Type ASSEMBLE
Source Lines : 909
Fixes Applied : 1
Most Recent Version : Thursday, December 7, 1978
Last Fix ID : [R09681DK]

Module

       DMKVMI

Function

       TO SIMULATE A USER'S IPL I/O SEQUENCE

Attributes

       RESIDENT IN A PAGE OF THE USER'S VIRTUAL MEMORY, DMKVMI RUNS
       IN THE VIRTUAL MACHINE UNDER CONTROL OF THE USER'S VIRTUAL
       PSW AND IN PROBLEM STATE.  SIO INSTRUCTIONS ISSUED BY THE
       IPL SIMULATOR ARE HANDLED EITHER BY CCW TRANSLATION OR SIMU-
       LATION BY DMKVSPEX.

Operation

       1.  SAVE REGISTERS AND ESTABLISH MODULE BASE REGISTER.
       2.  GET IPL AND CONSOLE DEVICE ADDRESSES.
       3.  SAVE USER CAW AND IPL DEVICE CLASS AND TYPE.
       4.  IF DEVICE CLASS IS DASD GOTO DISK ROUTINE.
       5.  IF DEVICE CLASS IS TAPE GOTO TAPE ROUTINE.
       6.  IF DEVICE CLASS IS EITHER UNIT RECORD INPUT OR SPECIAL
            (CTCA), GO TO READER ROUTINE.
       7.  IF DEVICE CLASS IS NONE OF THE ABOVE, GIVE MESSAGE
           'INVALID IPL DEVICE TYPE' AND LOAD DISABLED WAIT STATE.

       (OPERATION OF THE DISK, TAPE, AND READER ROUTINES BELOW)

       7.  EXECUTE THE LAST CCW.
       8.  IF THE PSW AT VIRTUAL X'0' HAS THE EXTENDED BIT ON PLACE
           THE IPL DEVICE ADDRESS IN VIRTUAL LOCATION X'BA';
            OTHERWISE PLACE IT IN VIRTUAL LOCATION X'2'.
       9.  RESTORE REGISTERS AND LATEST CAW.
       9A. FOR IPL STOP OPTION GET THE PSW ADDRESS FROM
       LOCATION 4 AND CONVERT TO AN ADSTOP ADDRESS.
       ISSUE CP DIAGNOSE 8 TO SET ADSTOP AT PSW LOCATION.
       10. LOAD PSW AT VIRTUAL LOCATION X'0'.

Calls to Other Routines

       NONE