Programming Interface Information: This information is NOT intended to be used as Programming Interfaces of z/VM.

#### IOCON

Prolog

Control Block Contents
IOCON DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### IOCON Prolog

     Name       : DMSIOCON
     Description: Console I/O Workarea
     DSECT      : IOCON
     Function   : To provide a workarea in low storage for the
                  first path and device entries opened for better
                  performance. Also provides a workarea for
                  linemode and XA ccws and I/O control blocks.
                  Also provides a communications area for DIAG
                  X'264' instruction. Also provides the workarea
                  for the SET CMS370AC ON/OFF command.

#### IOCON Control Block Content

#### IOCON DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      IOCON          Console I/O Workarea
    0000    0 Bitstring  112 IOCPATH        Storage for first path entry
    0070  112 Signed       4 * (0)          Device entry on fullword bndry
    0070  112 Bitstring 1120 IOCCDEV (0)    Storage for first device entr
    0070  112 Bitstring    1 * (1120)       Initialize to 0s
    04D0 1232 Bitstring  160 IOCIDAL        IDAL Buffer for XA mode
            INTERACTIVE CONSOLE COMMUNICATION CHANNEL PROGRAM FOR 370
    0570 1392 Dbl-Word     8 * (0)
    0570 1392 Bitstring    8 IOCSCCW        SENSE CCW FOR 370
    0578 1400 Bitstring    8 IOCPCCW        ASCII PROMPT CCW FOR 370
    0580 1408 Bitstring    8 IOCCCWS        READ/WRITE CCW FOR 370
    0588 1416 Bitstring    8 IOCNCCW        NO-OP CCW FOR 370
            INTERACTIVE CONSOLE COMMUNICATION CHANNEL PROGRAM FOR XA
    0590 1424 Dbl-Word     8 * (0)
    0590 1424 Bitstring    8 IOCSCCWX       SENSE CCW FOR XA
    0598 1432 Bitstring    8 IOCPCCWX       ASCII PROMPT CCW FOR XA
    05A0 1440 Bitstring    8 IOCCCWSX       READ/WRITE CCW FOR XA
    05A8 1448 Bitstring    8 IOCNCCWX       NO-OP CCW FOR XA
    05B0 1456 Signed       4 * (0)
    05B0 1456 Bitstring   12 IOCWKCSW (0)   WORK CSW/SCSW MOVED FROM IOSECT
    05B0 1456 Signed       4 IOCWKCCF       CONDITION CODES/FLAGS
    05B4 1460 Signed       4 IOCWKCCW       ADDR OF LAST CCW EXECUTED
    05B8 1464 Bitstring    1 IOCWKUST       UNIT STATUS
    05B9 1465 Bitstring    1 IOCWKCST       (SUB)CHANNEL STATUS
    05BA 1466 Signed       2 IOCWKRCT       RESIDUAL COUNT
            IRB DEFINITIONS FOR TEST SUB-CHANNEL
    05BC 1468 Signed       4 IOCIRB (0)     IRB
    05BC 1468 Bitstring   12 IOCISCSW (0)   SUB-CHANNEL STATUS WORD
    05BC 1468 Signed       4 IOCICCFL       CONDITION CODES/FLAGS
    05C0 1472 Signed       4 IOCICCW        ADDR OF LAST CCW EXECUTED
    05C4 1476 Bitstring    1 IOCIUST        UNIT STATUS
              1... ....      IOCIATTN       X'80' ATTENTION
              .1.. ....      IOCISTMD       X'40' STATUS MODIFIER
              ..1. ....      IOCICUE        X'20' CONTROL UNIT END
              ...1 ....      IOCIBUSY       X'10' BUSY
              .... 1...      IOCICHEN       X'08' CHANNEL END
              .... .1..      IOCIDVEN       X'04' DEVICE END
              .... ..1.      IOCIUNCK       X'02' UNIT CHECK
              .... ...1      IOCIUNEX       X'01' UNIT EXCEPTION
    05C5 1477 Bitstring    1 IOCISCST       SUB-CHANNEL STATUS
    05C6 1478 Signed       2 IOCIRCT        RESIDUAL COUNT
    05C8 1480 Signed       4 IOCIESW (5)    EXTENDED STATUS WORDS
    05DC 1500 Signed       4 IOCIECW (8)    EXTENDED CONTROL WORDS
