From NDWiki
Jump to navigation Jump to search
@LOOK-AT <space-reference> [,<additional parameter>]

This command may be used to examine or modify memory locations and registers. <space-reference> may be

user's virtual memory space. Permitted for all users.
user's alternative 64K memory Addresses are specified relative to the 64K boundary. Permitted for all users.
an existing segment. <additional parameter> = segment number. Permitted only for users RT and SYSTEM.
common area for RT programs. Permitted only for users RT and SYSTEM.
memory of the resident part of SINTRAN III on mass storage. A modification is permanent until a a )HENT command overwrites the image. Permitted only for user SYSTEM.
resident memory (0 - 177777 octal). This includes the resident part of SINTRAN III. Permitted only for user SYSTEM. Page Tables (PT) can be accessed at the following octal addresses:
PT0: 177400 - 177477
PT1: 177500 - 177577
PT2: 177600 - 177677
PT3: 177700 - 177777
all registers on all hardware interrupt levels may be examined but only the registers on levels 2, 5, 6, 7, 8, 9 and 15 may be changed. The register is specified as an octal number indicating the level, followed by the register name. Permitted only for users RT and SYSTEM.


  1. Permission depends on the <space reference> as shown above.
  2. When the <space reference> given has been checked for legality, the message READY is typed.
  3. To examine a location, the octal address should be typed followed by a slash (/). The contents will the be printed in octal. The contents may now be changed by typing an octal value, followed by a carriage return. The value may be negative (preceded by a minus sign). If only cr is typed, the contents remain unchanged and the contents of the next location are printed.
  4. If an asterisk (*) is typed, the current address will be printed.
  5. For REGISTERS the valid names are P, X, T, A, D, L, S and B.
  6. When an illegal character is typed, a question mark is printed. Illegal characters have no effect. The command is terminated by a dot (.) or by a commercial at (@).
  7. If locations on mass storage segments are changed, the pages will be written out so that "patches" will be made permanent. Locations changed in the user's virtual memory or the resident part of the operating system are temporary. They may be altered when loading a user program or reloading the system.
  8. If <space reference> is SEGMENT or IMAGE the changes will only take place when the command is terminated correctly (i.e., no if escape is pushed).




1000/ 10 100



Location 1000 (octal) in users virtual memory is changed from 10 (octal) to 100 (octal), and 11 (octal) is the contents of location 1001 (octal).


5X/ 10 100



The X register on level 5 is changed from 10 (octal) to 100 (octal).

Related commands


@STATUS (command)


Norsk Data Document ND–60.050.06 SINTRAN III USERS GUIDE sections, 5.4 and 6.4.3

Norsk Data Document ND–60.128.01 SINTRAN III REFERENCE MANUAL (printed June 1980), pages 1-103, 1-104