad block was on Device A
between
0
and 6 6 i n c l u s i v e .
S i n c e no bad b l o c k s a r e allowed
in
t h i s a r e a f o r t h e system
d e v i c e (due
to
bootstrapping
c o n s t r a i n t s ) , p e r m i t t i n g t h e pack
t o be f o r m a t t e d d i s a l l o w s f u t u r e
use
as
a
system
device.
Non-system use i s u n a f f e c t e d .

c o p i e s of t h e m a n u f a c t u r i n g d e t e c t e d bad block l i s t and d i s k
pack
s e r i a l number have been
destroyed
by
non-Dig i t a l
software.
Formatting c o n t i n u e s ,
assuming no f a c t o r y - d e t e c t e d
bad
blocks.
All

E r r o r Messages ( f o r m a t t i n g c a n n o t be done)
Message

FATAL 1/0 ERROR

Meaning
this
message
appears
If
immediately, i t i n d i c a t e s t h a t
t h e OS/8 bad block l i s t s c o n t a i n
The pack
p h y s i c a l 1/0 e r r o r s .
s h o u l d n o t be used f u r t h e r under
OS/8.
I f t h i s message a p p e a r s
a f t e r a t t e m p t i n g t o w r i t e new
OS/8
bad
block
lists,
it
i n d i c a t e s t h a t an
1/0
error
occurred.
The most common c a u s e
w i l l be a w r i t e - l o c k e d d r i v e .

( c o n t i n u e d on n e x t page)

Table 10
(Cont.)
RLFRMT F o r m a t t e r Messages
4.

E r r o r Message ( f o r m a t t i n g c a n n o t be d o n e )

Message

(Cont.)
Meaning

CANNOT FORMAT D I S K

A l l e r r o r messages e n d w i t h t h i s
one,
to
indicate
that
the
formatting operation h a s failed.
T h i s message i s a l w a y s f o l l o w e d
by " D R I V E ? " t o a l l o w f o r m a t t i n g
another pack.

OVER 1 5 BAD BLOCKS ON
ONE DEVICE

T h e n e w O S / 8 bad b l o c k l i s t s t o
be w r i t t e n c o n t a i n more t h a n t h e
number of bad b l o c k s
maximum
supported u n d e r O S / 8 .

OVER 6 3 NEWLY-FOUND
BAD BLOCKS

I n d i c a t e s R L 0 1 h a r d w a r e problem
detected d u r i n g r e a d - c h e c k
of
d i s k o r a p a c k w i t h more t h a n 6 3
bad b l o c k s .
should
be

RL01

diagnostics

r u n and t h e d r i v e
and/or c o n t r o l l e r f i x e d b e f o r e
a t t e m p t i n g t o format d i s k p a c k s .

5.5

System Building

T h e f o l l o w i n g p r o c e d u r e i s u s e d f o r b u i l d i n g a system.

F o r m a t t h e d i s k p a c k a s described i n Section 5 . 4 . 1 .

R u n B U I L D from a n y d e v i c e .
BUILD is t h e s y s t e m g e n e r a t i o n
program
for OS/8
( s e e t h e OS/8
Handbook for a detailed
d e s c r i p t i o n of B U I L D ) .

L o a d R L S Y - B N , RLO.BN, R L l . B N , R L 2 . B N , R L 3 . B N ,
o r RLC.BN a s
desired
( s e e T a b l e 9 f o r names of d e v i c e s i n e a c h g r o u p ) .
F o r e x a m p l e , a complete s y s t e m f o r t w o d i s k d r i v e s w o u l d
i n c l u d e S Y S , RLOB, RLOC, R L l A , R L l B , and RL1C.
A partial
system t o s u p p o r t a l l f o u r d r i v e s c o u l d i n c l u d e S Y S , RLOA,
RLOB, R L l A , R L l B , R L 2 A , R L 2 B , R L 3 A , and RL3B.

Issue t h e B O O T ( s t r a p ) command.
T h i s w i l l b u i l d an RL01
s y s t e m o n RLOA, and s t a r t i t . I t t h e n a s k s a q u e s t i o n a s t o
w h e t h e r a n e w ( z e r o ) d i r e c t o r y s h o u l d be w r i t t e n o n t h e n e w
device.
A n s w e r y e s t o place a zero d i r e c t o r y on t h e d e v i c e .
RUN a l l p r o g r a m s w i t h t h e RUN c o m m a n d u n t i l moved t o t h e R L 0 1
d i s k pack.

