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

#### GCCW

Prolog

Control Block Contents
GCCW DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### GCCW Prolog

     NAME       : HCPGCCW
     DESCRIPTION: GUEST CHANNEL CONTROL WORD MAPPING
     DSECT      : GCCW
     FUNCTION   : PROVIDE SYMOLIC REFERENCES FOR THE FIELDS OF A CCW
                  FOR A VIRTUAL MACHINE
     LOCATED BY : N/A
     CREATED BY : N/A
     DELETED BY : N/A

#### GCCW Control Block Content

#### GCCW DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      GCCW           GUEST CHANNEL CONTROL WORD
                                            MAPPING
    0000    0 Dbl-Word     8 GCCWDWRD       CCW STRUCTURE
    0000    0 Signed       4 GCCW0WD0 (0)   FIRST WORD OF CCW
    0000    0 Bitstring    1 GCCW0CMD       CCW COMMAND CODE
    0001    1 Address      3 GCCW0ADR       CCW ADDRESS (24-BIT)
    0004    4 Signed       4 GCCW0WD1 (0)   SECOND WORD OF CCW
    0004    4 Bitstring    1 GCCW0FLG       CONTROL OF CCW FLAGS
              1... ....      CCWDC          X'80' CHAIN DATA ADDRESS AND
                                            COUNT
              .1.. ....      CCWCC          X'40' COMMAND CHAIN
              ..1. ....      CCWSILI        X'20' SUPPRESS INCORRECT LENGTH
              ...1 ....      CCWSKIP        X'10' SUPPRESS INBOUND DATA
                                            TRANSFER
              .... 1...      CCWPCIR        X'08' REQUEST PC INTERRUPTION
              .... .1..      CCWIDA         X'04' INDIRECT DATA ADDRESSING
              .... ..11      CCWINVAL       X'03' I/O UNDEFINED PAIR OF BITS
              .... ..1.      CCWSUSPN       X'02' I/O SUSPENSION/RESUMPTION
              .... ...1      CCWUNDEF       X'01' I/O UNDEFINED BIT
    0005    5 Bitstring    1 GCCW0SPL       FORMAT 0 "UNUSED" BYTE.
    0006    6 Signed       2 GCCW0CNT       COUNT FOR I/O
    0008    8 Dbl-Word     8 GCCW0NXT (0)   NEXT GUEST CCW
              00000007       GCCW0IS        B'0111' INSERT MASK
              00000080       GCCW0IDL       B'10000000' IDAL INVALID BITS
                                            MASK
              00000008       GCCW0LEN       8 LENGTH OF A FORMAT 0 CCW
    0000    0 Signed       4 GCCW1WD0 (0)   FIRST WORD OF CCW
    0000    0 Bitstring    1 GCCW1CMD       CCW COMMAND CODE
    0001    1 Bitstring    1 GCCW1FLG       CONTROL OF CCW FLAGS
              1... ....      CCWDC          X'80' CHAIN DATA ADDRESS AND
                                            COUNT
              .1.. ....      CCWCC          X'40' COMMAND CHAIN
              ..1. ....      CCWSILI        X'20' SUPPRESS INCORRECT LENGTH
              ...1 ....      CCWSKIP        X'10' SUPPRESS INBOUND DATA
                                            TRANSFER
              .... 1...      CCWPCIR        X'08' REQUEST PC INTERRUPTION
              .... .1..      CCWIDA         X'04' INDIRECT DATA ADDRESSING
              .... ..11      CCWINVAL       X'03' I/O UNDEFINED PAIR OF BITS
              .... ..1.      CCWSUSPN       X'02' I/O SUSPENSION/RESUMPTION
              .... ...1      CCWUNDEF       X'01' I/O UNDEFINED BIT
    0002    2 Signed       2 GCCW1CNT       COUNT FOR I/O
    0004    4 Signed       4 GCCW1WD1 (0)   SECOND WORD OF CCW
    0004    4 Address      4 GCCW1ADR       CCW ADDRESS (31-BIT)
    0008    8 Dbl-Word     8 GCCW1NXT (0)   NEXT GUEST CCW
              0000000F       GCCW1IS        B'1111' INSERT MASK
              00000080       GCCW1IDL       B'10000000' IDAL INVALID BIT MASK
              00000008       GCCW1LEN       8 LENGTH OF A FORMAT 1 CCW

#### GCCW Storage Layout

    *** GCCW - GUEST CHANNEL CONTROL WORD MAPPING
    *
    *     +-------------------------------------------------------+
    *   0 |                       GCCWDWRD                        |
    *     +-------------------------------------------------------+
    *   8
    *
    *** GCCW - GUEST CHANNEL CONTROL WORD MAPPING

    *** Overlay for GCCWDWRD in GCCW
    *
    *     +------+--------------------+------+------+-------------+
    *   0 |:W0CMD|     GCCW0ADR       |:W0FLG|:W0SPL|  GCCW0CNT   |
    *     +------+--------------------+------+------+-------------+
    *
    *** Overlay for GCCWDWRD in GCCW

    *** Overlay for GCCWDWRD in GCCW
    *
    *     +------+------+-------------+---------------------------+
    *   0 |:W1CMD|:W1FLG|  GCCW1CNT   |         GCCW1ADR          |
    *     +------+------+-------------+---------------------------+
    *
    *** Overlay for GCCWDWRD in GCCW

#### GCCW Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    CCWCC          0004 40
    CCWCC          0001 40
    CCWDC          0004 80
    CCWDC          0001 80
    CCWIDA         0004 04
    CCWIDA         0001 04
    CCWINVAL       0004 03
    CCWINVAL       0001 03
    CCWPCIR        0004 08
    CCWPCIR        0001 08
    CCWSILI        0004 20
    CCWSILI        0001 20
    CCWSKIP        0004 10
    CCWSKIP        0001 10
    CCWSUSPN       0004 02
    CCWSUSPN       0001 02
    CCWUNDEF       0004 01
    CCWUNDEF       0001 01
    GCCWDWRD       0000
    GCCW0ADR       0001
    GCCW0CMD       0000
    GCCW0CNT       0006
    GCCW0FLG       0004
    GCCW0IDL       0008 00000080
    GCCW0IS        0008 00000007
    GCCW0LEN       0008 00000008
    GCCW0NXT       0008
    GCCW0SPL       0005
    GCCW0WD0       0000
    GCCW0WD1       0004
    GCCW1ADR       0004
    GCCW1CMD       0000
    GCCW1CNT       0002
    GCCW1FLG       0001
    GCCW1IDL       0008 00000080
    GCCW1IS        0008 0000000F
    GCCW1LEN       0008 00000008
    GCCW1NXT       0008
    GCCW1WD0       0000
    GCCW1WD1       0004

This information is based on z/VM V5R2.0. Last updated on 12 Apr 2006 at 16:57:42 EDT.
Copyright IBM Corporation, 1990, 2005