S0CCW | Back to Index page

| Prolog Control Block Contents S0CCW DSECT Storage Layout Cross Reference (Contains links to field and bit definitions) |
Programming Interface Information: This information is NOT intended to be used as Programming Interfaces of z/VM.

S0CCW Prolog | Top of page

     NAME       : HCPS0CCW
     DESCRIPTION: SPOOLing Format 0 Channel Control
                  Word Pairs
     DSECT      : S0CCW
     FUNCTION   : Provide symbolic references for the fields of
                  the format 0 (370) CCW pairs used by spooling
                  in the spool files.  The format 0 CCW is used
                  when working with VM/SP spool files.  This
                  definition corresponds to the VM/SP CCW pair
                  usage.
     LOCATED BY : N/A
     CREATED BY : N/A
     DELETED BY : N/A
     RELOCATION CONSIDERATIONS : None

S0CCW Control Block Content | Top of page

     S0CCW DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      S0CCW          SPOOLing Format 0 Channel Control
    0000    0 Bitstring   12 S0CCWPAR (0)   FORMAT 0 (System 370 CCW Pair)
    0000    0 Signed       4 S0CCWWD0 (0)   First word of CCW pair
    0000    0 Bitstring    1 S0CCWCMD       CCW command code
    0001    1 Address      3 S0CCWADR       CCW address (24-BIT)
    0004    4 Signed       4 S0CCWWD1 (0)   Second word of CCW pair
    0004    4 Bitstring    1 S0CCWFLG       Control of CCW flags
              1... ....      CCWDC          X'80' CCWDC CHAIN DATA ADDRESS
                                            AND COUNT
              .1.. ....      CCWCC          X'40' CCWCC COMMAND CHAIN
              ..1. ....      CCWSILI        X'20' CCWSILI SUPPRESS INCORRECT
                                            LENGTH
              ...1 ....      CCWSKIP        X'10' CCWSKIP SUPPRESS INBOUND
                                            DATA TRANSFER
              .... 1...      CCWPCIR        X'08' CCWPCIR REQUEST PC
                                            INTERRUPTION
              .... .1..      CCWIDA         X'04' CCWIDA INDIRECT DATA
                                            ADDRESSING
              .... ..11      CCWINVAL       X'03' CCWINVAL I/O UNDEFINED PAIR
                                            OF BITS
              .... ..1.      CCWSUSPN       X'02' CCWSUSPN I/O
                                            SUSPENSION/RESUMPTION The
                                            CCWUNDEF definition is left here
                                            because some code still uses this
                                            field where the CCWMIDA bit is
                                            not applicable.
              .... ...1      CCWUNDEF       X'01' CCWUNDEF I/O UNDEFINED BIT
              .... ...1      CCWMIDA        X'01' CCWMIDA
                                            Modified-CCW-indirect-data-addres
                                            sing
    0005    5 Bitstring    1 S0CCWUN        FORMAT 0 "UNUSED" byte.
    0006    6 Signed       2 S0CCWCNT       Count for I/O
              00000008       S0CCWSLN       (*-S0CCW) Length of a FORMAT 0
                                            CCW if the SKIP bit is set. (No
                                            TIC)
    0008    8 Signed       4 S0CCWWD2 (0)   Third word of CCW pair
    0008    8 Bitstring    1 S0CCWTCC       TIC CCW command code
    0009    9 Address      3 S0CCWTCA       TIC CCW address (24-BIT)
    000C   12 Signed       2 S0CCWDAT (0)   Start of variable length data
              0000000C       S0CCWLEN       (*-S0CCW) Length of a FORMAT 0
                                            CCW pair in bytes
                 S0CCWOL is a 2 byte field used to contain the
                 original data length for CCWs which have had
                 blanks compressed from the data.  This field is
                 nonexistent for CCWs in which compression does not
                 occur.
                 The exception is TAG processing which always has
                 the original data length appended to the end of
                 the tag data field.
                 S0CCWOL is located following the data.
                 However, direct addressability cannot be achieved
                 due to the preceding variable length data field.
    000C   12 Bitstring    2 S0CCWOL        Value of the original data length
              00000010       S0CCWTAG       (((S0CCWLEN+L'S0CCWOL+7)/8)*8)
                                            Length to add to the tag for the
                                            CCW and the original data length.
                                            Doubleword alignment is
                                            guaranteed through this
                                            computation.
              00000007       S0CCWIS        B'0111' Insert mask for 24-bit
                                            addresses

S0CCW Storage Layout | Top of page

    *** S0CCW - SPOOLing Format 0 Channel Control
    *
    *     +------+--------------------+------+------+-------------+
    *   0 |:CWCMD|     S0CCWADR       |:CWFLG|:CWUN |  S0CCWCNT   |
    *     +------+--------------------+------+------+-------------+
    *   8 |:CWTCC|     S0CCWTCA       |  S0CCWOL    | E
    *     +------+--------------------+-------------+
    *
    *** S0CCW - SPOOLing Format 0 Channel Control

S0CCW Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    CCWCC          0004 40
    CCWDC          0004 80
    CCWIDA         0004 04
    CCWINVAL       0004 03
    CCWMIDA        0004 01
    CCWPCIR        0004 08
    CCWSILI        0004 20
    CCWSKIP        0004 10
    CCWSUSPN       0004 02
    CCWUNDEF       0004 01
    S0CCWADR       0001
    S0CCWCMD       0000
    S0CCWCNT       0006
    S0CCWDAT       000C
    S0CCWFLG       0004
    S0CCWIS        000C 00000007
    S0CCWLEN       000C 0000000C
    S0CCWOL        000C
    S0CCWPAR       0000
    S0CCWSLN       0006 00000008
    S0CCWTAG       000C 00000010
    S0CCWTCA       0009
    S0CCWTCC       0008
    S0CCWUN        0005
    S0CCWWD0       0000
    S0CCWWD1       0004
    S0CCWWD2       0008

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:31:11 EDT.
Copyright IBM Corporation, 1990, 2020