Utilities

ACT (Amend Configuration Table)

Step	Prompt	Action
`1`	`PASSWORD`	Enter Systems Password.
`2`	`DISC NO`	Either enter System Dic Number (range `001` to `377` octal), or ESCAPE to `PROGRAM?`
`3`		The Configuration Table held at Sector `000042` on the stated disc is read into core. Amendments made to the table by the following instructions have no effect on the existing configuration until the system is re-bootstrapped off the relevant disc.
`4`	`AMEND DEVICE TYPES?`	Either ACCEPT to go to step 5, or REJECT to go to step 8.
`5`	`TASK n IS xxxx?`	where n is the six-digit octal Task Number and xxxx is the four-character device identifier currently allocated to the task. Either ACCEPT to leave the device type unchanged, or enter new device identifier (see below), or enter `F` if Task n does not exist (end of list – program goes to step 7). Valid device identifiers are: `ANK` Alpha-Numeric Keyboard (8 or 16 character display). `V16` 16-line VDU (also valid for 8-line VDU). `V24` 24-line VDU. `DRI` DRI Printer. `C400` CDC 400 lpm Printer. `BCL` BCL Serial Printer. `CENT` Centronics Printer. `EMU` VDU as emulator for a printer. All required I/O Stations must be entered before Printers. The first VDU input is assigned device codes `50/40`, the next `51/41`, etc. Where both 16- and 24-line VDUs are present, the order of input will be determined by their device codes.
`6`		Program returns to step 5 for the next task, until code `F` is encountered.
`7`		The amended table is written back to disc.
`8`	`AMEND TASK DATA?`	Either ACCEPT to go to step 9, or REJECT to skip to step 13.
`9`	`TASK n BASE pp/ccss?`	Either ACCEPT to leave core partition unchanged, or enter new Absolute Address of task’s Core Partition.
`10`	If task is an I/O Station: `COMMANDS PRINTER x?`	Either ACCEPT to leave command printer unchanged, or enter Printer Code (one character `A`, `B`, ...) or enter `N` if station is not allowed to command a printer. At a one printer installation, the printer code should always be `A`.
`10`	If task is a Printer: `START QUEUE n?`	Either ACCEPT to leave start-up queue number unchanged, or enter new start-up queue number (range `0` to max queue number). This is the queue the printer will go to whenever the system is re-bootstrapped.
`11`		Program returns to step 9 for the next task, until the last task has been processed.
`12`		The amended table is written back to disc.
`13`	`AMEND PASSWORDS?`	Either ACCEPT to go to step 14, or REJECT to go to step 17.
`14`	`PASSWORD n?`	Either ACCEPT to leave Password n unchanged, or enter new password (max nine characters). The new password does not appear on the screen.
`15`		Program goes to step 14 for the next password, until all four passwords have beedn processed.
`16`		The amended table is written back to disc.
`17`	`START FILE TABLE n?`	Either ACCEPT to leave start-up file table unchanged, or enter new start-up file table number (range `0`-`3`).

BOOT (Bootstrap Utility)

Step	Prompt	Action
	`STOW CONTROL?`	LOS Bulletin No 7 (February 1978): Either ACCEPT to write the System Control Record to disc, or REJECT to proceed without writing the System Control Record. The usual practice is to ACCEPT, but this option is provided to avoid complications (e.g. if the required disc is not on-line).
`1`	`PASSWORD`	Enter Password 1.
`2`	`MASK`	Either enter LOS Switch Register Mask: `0` Restart `400` Recover from Security `1400` Recover from Security after scratching Unit 70 Fixed Disc `3400` Recover from Security Security after scratching Unit 70 and Unit 71 Fixed Disc or enter MK1 “TCRD” Address: `0` Standard (8K) Package “HOST” or ESCAPE to `PROGRAM?`
`3`	`SOURCE DISC`	Either enter LOS Source Disc Number, or enter `5` if MK1 system is to be Bootstrapped, or ESCAPE to `PROGRAM?`. The Source Disc must be loaded onto Unit 70.
`4`		The bootstrap procedure will be carried out when the Source Disc is on-line.