            ORB DEFINITIONS FOR START SUB-CHANNEL
    05FC 1532 Signed       4 IOCORB (0)     ORB
    05FC 1532 Signed       4 IOCOINTP       INTERRUPTION PARAMETER
    0600 1536 Bitstring    1 IOCOKSR        SUB-CHN KEY, SUSPEND CONTROL FLAG
    0601 1537 Bitstring    1 IOCOFPIN       FORMAT, PREFETCH, INTERRUPT FLAGS
              1... ....      IOCOFORM       X'80' FORMAT CONTROL
              .1.. ....      IOCOPREF       X'40' PREFETCH CONTROL
    0602 1538 Bitstring    1 IOCOLPM        LOGICAL PATH MASK
    0603 1539 Bitstring    1 IOCORES        RESERVED
    0604 1540 Signed       4 IOCOCPA        CHANNEL PROGRAM ADDRESS
            GENERAL I/O WORK AREA
    0608 1544 Bitstring   16 IOCWORK (0)    GEN. PURPOSE I/O WORK AREA
    0608 1544 Bitstring    1 IOCWFLG1       FULLSCREEN CONSOLE I/O FLAGS
              1... ....      IOCWASYN       X'80' ASYNCHRONOUS INTERRUPT
              .1.. ....      IOCWCP11       X'40' VM/ESA CP 1.1 and higher
              ..1. ....      IOCWCP20       X'20' VM/ESA CP 2.0 and higher
              ...1 ....      IOCWLMQ        X'10' 1=Disc/Reco indicator for
                                            linemd
    0609 1545 Bitstring    1 IOCWAMOD       AMODE SETTING
    060A 1546 Bitstring    2 IOCWFLGS       RESERVED FLAG BYTES
    060C 1548 Bitstring   12 IOCWRES        RESERVED
    0618 1560 Bitstring    8 IOCCOMM (0)    DIAG X'264' COMMUNICATION AREA
    0618 1560 Bitstring    1 IOCCFLG1       FLAG 1 OF COMMUNICATION AREA
              1... ....      IOCCRECO       X'80' DISCONNECT/RECONNECT BIT
              .1.. ....      IOCCLMIO       X'40' FULLSCR/LINEMODE BIT
                                            (1=LINEMODE)
              ..1. ....      IOCCSHDT       X'20' 1=VM DEF DATE FORMAT IS
                                            SHORTDATE
              ...1 ....      IOCCFLDT       X'10' 1=VM DEF DATE FORMAT IS
                                            FULLDATE
              .... 1...      IOCCISDT       X'08' 1=VM DEF DATE FORMAT IS
                                            ISODATE
    0619 1561 Bitstring    7 IOCCRES        RESERVED BYTES IN COMM. AREA
    0620 1568 Signed       4 IOCCNSID       Subchannel ID of virtual console
           Work area used for the CMS SET CMS370AC command.
             This work area is used to store the I/O New PSW and the
             External New PSW when the SET CMS370AC command is set ON.
    0628 1576 Dbl-Word     8 IOC370AC (0)   CMS SET CMS370AC command area
    0628 1576 Dbl-Word     8 IOCIOPSW       Area to store the I/O New PSW
    0630 1584 Dbl-Word     8 IOCEXPSW       Area to store the External New
                                            PSW
    0638 1592 Bitstring    1 IOC370FL       CMS SET CMS370AC flag byte
              1... ....      IOCMS370       X'80' When ON indicates CMS370AC
                                            active (The initial setting is
                                            OFF)
              .1.. ....      IOCCP370       X'40' When ON indicates CMS370AC
                                            turned CP SET 370ACCOM ON
    0639 1593 Bitstring    3 IO370RES       Reserved bytes in CMS370AC area
              0000063C       IOCSIZE        *-IOCON Length of I/O Console
                                            workarea
              000000C8       IOCDBSZ        ((IOCSIZE+7)/8) Size of IOCON in
                                            doublewords

