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

#### DEVSECT

Prolog

Control Block Contents
DEVSECT DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### DEVSECT Prolog

     Name       : DEVSECT
     Description: Device Table Entry Mapping
     DSECT      : DEVSECT
     Function   : Describes the device information
                  required for input/output routines. DEVSECT is
                  a DSECT corresponding to the data in a DEVTAB
                  entry.

#### DEVSECT Control Block Content

#### DEVSECT DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      DEVSECT        Device Table Entry Mapping
    0000    0 Signed       2 DEVADDR        - VIRTUAL DEVICE ADDRESS
    0002    2 Bitstring    1 DEVFLAG        - D*1 - DEVICE FLAGS
              1... ....      DEVPSDOW       X'80' Pseudo wait bit (from
                                            WAITD)
              .1.. ....      DEVASAP        X'40' HNDINT/HNDIO issued with
                                            ASAP
              ..1. ....      DEVINTR        X'20' Interrupt received for this
                                            entry
              ...1 ....      DEVINTP        X'10' Interrupt processed
              .... 1...      DEVKEEP        X'08' KEEP past end-of-command
              .... .1..      DEVABNKP       X'04' Keep beyond ABEND
                                            processing
              .... ..1.      DEVPERST       X'02' Keep beyond DET/DEF
                                            processing
              .... ...1      DEVAM31        X'01' SLIH invoked as AMODE=31
    0002    2 Bitstring    1 DEVCLASS       Device class (DASD only)
    0003    3 Bitstring    1 DEVTYPE        Device type code
    0004    4 Signed       4 DEVNAME        - SYMBOLIC DEVICE NAME
    0008    8 Signed       4 DEVIPRA        - INTERRUPT PROCESSING ROUTINE
                                            ADDRESS
          DEVMISC definitions for tape devices
    000C   12 Signed       4 DEVMISC (0)    - MISCELLANEOUS - DEVICE
                                            DEPENDENT
    000C   12 Bitstring    1 DEVFMTA        TAPEIO format code last used by
                                            TAPE or VMFPLC2 with this tape
    000D   13 Bitstring    1 DEVFMTB        - TAPEIO format code last used
                                            with this tape device. This value
                                            is used in OS simulation
                                            alternate tape switching.
              0000000D       DEVMODE        DEVFMTB,1,C'X' Old name for
                                            DEVFMTB
    000E   14 Bitstring    2 DEVSNS (0)     Sense Bytes 0 and 1
    000E   14 Bitstring    1 DEVSNS0        from last unit check
    000F   15 Bitstring    1 DEVSNS1        from this device
          DEVMISC definitions for disk devices
    000C   12 Bitstring    1 DEVDFLAG       DASD flags
              1... ....      DEVDECKD       X'80' ECKD capable hardware
                                            attached
    000D   13 Bitstring    1 *              Reserved
    000E   14 Bitstring    2 DEVTNUM        Device Type Number, e.g. x'3390'
    000C   12 Signed       4 DEVPSW1        First half of saved PSW
    0010   16 Dbl-Word     8 DEVCSW         CSW
    0018   24 Address      4 DEVUWORD
    001C   28 Address      4 DEVIBKAD       Address of INTBLOK
    0020   32 Address      4 DEVIBKLN       Length of INTBLOK (bytes)
    0024   36 Signed       4 DEVPSW2        Second half of saved PSW
              00000028       DEVSIZE        *-DEVSECT DEVICE TABLE SIZE (IN
                                            BYTES)

#### DEVSECT Storage Layout

    *** DEVSECT - Device Table Entry Mapping
    *
    *     +-------------+------+
    *   0 |  DEVADDR    |:FLAG | 3
    *     +-------------+------+
    *
    *** DEVSECT - Device Table Entry Mapping

    *** Overlay for DEVFLAG in DEVSECT
    *
    *                   +------+------+---------------------------+
    *   0 ...         2 |:CLASS|:TYPE |         DEVNAME           |
    *     +-------------+------+------+------+------+------+------+
    *   8 |         DEVIPRA           |:FMTA |:FMTB |:SNS0 |:SNS1 |
    *     +---------------------------+------+------+------+------+
    *  10
    *
    *** Overlay for DEVFLAG in DEVSECT

    *** Overlay for DEVMISC in DEVSECT
    *
    *                                 +------+------+-------------+
    *   8 ...                       C |:DFLAG|//////|  DEVTNUM    |
    *                                 +------+------+-------------+
    *  10
    *
    *** Overlay for DEVMISC in DEVSECT

    *** Overlay for DEVMISC in DEVSECT
    *
    *                                 +---------------------------+
    *   8 ...                       C |         DEVPSW1           |
    *     +---------------------------+---------------------------+
    *  10 |                        DEVCSW                         |
    *     +---------------------------+---------------------------+
    *  18 |         DEVUWORD          |         DEVIBKAD          |
    *     +---------------------------+---------------------------+
    *  20 |         DEVIBKLN          |         DEVPSW2           |
    *     +---------------------------+---------------------------+
    *  28
    *
    *** Overlay for DEVMISC in DEVSECT

#### DEVSECT Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    DEVABNKP       0002 04
    DEVADDR        0000
    DEVAM31        0002 01
    DEVASAP        0002 40
    DEVCLASS       0002
    DEVCSW         0010
    DEVDECKD       000C 80
    DEVDFLAG       000C
    DEVFLAG        0002
    DEVFMTA        000C
    DEVFMTB        000D
    DEVIBKAD       001C
    DEVIBKLN       0020
    DEVINTP        0002 10
    DEVINTR        0002 20
    DEVIPRA        0008
    DEVKEEP        0002 08
    DEVMISC        000C
    DEVMODE        000D 0000000D
    DEVNAME        0004
    DEVPERST       0002 02
    DEVPSDOW       0002 80
    DEVPSW1        000C
    DEVPSW2        0024
    DEVSIZE        0024 00000028
    DEVSNS         000E
    DEVSNS0        000E
    DEVSNS1        000F
    DEVTNUM        000E
    DEVTYPE        0003
    DEVUWORD       0018

This information is based on z/VM V5R2.0.
Last updated on 6 Dec 2005 at 15:38:08 EDT.
Copyright IBM Corporation, 1990, 2005