CALC (Octal Calculator)

Step	Prompt	Action
`1`		Station displays column headings `---OCTAL--- DECIMAL`
`2`		The calculator’s accumulator is cleared.
`3`	`+DECIMAL`	Either enter Decimal Integer (+ or -), or ESCAPE to go to step 1 to clear the accumulator (returns to `PROGRAM?` if the accumulator is already clear).
`4`		Program displays, on the same line, the double-word octal equivalent of the Integer input.
`5`		The integer input is added to the accumulator and the value of the accumulator is displayed, on the next line, in double-word octal and in Decimal.
`6`		Program goes to step 3.

CDL (Check Digit List)

Produces a printout of numbers with their associated check “digits”.

Step	Prompt	Action
`1`		Station displays `PRINT Q n` where n is a Plain Paper Queue.
`2`	`FIRST NO`	Either enter Number at which the print-out is to start, or ESCAPE to `PROGRAM?`.
`3`	`LAST NO`	Enter Number at which printout is to end.
`4`		Program posts the printout to the indicated Print Queue and goes to step 2 for the next range.

COPY (Copy Discs)

This utility will copy any number of sectors from any part of one disc onto any part of another or the same disc (unless the receiving sectors are “protected”)

The target area is re-read and a software “hash-check” is carried out.

If the source and target areas overlap, it should be noted that the copying is carried out 8 sectors at a time, using a 1K-core buffer.

Step	Prompt	Action
`1`	`PASSWORD`	Enter Systems Password. Bulletin No 5 (February 1978): this utility is now inhibited rather than password protected.
`2`	`SECTORS (DECIMAL)`	Either enter the number of sectors to be copied, or ACCEPT, if same number of sectors as last time (preset `12992` on entry), or enter `P` if target area is protected (Protection Override) (program returns to step 2), or enter `OS` to copy Operating System (program omits steps 4 and 6), or enter `CT` to copy Configuration Table (program omits steps 4 and 6), or ESCAPE to `PROGRAM?`
`3`	`SOURCE DISC`	Enter Source disc number in Octal.
`4`	`START SECTOR (OCTAL)`	Enter first sector of source disc to be copied.
`5`	`TARGET DISC`	Enter Target disc number in Octal.
`6`	`START SECTOR (OCTAL)`	Enter first sector of target disc to receive copy.
`7`	`PROCESS?`	Either ACCEPT to go to step 8, or REJECT to return to step 2.
`8`		Station will BEEP on completion of the copy, and go to step 2.

DATE (Advance System Date)

Step	Prompt	Action
`1`	`DD MMM YY ddd?`	Either ACCEPT to set the System Date equal to the displayed date (program goes to `PROGRAM?`), or REJECT to return to step 1 (program displays the following day’s date), or ESCAPE to `PROGRAM?`

DAY (Day of Week)

Step	Prompt	Action
`1`	`DATE`	Either enter Date, in the format “`d m y`” of three numberic fields separated by a space (range `1 1 10` to `31 12 99`), or ESCAPE to `PROGRAM?`
`2`		Program displays Day of Week (e.g. `TUE`) for the given date in the twentieth century.
`3`		Program goes to step 1 for the next date.

DLU (Disc Labeling Utility)

Step	Prompt	Action
`1`	`PASSWORD`	Enter Systems Password.
`2`	`DEVICE 000070?`	Either ACCEPT if indicated device holds the disc to be labelled, or enter Device Identifier: `B17` `0` if Exchangeable Cartridge, `1` if Fixed Cartridge `B16:B15` Drive Code (usually `0`) `B14:B7` `0` `B6:B1` Device Code (usually `70` or `71`) or ESCAPE to `PROGRAM?`
`3`	`DISC N0`	Either enter Disc No in Octal (range `001` to `377`), or ESCAPE to step 2.
`4`	`SECURITY?`	Either ACCEPT if this is a Security Disc, or REJECT if this is a Master Disc.
`5`		Program will label the disc on the indicated device and go to step 3. A Security Disc will be marked “All sectors protected”, a Master Disc will be marked protected up to sector `000206` octal inclusive.

Cautions

There must be no disc Read/Write activity elsewhere in the system, the disc must be on-line and ready, and the Disc Number must be unique in the system before proceeding to step 5.
The Disc Number should be marked on the cartridge in an indelible manner.
The cartridge should NEVER be re-labelled unless the data it holds is no longer required.
A Security Disc must not be re-labelled, and must not be renumbered, as a master disc. Disregard of this rule will place the installation’s data at dire risk.

Disc Labels

Each disc is identified to the operating system by Disc Number. For programming convenience the number is always given -in Octal, range 0 to 377.

