Function
Changes the state of a multiplexer, uniplexer or communications processor from being available for system use to being available for use on-line by object program only, or vice versa.
Format
Format 1 indicates to GEORGE that the device is available for system use and format 2 switches off system use, making the device available for connection to an object program. The peripheral description is the operator's number of a multiplexer, uniplexer or communications processor.
NEWSPEC and LIMBO may be abbreviated to NS and LI respectively. NEWSPEC, PM and LIMBO are optional, and in format 2 PM and LIMBO may appear in either order.
NEWSPEC and PM are applicable only if peripheral description refers to a communications processor but if the communications processor is a virtual 7900 communications processor, NEWSPEC is not applicable and will be ignored if present. LIMBO is applicable to any type of device covered by MOP.
NEWSPEC indicates that the configuration specified to the communications processor has been altered, and causes GEORGE to update the IDF to take account of this.
PM indictates that no further attempt is to be made to output to the communications processor, thereby allowing a clean postmortem to be taken from it.
LIMBO indicates that any active MOP jobs should be sent into limbo rather than being abandoned. These jobs may than be reCONNECTed when the MOP service is resumed.
Forbidden contexts
NOT OPERATOR, REMOTE
Execution
A check is made to ensure that the number given is a multiplexer, uniplexer or communications processor.
Format 1 (MOP ON)
If the specified device is marked free, GEORGE will allocate the device to GEORGE itself and go into the starting up sequence. If the specified device is not free, that is, it is on-line to an object program, then the MOP command is not obeyed.
If the NEWSPEC parameter is not included, and the IDF does not already
contain information on the identifiers on the communications processor,
GEORGE simulates the presence of NEWSPEC and outputs the messages:
NO CONFIGURATION IS DEFINED FOR UNIT n
IN THE INSTALLATION DESCRIPTION FILE
UNIT n: CONFIGURATION UPDATE BEING
TAKEN
If a configuration report is obtained successfully as a result of
simulating a NEWSPEC parameter, the operator is informed with the
message
UNIT n: UPDATE SUCCESSFUL
and the MOP ON process continues in the normal way. If the communications
processor is inoperable or, if the DCP in use does not have the
configuration report option, the operator is informed with the
messages
UNIT n: UPDATE FAILED
UNIT n: MOP ON ABANDONED
Format 2 (MOP OFF)
If the specified device is marked allocated to GEORGE, then any terminals
being used for MOP will be closed down and any jobs running from those
terminals will be abandoned, unless the LIMBO parameter was included in
which case these jobs will be put into limbo, The message:-
JOB ABANDONED: MOP SWITCHED OFF
or
JOB IN LIMBO: MOP SWITCHED OFF
as appropriate will be sent to each affected MOP terminal. Jobs already
in limbo are not affected.
A message explaining why the jobs have been abandoned will be sent to each terminal unless the device is a communications processor and the PM parameter is present. The multiplexer or uniplexer will be left in such a state that it can subsequently be ONLINEd to an object program.
Messages during MOP ON/OFF
If the operator attempts to switch to the current state will receive the
reply:-
UNIT n IS ALREADY MOPPED ON
or
UNIT n IS ALREADY MOPPED OFF
When the MOP command has been completed the operator will be informed
with the message:-
UNIT n: MOP ON COMPLETED
or
UNIT n: MOP OFF COMPLETED
An attempt to do a further MOP command on the same device before this
message has appeared will result in either:-
MOP ON IS NOT ALLOWED ON UNIT n DUE
TO PREVIOUS INCOMPLETED MOP COMMAND
or
MOP OFF IS NOT ALLOWED ON UNIT n DUE
TO PREVIOUS INCOMPLETED MOP COMMAND
The operator should wait until he receives the message:-
MOP ON COMPLETED
or
MOP OFF COMPLETED
before re-issuing the command.
If an attempt is made to issue a MOP OFF command for a physical
multiplexer which has certain of its lines ATTACHed to a conceptual multiplexer that is
ONLINE to a job, the MOP OFF
command will not be implemented and the operator will be informed with
the message:-
MOP OFF IS NOT ALLOWED ON UNIT n DUE
TO ONLINE CONCEPTUALS
When the operator receives this message it is recommended that an IDFLISTcommand be issued and the resultant output studied to decide the best course of action. Possible actions are as follows:
Error Messages
z IS NOT A SUITABLE DEVICE
z IS NOT IN THE REQUIRED STATE