APPENDIX A

RX02 BOOTSTRAP PROGRAM

PAL8-V10A
A C l = C L L CLA I A C
A C 2 = C L L CLA CML R T L
A C 6 = C L L CLA CML I A C R T L
A C 4 0 0 0 = C L L CLA CML RAR
A C 3 7 7 7 = C L L CLA CMA RAR
A C 7 7 7 5 = C L L CLA CMA R T L

/
/
/

NO DATE

/RX02'S

MUST RUN ON AN OMNI-BUS

D E V I C E I O T SYMBOLIC EQUATES

LCD=6751
XDR=6 7 5 2
S T R = 6 7 53
SER=6754
SDN76755

/
/
/

/LOAD COMMAND
/TRANSFER DATA
/ S K I P I F READY T O T R A N S F E R
/ S K I P ON ERROR
/ S K I P ON DONE

*20

/
READ,

TAD
UNIT
/TRY NEXT COMBINATION O F D E N S I T Y AND U N I T
TAD
C O N 3 6 0 /ADDING I N 3 6 0
AND
C O N 4 2 0 / K E E P I N G ONLY 4 2 0 B I T S
DCA
UNIT
/CYCLES 4 0 0 , 4 2 0 , 0 , 2 0 , 4 0 0 , , , , , , , ,
AC 6
/COMMAND TO READ DISK
TAD
UNIT
/ U N I T AND D E N S I T Y
LCD
/COMMAND T O CONTROLLER
/TO S E T S E C T O R AND TRACK T O 1
AC 1
J MS
LOAD
/SECTOR T O CONTROLLER, LEAVES AC ALONE
J MS
LOAD
/AND TRACK
LITRAL, 7 0 0 4
/LEAVING A 2 I N AC; S E R V E S A S L I T E R A L
/
/ FOLLOWING I S P A R T O F WAIT LOOP, SAME SECONDARY BOOTS, OLD PRIMARY BOOT

/
START,

/
/

SDN
JMP

LOAD+l

NOW, DONE O R ERROR
S ER

SNA
JMP
TAD
LCD
TAD
AND
TAD
DCA
CON360, 3 6 0

/
/
/
/
/

/HAS DONE COME U P ; CODE S T A R T S HERE!
/NO, GO CHECK FOR READY T O T R A N S F E R

READ
UNIT
UNIT
CON360
LITRAL
RX1SAV

/ S K I P ON AN ERROR, TRY ANOTHER D E N S I T Y ETC.
/NASTY, AC-2 FOR ABOUT T O DO S I L O , 0 ON START-UP
/START-UP,
GO S E T U P U N I T , THEN READ T O S I L O
/AC ALREADY 2 , P U T I N U N I T , D E N S I T Y
/TO EMPTY THE S I L O
/ S E T UP LOC 6 0 FOR OLD SECONDARY BOOT
/ K E E P I N G ONLY D E N S I T Y B I T
/ADDING I N 7 0 0 4 , BECAUSE T H A T ' S WHAT S Y S WANTS
/OLD SECONDARY BOOT MOVES I T T O HANDLER
/ L I T E R A L ; EXECUTES I N L I N E A S A NO-OP
/ F A L L S THRU T O NEXT PAGE O F L I S T I N G

FOLLOWING CODE SAME A S OLD PRIMARY BOOT
J MS
DC A
ISZ
JMP

LOAD
2

/GRAB NEXT I T E M FROM S I L O
/ T R A D I T I O N ; SECONDARY BOOT S T A R T S LOADING A T 2 1
/INCREMENT LOAD ADDRESS
/GO BACK FOR ANOTHER

/
/
/

SECONDARY BOOT LOADS OVER PRIMARY BOOT U N I T LOCATION 4 7 IS LOADED,
THEN CONTROL P A S S E S T O SECONDARY BOOT

RX02 BOOTSTRAP PROGRAM
00053
00054
00055
00056
00057

0000
6753
5033
6752
5453

LOAD,

/
/
/
/
/
00060
00061

0420
0020

0
STR
JMP
XDR
JMP I

LOAD

6 0 GOES TO OLD SECONDARY BOOT
6 1 HAS DENSITY AND UNIT THAT BOOTED SUCCESSFULLY

CON420,
RXlSAV, 420
20
UNIT,

START

/SUBROUTINE TO GIVE AND TAKE DATA FROM CONTROLLER
/ I S HE READY TO TALK TO US?
/NO, I S HE PERHAPS DONE WITH S I L O , OR I N ERROR?
/YES, DATA I N OR 0 U T ; I F DATA TO CONTROLLER, AC UNCHANGED
/NO MAGIC, JUST EXIT FROM SUBROUTINE

/USE I T TO HOLD 420 LITERAL TO START OUT
/UN1~'20+7004 TO GO TO SYS HANDLER
/ < D E N S I T Y " ~ O ~ > + < U N I T " ~THAT
O > BOOTED OK