The disc number is held in the first word of sector 40 (octal) of the disc, and this sector is therefore called the Disc Label. The second word of the label contains the number of the first “unprotected” sector on the disc (protection is a software feature designed to intercept any inadvertent write onto “read only” areas of the disc: LOS provides only one such area per disc).

RECOMMENDED NUMBERING CONVENTIONS

Range	Usage
`000` to `007`	Reserved. Note that because MK I package discs hold the “TCRD” in Sector `40₈`, a MK I package disc will acquire disc number `005` (with all sectors protected).
`010` to `277`	The 1^st and 2^nd digits identify the “application” of this disc, the 3^rd digit identifies the “type” of the disc as follows: `0` Master Disc. `1` “Daily” Security Copy 1 of the Master Disc. `2` “Daily” Security Copy 2 of the Master Disc. `6` “Special” Security Copy of the Master Disc `7` Working Version of Master Disc existing on a Fixed Drive.
`300` to `377`	Reserved for systems purposes (temporary fixed disc labels, etc.).

LOS Bulletin No 30 (August 1978)
DSnn (Disc Security)
A new version of the disc security overlay, Module 006 is now available. A number of improvements have been made:
The module is installation independent. The relevant-parameters (disc numbers etc.) appropriate to the installation are placed in System Module 11.
Up to seven security cartridges may participate in the “daily” rotation for each Master cartridge.
The “daily” rotation of each Master cartridge is independent of all other rotations. It is controlled by a 3-bit (1 octal digit) field in the System Control Record. One word (usually 0/0400) in the System Control Record may hold up to five such sequence control fields.
The facility is provided to “skip” a security. This is useful after a recovery, because at the next security the system asks for the latest copy discs rather than the oldest.
To Skip a Security
Enter the security program as usual, but before typing the Password check that the security cartridges to be skipped are not online.
When the message TASK n AWAITS DISC x occurs, enter program R at another station and restart task n at the default address (ACCEPT).
To Abandon a Security
Re-bootstrap.
Disc Security Utility
A “daily” disc security program must be provided at an installation for the purpose of copying each Master cartridge onto Security cartridges (at least two securities, used in rotation, for each Master cartridge).
The standard disc security utility, described below, is specifically designed for one drive installations (where the exchangeable master cannot be secured without first securing, and finally recovering, the fixed master).
The utility is called from a user written program placed in System Module 11:
JSBR IZ 1670 FETCH AND LINK MODULE 006 P1 = 002002 P2 = 0/0206 Module Number 006 P3 = Byte Address of Title P4 = Byte Address of Password = 0/1300 usually P5 = Address of Control Word, Phase 1 Control Block P6 = Address of Control Word, Phase 2 Control Block
Notes:
The program runs at an I/0 station. On completion it returns to the PROGRAM? prompt. A suitable name should be placed in the “Input” Directory. Standard names:
DS70
Daily Security, Unit 70
SS70
Special Security, Unit 70
The title (P3) appears on the I/0 station display, preceded by SECURITY.
The password will normally be Password 1; i.e. P4 = 0/1300.
Phase 1 is a direct copy: Master onto Security (both cartridges online together). Phase 2 is an indirect copy: Master via “fixed” onto security. The “fixed” cartridge is the Phase 1 Master (which is automatically recovered by a third phase).
Phase 2 is required only where direct copying is not possible. If there is no Phase 2, P6 should be set zero. If there is a Phase 2, the operator has the option to carry out Phase 1 only.
Control Block
Each phase’s Control Block is n+2 words long, where n is the number of copy discs (to be used in rotation) associated with the relevant Master disc:
CONTROL WORD MASTER DISC NUMBER COPY 1 DISC NUMBER COPY 2 DISC NUMBER ... COPY n DISC NUMBER
Control Word
B17 0
B16:B13 Cartridge Type Code:
1
D400
2
D800
2
D818
3
D1600
B12:B10 Number of copy discs. If this field is zero, one copy disc is assumed.
B9:B1 Sequence field code. Not required (i.e. zero) if there is only one copy disc. Where more than one copy disc is to be used in rotation, this field defines the octal digit (3 bits) within the System Control Record which holds the current sequence number as follows:
B9:B4
Word offset of Sequence Field from beginning of System Control Record. Thus if the Sequence Field is at 0/0400, B9:B4 are zero.
B3:B1
Digit number within the word, numbered from the right, range 1 to 5. The digit itself, within the System Control Record, should be pre-set zero.

