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

#### NEDBK

Prolog

Control Block Contents
NEDBK DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### NEDBK Prolog

     NAME       : HCPNEDBK
     DESCRIPTION: Node Element Descriptor Block
     DSECT      : NEDBK
     FUNCTION   : Describes the Contents of a Node Element
                  Desciptor.
     LOCATED BY : CUITOKND - Pointer to the Token NED in an I/O
                  Subsystem.  Other NEDs are linked using
                  the Boeblingen Building Block N-ary Tree
                  Structure.
     CREATED BY : HCPCDT - Configuration Data Table Services
     DELETED BY : None.
     SERIALIZED : This block will be serialized by the RDEV lock.
     COMMENTS   : Data map is hand drawn.

#### NEDBK Control Block Content

#### NEDBK DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      NEDBK          Node Element Descriptor Block
    0000    0 Bitstring   32 NEDDATA (0)    Node Element Data
    0000    0 Bitstring    1 NEDFLAGS       Flags.
              111. ....      NEDFNVAL       X'E0' Node-ID Validity. Describes
                                            the validity of the node ID in
                                            bytes 4-31.
              11.. ....      NEDFLDID       X'C0' Field id = '11'b
              ..1. ....      NEDTOKEN       X'20' Token NED Indicator. If ON,
                                            the node described by this Node
                                            Element Descriptor (NED) is a
                                            Token NED.
              ...1 ....      NEDFTYP        X'10' Node Type. If ON, the node
                                            described by this Node Element
                                            Descriptor (NED) is a Central
                                            Processing Complex (CPC) type
                                            node. If OFF, the node described
                                            by this NED is a Device Type
                                            node.
              .... 1...      NEDFINFT       X'08' Interface Type. If ON, the
                                            attachable unit interface that
                                            determines this node is an
                                            internal interface. If OFF, the
                                            attachable unit interface that
                                            determines this node is an
                                            external interface.
              .... .1..      NEDFINFQ       X'04' Interface Qualifier. When
                                            (NEDFTYP = '1'B) & (NEDFINFT =
                                            '0'B) & (NEDFINFQ = '0'B) THEN
                                            the channel path interface has an
                                            associated CHPID. When (NEDFTYP =
                                            '1'B) & (NEDFINFT = '0'B) &
                                            (NEDFINFQ = '1'B) THEN the
                                            channel path interface has NO
                                            associated CHPID. For all other
                                            settings of flag bits 3 and 4, a
                                            zero in flag bit 5 has no
                                            meaning.
              .... ..1.      NEDFINVA       X'02' Node ID is not valid. The
                                            CPC is not
              .... ...1      NEDFNCUR       X'01' Node ID is valid, but may
                                            not be current.
              .... ....      NEDFVALN       X'00' Node ID is valid. able to
                                            obtain the requested node ID.
    0001    1 Bitstring    3 NEDNPARM       Node Parameters.
    0004    4 Bitstring    6 NEDTYPEN       TYPE NUMBER contains the EBCDIC
                                            type number (0-9) of the
                                            attachable unit.
    000A   10 Bitstring    3 NEDMODN        Model Number contains the EBCDIC
                                            model number (0-9 or upper case
                                            A-Z) of the attachable unit.
    000D   13 Bitstring    3 NEDMANUF       Manufacturer contains EBCDIC code
                                            (0-9 or upper-case A-Z) which
                                            identifies the manufacturer of
                                            the attachable unit e.g. "IBM".
    0010   16 Bitstring    2 NEDPMANF       Plant of Manufacture contains
                                            EBCDIC code (0-9 or upper-case
                                            A-Z) which identifies the plant
                                            of manufacture for the attach-
                                            able unit.
    0012   18 Bitstring   12 NEDSEQN (0)    Sequence Number.
    0012   18 Bitstring    7 NEDSEQN1       Sequence Number contains the
                                            EBCDIC code (0-9 or upper-case
                                            A-Z) which identifies the first 7
                                            chars of the sequence number of
                                            the attachable unit.
    0019   25 Bitstring    5 NEDSEQN2       Sequence Number contains the
                                            EBCDIC code (0-9 or upper-case
                                            A-Z) which identifies the last 5
                                            chars of the sequence number of
                                            the attachable unit.
    001E   30 Bitstring    2 NEDTAG         Tag contains physical identifier
                                            for an interface of the
                                            attachable unit.
    0020   32 Address      4 NEDSCPDT       NED Scope Function data which is
                                            used during the CDT Scope
                                            Function. Depending on the type
                                            of NED this block is used for,
                                            this filed will contain different
                                            data. If DNED, this field holds
                                            the RDEV address Otherwise, this
                                            field holds the CHPID list
                                            address.
                  Field Redefinitions
    0001    1 Bitstring    1 NEDTYPE        Type of NED
              00000001       NEDDEVND       X'01' I/O device NED
              00000002       NEDCUNED       X'02' Storage Control NED
    0002    2 Bitstring    1 * (2)          Reserved for future IBM use.
    0001    1 Bitstring    1 * (2)          Reserved for future IBM use.
    0003    3 Bitstring    1 NEDCHPID       Channel Path ID.
            Node parameter definition for a SWITCH Node
            Descriptor obtained from a Store Event Info
            CHSC after a link incident CRW was stored.
    0001    1 Bitstring    1 *              Reserved for future IBM use.
    0002    2 Bitstring    1 NEDCLASS       I/O Device Class
              .... 1.1.      NEDSWICH       X'0A' Switch
    0003    3 Bitstring    1 NEDLINKA       Link Address
    0020   32 Address      4 NEDRDEV        RDEV address if Device NED
    0020   32 Address      4 NEDCHPTR       Otherwise, CHPID list pointer
    0024   36 Address      4 NEDMPPTR       Pointer to a BBLX linked list of
                                            multiparent NEDBK addresses.
                Mappings for NEDTAG
          For a Volume NED
    001E   30 Bitstring    1 NEDLCU         ESCON Logical CU number.
    001F   31 Bitstring    1 NEDUA          Unit address of the Volume.
              00000005       NEDSIZE        (*-NEDBK+7)/8 Size of NEDBK in
                                            doublewords.
              00000028       NEDLEN         (*-NEDBK) Size of NEDBK in bytes.