APPENDIX B

RL01 BOOTSTRAP PROGRAM

AC0001=CLA
ACO003=CLA
AC0006=CLA
AC2000=CLA
BOOT,

IAC
C L L CML I A C RAL
C L L CML I A C R T L
C L L CML RTR

RLDC
AC0001
J M S 10
TAD

JMS 10
RRS I
BSW
RTR
RRS I
AND C 3 7 7
RAL
RLCA

/CLEAR
/CLEAR

CONTROLLER R E G I S T E R S
DRIVE REGISTERS

/ A C = 1 0 0 4 (BYTE MODE READ HEADER
NOTE THAT THIS WORD
/FUNCTION).
/MUST BE A T LOC 0 0 0 4 !
/READ NEXT HEADER I N ORDER TO
/ F I N D OUT CURRENT C Y L I N D E R
/READ HEADER BYTE # 1
/GET L S B O F C Y L I N D E R
/READ HEADER BYTE # 2

/CONSTRUCT C Y L I N D E R ADDRESS
/USE I T A S D I F F E R E N C E WORD T O
/SEEK T O CYLINDER 0 , SURFACE 0
/AC=SEEK FUNCTION
/SEEK T O TRACK 0
/AC=SECTOR 2 0 ( 0 ~ 8BLOCK 0 )
/LOAD SECTOR ADDRESS

AC0003
J M S 10
AC2000
RLSA
TAD C 7 6 0 0
/LOAD WORD COUNT FOR 1 PAGE
RLWC
AC0006
/READ FUNCTION
J M S 10
/READ SECONDARY BOOTSTRAP
/READING I N SECONDARY BOOTSTRAP PREVENTS "10" FROM
/RETURNING. CONTROL C O N T I N U E S I N SECONDARY BOOTSTRAP.

10,

0
RLCB
RLSD

J M P .-I.
RLSE
J M P I 10
J M P BOOT

/EXECUTE THE FUNCTION
/WAIT U N T I L DONE
/NOTE: THIS WORD AND N E X T
/ONE MUST BE LOCATED HERE
/ I N ORDER TO MATCH UP WITH
/SIMILAR INSTRUCTIONS CON/TAINED I N THE SECONDARY
/BOOTSTRAP.
/NO ERROR; RETURN
/ERROR: TRY AGAIN

INDEX

ABSLDR, 15

Bad-block mapping,
on RL01, 22
BASIC,
patch for BRTS, 4
BATCH,
use with RL01, 23
BOOT program, 5, 32
Bootstraps,
for RL01, 6
for RX02, 5
BUILD program, 5, 37

CDF instruction,
use with extended memory, 13
CIF instruction,
use with extended memory, 13
Command registers,
RL01, 26, 27
Core Control Block,
altering with SAVECB, 17
use with FUTIL, 5

Data space,
RL01, 28
Device names ,
RL01, 23
RX02, 18
Disk format,
RLO1, 25, 33
Distribution media, 3

Extended mode register, 14

FIELD pseudo-operator,
use with extended memory, 13
FORTRAN,
patch for FRTS, 4
FUTIL, 5

Hardware disk address,
RL01, 28

Instruction set,
RL01, 27
IOT instructions,
use with KT8A, 4

Loading instructions,
RLO1, 31
LXM instruction, 14

Memory address register,
RLO1, 25
MEMORY command, 12
Monitor head,
moving with PIP, 4

ODT, use with extended memory,
9-11

PALS,
use with extended memory,
12-15
Patches,
for BRTS, 4
for FRTS, 4
PIP, 4

RESORC, 3
Restrictions on extended memory,
for ABSLDR, 15
for MEMORY, 12
for Monitor, 8
for START, 9
RL8A controller format, 25-27
RLFRMT, 33
messages, 34-37
RL01 disk, 22-37
bad-block mapping, 22
bootstrapping, 6, 32
building a system on, 37
command registers, 26-27
data space, 28

RL01 disk (Cont. ) ,
devices A, B, and C, 23
disk format, 25, 33
handlers, 30
hardware disk addresses, 28
instruction set, 27
loading instructions, 31
memory address register, 25
RL8A controller, 25-27
RLFRMT, 33
ROM bootstrap, 32
sector address register, 26
word-count register, 26
ROM bootstrap,
for RL01, 32
RX01 diskette,
compatibility with RX02, 19
formatting with RXCOPY, 22
interleave scheme, 20

RX02 diskette,
device names, 18
formatting with RXCOPY, 19, 22
interleave scheme for dualdensity, 21
SAVE command,
use with extended memory, 8-9
SAVECB program, 17
Sector address register, 26
START command,
restrictions on use, 9

VXAO device, 16
Word-count register, 26

OS/8
Device Extensions
User s Guide
AA-D3 19A-TA
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