FLAG (Switch Program Inhibit Flags)

Step	Prompt	Action
`1`	`PASSWORD`	Enter Password 1.
`2`		Program displays a list of program class numbers (one per line). Alongside each number is the class title (e.g. Class 1 = `PROGRAMMERS' UTILITIES`) and, if all users are currently prevented from entering programs of that class, the text `*INHIBITED`.
`3`	`SWITCH NO`	Either enter Class Number where Inhibit Flag is to be reversed, or ESCAPE to `PROGRAM?`
`4`		The indicated Inhibit Flag is reversed, and the program goes to step 3 for the next class number, if any.

LIST (Module/Core Dump Print Program)

Step	Prompt	Action
`1`		Program displays `PRINT Q n` where n is a Plain Paper Queue.
`2`	`MODULE`	Either enter Module number (Octal) and ACCEPT. go to step 5, or ACCEPT only to go to step 3, or ESCAPE to `PROGRAM?`
`3`	`CORE FROM`	Enter start core address (Octal).
`4`	`TO`	Enter end core address (Octal).
`5`	`TITLE`	Either enter up to 33 characters, or ESCAPE to step 2.
`6`		Program posts the request to the print queue and goes to step 2 for the next request.

MOVE (Move Overlay Modules)

Step	Prompt	Action
`1`	`PASSWORD`	Enter Systems Password. LOS Bulletin No 5 (February 1978): this utility is now inhibited rather than password protected.
`2`	`TRANSFER?`	Either ACCEPT to go to step 3, or REJECT to go to step 8, or ESCAPE to `PROGRAM?`
`3`	`SOURCE FILE TABLE`	Either enter Source File Table Number (range 0:3), or ACCEPT.
`4`	`SOURCE MODULE`	Either enter Source Module Number (in Octal), or ESCAPE to `PROGRAM?`
`5`	`TARGET MODULE`	Enter Target Module Number (in Octal). The Target Library is that currently assigned to the issuing station by the `F` command.
`5a`	`n SECTORS?` where `n` is the number of sectors in the Source Module	Added by LOS Bulletin No 12 (April 1978): Either ACCEPT if target is to be the same size, or enter required number of sectors in Target Module (in decimal), or ESCAPE to step 4. If the target is smaller than the source, the high-order sectors of the source will be omitted. There is no provision for amending the core loading point. To amend the size of an existing module, set TARGET=SOURCE Module Number. It is always advisable to ensure there are sufficient spare sectors in the target library (the full number of sectors are required, even if the target already exists).
`6`		The Source Module will be copied to the Target Module, and the Target Library Index appropriately updated. The Target Module will replace any previous module with the same module number in the Target Library.
`7`		Program displays `MOVED` and goes to step 4 for the next transfer.
`8`	`COMPRESS?`	Either ACCEPT to go to step 9, or REJECT to return to step 2. Library Compression eliminates space within the Library which has become wasted due to the deletion of modules or due to the transfer of new versions from other libraries.
`9`		Program posts the Compression request to the deletions print queue and returns to `PROGRAM?` LOS Bulletin No 12 (April 1978) changed the posting to the issuing station’s plain paper queue. When the posting is processed by the printer program, the program will seize as workspace an area of the spool file equal in size to the Overlay Library. The message `OVERLAY LIBRARY COMPRESSION IN PROGRESS` is flashed to all stations (if there is insufficient free spool space an abort message will be flashed in lieu). The library is copied module by module to the work area. The work area is then copied back over the library. Unused sectors in the overlay library are zeroed, the Sectors in Use count in the File Status Block is updated and the System Control Record is stowed. Finally the message `COMPRESSION ENDED` is flashed to all stations. No printing occurs. The Library compressed is that assigned to the issuing station by the `F` command. Do not attempt to enter a program at any I/0 station whilst compression is in progress (a Program Hash Fail halt may occur). If a system failure occurs during compression, it will be necessary to deem the library corrupted. It is therefore advisable to carry out a security copy operation beforehand.

OP (On-Line Program Amendment)

Program OP described below is available at all I/0 stations. It provides facilities to transfer Overlay Modules between disc and the station’s core partition, and to interrogate and amend any part of core.