#### NEDBK Storage Layout

    *** NEDBK - Node Element Descriptor Block
    *
    *     +------+--------------------+---------------------------+
    *   0 |:FLAGS|     NEDNPARM       |        NEDTYPEN-          |
    *     +------+------+-------------+------+--------------------+
    *   8 |   -(004)    |      NEDMODN       |     NEDMANUF       |
    *     +-------------+--------------------+--------------------+
    *  10 |  NEDPMANF   |               NEDSEQN1-                 |
    *     +------+------+---------------------------+-------------+
    *  18 |-(012)|            NEDSEQN2              |   NEDTAG    |
    *     +------+--------------------+-------------+-------------+
    *  20 |         NEDSCPDT          |///////////////////////////|
    *     +---------------------------+---------------------------+
    *  28
    *
    *** NEDBK - Node Element Descriptor Block

    *** Overlay for NEDNPARM in NEDBK
    *
    *            +------+-------------+
    *   0 ..   1 |:TYPE |/////////////| 4
    *            +------+-------------+
    *
    *** Overlay for NEDNPARM in NEDBK

    *** Overlay for NEDNPARM in NEDBK
    *
    *            +-------------+------+
    *   0 ..   1 |/////////////|:CHPID| 4
    *            +-------------+------+
    *
    *** Overlay for NEDNPARM in NEDBK

    *** Overlay for NEDNPARM in NEDBK
    *
    *            +------+------+------+
    *   0 ..   1 |//////|:CLASS|:LINKA| 4
    *            +------+------+------+
    *
    *** Overlay for NEDNPARM in NEDBK

    *** Overlay for NEDSCPDT in NEDBK
    *
    *     +---------------------------+
    *  20 |         NEDRDEV           | 24
    *     +---------------------------+
    *
    *** Overlay for NEDSCPDT in NEDBK

    *** Overlay for NEDSCPDT in NEDBK
    *
    *     +---------------------------+---------------------------+
    *  20 |         NEDCHPTR          |         NEDMPPTR          |
    *     +---------------------------+---------------------------+
    *  28
    *
    *** Overlay for NEDSCPDT in NEDBK

    *** Overlay for NEDTAG in NEDBK
    *
    *                                               +------+------+
    *  18 ...                                    1E |NEDLCU|NEDUA |
    *                                               +------+------+
    *  20
    *
    *** Overlay for NEDTAG in NEDBK

#### NEDBK Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    NEDCHPID       0003
    NEDCHPTR       0020
    NEDCLASS       0002
    NEDCUNED       0001 00000002
    NEDDATA        0000
    NEDDEVND       0001 00000001
    NEDFINFQ       0000 04
    NEDFINFT       0000 08
    NEDFINVA       0000 02
    NEDFLAGS       0000
    NEDFLDID       0000 C0
    NEDFNCUR       0000 01
    NEDFNVAL       0000 E0
    NEDFTYP        0000 10
    NEDFVALN       0000 00
    NEDLCU         001E
    NEDLEN         001F 00000028
    NEDLINKA       0003
    NEDMANUF       000D
    NEDMODN        000A
    NEDMPPTR       0024
    NEDNPARM       0001
    NEDPMANF       0010
    NEDRDEV        0020
    NEDSCPDT       0020
    NEDSEQN        0012
    NEDSEQN1       0012
    NEDSEQN2       0019
    NEDSIZE        001F 00000005
    NEDSWICH       0002 0A
    NEDTAG         001E
    NEDTOKEN       0000 20
    NEDTYPE        0001
    NEDTYPEN       0004
    NEDUA          001F

This information is based on z/VM V5R2.0. Last updated on 12 Apr 2006 at 17:06:47 EDT.
Copyright IBM Corporation, 1990, 2005