#### IOCON Storage Layout

    *** IOCON - Console I/O Workarea
    *
    *     +-------------------------------------------------------+
    *   0 |                                                       |
    *     =                       IOCPATH                         =
    *     |                                                       |
    *     +-------------------------------------------------------+
    *  70 |///////////////////////////////////////////////////////|
    *     =///////////////////////////////////////////////////////=
    *     |///////////////////////////////////////////////////////|
    *     +-------------------------------------------------------+
    * 4D0 |                                                       |
    *     =                       IOCIDAL                         =
    *     |                                                       |
    *     +-------------------------------------------------------+
    * 570 |                       IOCSCCW                         |
    *     +-------------------------------------------------------+
    * 578 |                       IOCPCCW                         |
    *     +-------------------------------------------------------+
    * 580 |                       IOCCCWS                         |
    *     +-------------------------------------------------------+
    * 588 |                       IOCNCCW                         |
    *     +-------------------------------------------------------+
    * 590 |                       IOCSCCWX                        |
    *     +-------------------------------------------------------+
    * 598 |                       IOCPCCWX                        |
    *     +-------------------------------------------------------+
    * 5A0 |                       IOCCCWSX                        |
    *     +-------------------------------------------------------+
    * 5A8 |                       IOCNCCWX                        |
    *     +---------------------------+---------------------------+
    * 5B0 |         IOCWKCCF          |         IOCWKCCW          |
    *     +------+------+-------------+---------------------------+
    * 5B8 |:WKUST|:WKCST|  IOCWKRCT   |         IOCICCFL          |
    *     +------+------+-------------+------+------+-------------+
    * 5C0 |         IOCICCW           |:IUST |:ISCST|  IOCIRCT    |
    *     +---------------------------+------+------+-------------+
    * 5C8 |                                                       |
    *     =                       IOCIESW                         =
    *     |                           +---------------------------+
    *     |                           |                           |
    *     +---------------------------+                           |
    * 5E0 |                                                       |
    *     =                       IOCIECW                         =
    *     |                           +---------------------------+
    * 5F8 |                           |         IOCOINTP          |
    *     +------+------+------+------+---------------------------+
    * 600 |:OKSR |:OFPIN|:OLPM |:ORES |         IOCOCPA           |
    *     +------+------+------+------+---------------------------+
    * 608 |:WFLG1|:WAMOD|  IOCWFLGS   |         IOCWRES           |
    *     +------+------+-------------+                           |
    *     |                                                       |
    *     +------+------------------------------------------------+
    * 618 |:CFLG1|                    IOCCRES                     |
    *     +------+--------------------+---------------------------+
    * 620 |         IOCCNSID          |///////////////////////////|
    *     +---------------------------+---------------------------+
    * 628 |                       IOCIOPSW                        |
    *     +-------------------------------------------------------+
    * 630 |                       IOCEXPSW                        |
    *     +------+--------------------+---------------------------+
    * 638 |:370FL|     IO370RES       | 63C
    *     +------+--------------------+
    *
    *** IOCON - Console I/O Workarea

#### IOCON Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    IOCCCWS        0580
    IOCCCWSX       05A0
    IOCCDEV        0070
    IOCCFLDT       0618 10
    IOCCFLG1       0618
    IOCCISDT       0618 08
    IOCCLMIO       0618 40
    IOCCNSID       0620
    IOCCOMM        0618
    IOCCP370       0638 40
    IOCCRECO       0618 80
    IOCCRES        0619
    IOCCSHDT       0618 20
    IOCDBSZ        0639 000000C8
    IOCEXPSW       0630
    IOCIATTN       05C4 80
    IOCIBUSY       05C4 10
    IOCICCFL       05BC
    IOCICCW        05C0
    IOCICHEN       05C4 08
    IOCICUE        05C4 20
    IOCIDAL        04D0
    IOCIDVEN       05C4 04
    IOCIECW        05DC
    IOCIESW        05C8
    IOCIOPSW       0628
    IOCIRB         05BC
    IOCIRCT        05C6
    IOCISCST       05C5
    IOCISCSW       05BC
    IOCISTMD       05C4 40
    IOCIUNCK       05C4 02
    IOCIUNEX       05C4 01
    IOCIUST        05C4
    IOCMS370       0638 80
    IOCNCCW        0588
    IOCNCCWX       05A8
    IOCOCPA        0604
    IOCOFORM       0601 80
    IOCOFPIN       0601
    IOCOINTP       05FC
    IOCOKSR        0600
    IOCOLPM        0602
    IOCOPREF       0601 40
    IOCORB         05FC
    IOCORES        0603
    IOCPATH        0000
    IOCPCCW        0578
    IOCPCCWX       0598
    IOCSCCW        0570
    IOCSCCWX       0590
    IOCSIZE        0639 0000063C
    IOCWAMOD       0609
    IOCWASYN       0608 80
    IOCWCP11       0608 40
    IOCWCP20       0608 20
    IOCWFLGS       060A
    IOCWFLG1       0608
    IOCWKCCF       05B0
    IOCWKCCW       05B4
    IOCWKCST       05B9
    IOCWKCSW       05B0
    IOCWKRCT       05BA
    IOCWKUST       05B8
    IOCWLMQ        0608 10
    IOCWORK        0608
    IOCWRES        060C
    IOC370AC       0628
    IOC370FL       0638
    IO370RES       0639

This information is based on z/VM V5R2.0.
Last updated on 6 Dec 2005 at 15:35:13 EDT.
Copyright IBM Corporation, 1990, 2005