Interrogation and amendment may be performed in Octal or Literal (ASCII) mode. When in Octal Mode the program attempts to decode machine instructions.

Do not amend the same Overlay Module simultaneously in two separate core partitions. Do not leave the station unattended whilst in program OP.

Step	Prompt	Action
`1`
`2`		Numeric data entered below will be interpreted as OCTAL. The `/` character is treated as numeric and indicates bit input (`0` or `1` must follow): e.g. `5/0000` is interpreted as `012000`. The `.` character is treated as numeric and adds bit-16 to the input; e.g. `5/0000.` is interpreted as `112000` (allows Byte Addresses to be input).
`3`		Any non-numeric character terminates an octal field. The ACCEPT key must not be used as a terminator. The REJECT key is used to cancel an error, and the ESCAPE key will always lead back to `PROGRAM?` selection.
`4`		The station cannot obtain Command Mode within this program.
`5`	`OP?`	Either enter `nR` to read Overlay Module n from disc (go to step 6), or enter `nW` to write Overlay Module n back to disc (return to step 5) (ERROR if Module was not first read from disc), or enter `xA` to set MEMORY ADDRESS to address x (go to step 7), or enter `xI` to set MEMORY ADDRESS to the address contained in core location x (go to step 7), or enter `x[space]` to display ASCII at address x (return to 5) (display ends on encountering a NUL byte), or ESCAPE to `PROGRAM?`
`6`		The Overlay Module is read into the station’s core partition at its proper offset. MEMORY ADDRESS is set to the absolute address of the first word of the Module within the partition.
`7`	`a x d` where: `a` is a six digit octal number, the value of MEMORY ADDRESS. `x` is a six digit octal number, the CURRENT contents, in core, at the MEMORY ADDRESS. `d` is a 12 character string, the machine instruction DECODE of x.	Either RESET to re-examine `x` and `d` at `a` (return to step 7), or enter `n[RIGHT ARROW]` to increment a by n words (n = 1 by default) (return to step 7) (each word is displayed in the format `a x d`) or enter `n[LEFT ARROW]` to decrement a by n words (n = 1 by default) (return to step 7) (each word is displayed in the format `a x d`) or enter `yO` to set MEMORY ADDRESS to the value (y + partition base), i.e. to the offset y within the station partition (return to step 7) or enter `yA` to set MEMORY ADDRESS to the Absolute value y (return to step 7) or enter `yI` to set MEMORY ADDRESS to the value contained in Absolute Core Location y (return to step 7), or enter `y[SPACE BAR]` to display ASCII at absolute address y (return to step 7) (display ends on encountering a NUL byte) (y = a by default), or enter `l` and ACCEPT to load l into a (go to step 8) 16 line VDU: Do not accept; use `[DOWN ARROW]` or `[GS]`, or enter `l` and REJECT to load l with bit-17 set into a (go to step 8) (allows Offset addresses to be input) 16 line VDU: use `[FS]`, or enter `y` to switch to Literal (ASCII) input (go to step 10) (y=a by default) or ESCAPE to `OP?`
`8`		Program displays `x d` the new values of CURRENT and DECODE at the MEMORY ADDRESS.
`9`		MEMORY ADDRESS is incremented by one and the program returns to step 7.
`10`	`LIT:`	Enter ASCII characters and ESCAPE to step 7. All characters entered are loaded (2 characters per word) except the ESCAPE character. Lower case input is converted to upper case. MEMORY ADDRESS is incremented by one after every second character. If an odd number of characters is entered the second byte of the last word is left unaltered. Back-spacing does not correct a typing error, but simply loads ASCII `BS` into the current byte.

PLM (Program Library Maintenance)

Step	Prompt	Action
`1`
`2`	`AMEND DIRECTORY?`	Either ACCEPT to go to step 3, or REJECT to go to step 10, or ESCAPE to `PROGRAM?`. There are two seperate directories, one for Input programs and one for Print programs.
`3`	`"INPUT"?`	Either ACCEPT to amend the I/0 Station directory, or REJECT to amend the Print directory.
`4`	`NAME`	Enter up to 4 characters. A short name will be automatically space-filled to four characters.
`5`		If the name is not already in the directory Station will BELL and display `NEW NAME`.
`6`	`MODULE n?` where `n` is module number in octal	Either ACCEPT to leave `n` unchanged, or enter `x` where `x` is the required module number in Octal, or enter `0` to delete the name from the directory and go to step 9.
`7`	`ENTRY x?` where `x` is a core location (absolute or offset)	Either ACCEPT to leave the logical entry point `x` unchanged, or enter `y` where `y` is the required entry point (absolute or offset).
`8`		The directory entry will be added or amended as appropriate, and the program goes to step 2 for the next operation.
`9`		Station will BELL and display `x DELETED` where `x` is the program name, Program goes to step 2 for the next operation.
`10`	`NEW OVERLAY`	Either ACCEPT to go to step 11 to add a new overlay module to the library, or REJECT to go to step 2.
`11`	`MODULE`	Enter module number in Octal
`12`		If the module number is already in use, station will bell and display `LOADED` and will return to step 11.
`13`	`SECTORS (DECIMAL)`	Enter number of sectors required (in decimal) (Range 1-13)
`14`	`START LOC'N`	Enter Core address (absolute or offset).
`15`	`AUTO-RESOLVE?`	Either ACCEPT if the overlay begins with a block of offset addresses, or REJECT otherwise. LOS Bulletin No. 3 (January 1978): This prompt has been removed. Henceforth, offset address resolution will be carried out when, and only when, overlay modules are fetched into core by program name.
`16`		Disc space is reserved for the new overlay module and its particulars are added to the index. Program goes to step 2 for the next operation.

PMAP (Print Program Map)

Produces a print-out, in Overlay Module Number order, giving details of all overlay modules.

Step	Prompt	Action
`1`		Program displays `PRINT Q n` where n is a Plain Paper Queue.
`2`	`PROCESS?`	Either ACCEPT to print the entire map (go to step 4), or enter first module number in octal, or REJECT to return to `PROGRAM?`
`3`	`LAST`	Either ACCEPT if only one module is to be printed, or enter last module number in octal.
`4`		Program posts to print queue and returns to `PROGRAM?`

R (Restart Task)

This program may be used after a TASK HALTED message has been issued by the system; it enables programmers to restart programs under test at any point.

Step	Prompt	Action
`1`		Program may display `INHIBITED!` and go to `PROGRAM?` Enter program `FLAG` and switch the programming utilities flag.
`2`	`TASK NO`	Enter Task Number (in Octal) of the task to be restarted.
`3`	`ADDRESS`	Either enter Core Address (absolute or offset) at which the task is to be restarted, or ACCEPT to restart at the beginning of the task control program.
`4`		If the task is indeed halted, it will now restart at the indicated address and program returns to `PROGRAM?`

READ (Disc Read Utility)

Step	Prompt	Action
`1`	`PASSWORD`	Enter Systems Password.
`2`	`DISC NO.`	Either enter Disc Number holding sector to be read, or ACCEPT to go to step 8 (Read Record).
`3`	`SECTOR`	Either enter Absolute Sector Number in Octal, or enter `n` and REJECT to go to step 6 (Overwrite), or ESCAPE to `PROGRAM?`
`4`		Program displays the core buffer address into which the sector has been read, followed by the 128 words of the buffer in 6-digit octal (8 words per line).
`5`		Program goes to step 3.
`6`	`OVERWRITE?`	ACCEPT to write the core buffer to sector `n`. If `n` = 0, the buffer will be written back to the same sector as was most recently read or written.
`7`		Program goes to step 4.
`8`	`FILE ID`	Either enter 2-digit Octal File Identifier, or ESCAPE to `PROGRAM?`
`9`	`TEST?`	Either ACCEPT if the "TEST" option is to be applied on fetching the record at step 10, or REJECT otherwise.
`10`	`KEY`	Either enter Record Key in the format applicable to the file, or ESCAPE to step 8.
`11`		Program displays the Core Address of the record within its transfer buffer, followed by each word of the record in 6-digit octal (8 words per line).
`12`		Program goes to step 8.

RP (Reprint Utility) (released September 1978)

Step	Prompt	Action
`1`	If there is more than one printer: `PRINTER A?`	Either enter Printer Identification letter, or ESCAPE to `PROGRAM?`
`2`		Progam displays `PRINT Q n` where `n` is the Reprint Queue of the selected printer. Each printer has its own reprint queue; re-printable work processed by the printer is placed into its reprint queue regardless of its queue of origin.
`3`	`SERIAL NO`	Either enter Serial Number of the document to be reprinted, or ACCEPT if this is an enquiry only, or ESCAPE to `PROGRAM?` If more than one document is to be reprinted, enter the oldest serial number.
`4`		The program searches the reprint queue for a document with the specified serial number. As the search proceeds, the program displays the four character program name and the serial number of each item in the queue.
`5`	If the serial number is found: `REPRINT?`	Either ACCEPT to request a reprint and go to step 6, or REJECT to go to step 6, or ESCAPE to `PROGRAM?`
`6`		The program displays the next item in the queue and goes to step 5. When the end of the queue is reached, program goes to `PROGRAM?`.

If ACCEPT was pressed at step 5 for any item, the utility places a marker at the current end of the reprint queue. A printer commanded to process the reprint queue examines each item in the queue in chronological order. Items with reprints pending will not only be reprinted but will be re-posted to the end of the re-printing printer’s reprint queue in case a further reprint is required. Items without reprints pending will be dropped and it is now too late to request a reprint. When the marker placed by RP is encountered in the queue, the printer switches itself onto print queue 0 and becomes IDLE, thus allowing the operator the opportunity to request re-re-prints. There may be more than one such marker in the queue, if RP was used more than once.

Important

Items become available for reprinting. (i.e. are posted to the reprint queue) immediately printing of the original begins. Thus, if the printer breaks down during the printing of the original it is possible to obtain the reprint (if another printer is available to print it) before the original. However, the file updates that would have been done whilst printing the original will not yet have been completed; indeed they will only be carried out if the original printer can be repaired without having to re-bootstrap the operating system.

S (Send Message)

Step	Prompt	Action
`1`	`TASK`	Either enter Task Number (in Octal) of destination, or ACCEPT if to be sent to all Stations, or ESCAPE to `PROGRAM?`
`2`	`TEXT`	Enter message text.
`3`		The text will be flashed (with BEL tone) to the destination station(s) and program goes to step 1.

SE (System Enquiry)

I/O stations precede printers in the display; printer task numbers are followed by the printer identification letter. The name of the program currently being run appears to the right of the task number.
The POST-Q column gives the number of the print queue into which the task is posting print requests.
BASE is the base address of the main core partition assigned to the task.
U-Q against I/O stations gives the plain paper print queue currently assigned by the U command; against printers gives the print queue from which the printer is unspooling work.
LOADED applies only to printers and gives the name of the program now loaded in the task partition.
F-TABLE gives the core address of the File Table assigned to the task.
PHASE and AT give the reason, and core address at which, the task relinquished CPU control to the task scheduler (the issuing task will have CPU control at the time of display).

Standard Phases

GET 04/1430: PROGRAM? prompt
GET 13/0350: COMMAND? prompt
GET 03/0706: PASSWORD prompt
PAUSE 04/1523: Print Program idle
PAUSE 04/0207: Print Program awaiting free Buffer
PAUSE 04/0345: Print Program suspended by operator
PAUSE 03/1133: Task Halted by Program
PAUSE 13/0355: I/O Station queued for Command Handler

ZERO (Zeroise Sectors)

Step	Prompt	Action
`1`	`PASSWORD`	Enter Systems Password. LOS Bulletin No 5 (February 1978): this utility is now inhibited rather than password protected.
`2`	`DISC NO`	Enter Disc Number (octal).
`3`	`START SECTOR (OCTAL)`	Enter Start Sector Number (octal).
`4`	`SECTORS (DECIMAL)`	Enter Number of Sectors to be cleared, in decimal.
`5`	`PROCESS?`	Either ACCEPT to continue, or REJECT to go to step 2.
`6`		Station will bell and return to `PROGRAM?` on completion.

`B17`	`0`
`B16:B13`	Cartridge Type Code: `1` D400 `2` D800 `2` D818 `3` D1600
`B12:B10`	Number of copy discs. If this field is zero, one copy disc is assumed.
`B9:B1`	Sequence field code. Not required (i.e. zero) if there is only one copy disc. Where more than one copy disc is to be used in rotation, this field defines the octal digit (3 bits) within the System Control Record which holds the current sequence number as follows: `B9:B4` Word offset of Sequence Field from beginning of System Control Record. Thus if the Sequence Field is at `0/0400`, `B9:B4` are zero. `B3:B1` Digit number within the word, numbered from the right, range `1` to `5`. The digit itself, within the System Control Record, should be pre-set zero.