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

#### LDDBK

Prolog

Control Block Contents
LDDBK DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### LDDBK Prolog

     NAME       : HCPLDDBK
     DESCRIPTION: LOGICAL DISPLAY DEVICE SIMULATION BLOCK
     DSECT      : LDDBK
     FUNCTION   : THE LDDBK IS USED TO MAINTAIN INFORMATION NEEDED
                  TO EFFECTIVELY SIMULATE LOGICAL 327X AND 328X DEVICES.
                  THE DATA STRUCTURE THAT THESE BLOCKS RESIDE IN IS
                  MAINTAINED IN THE MODULE HCPLDA, AND THESE BLOCKS
                  ARE ONLY AVAILABLE VIA CALL TO THAT MODULE.
                  SEE HCPLDA FOR DETAILS.
     LOCATED BY : HCPLDAFE
     CREATED BY : HCPLDACR
     DELETED BY : HCPLDADD

#### LDDBK Control Block Content

#### LDDBK DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      LDDBK          LOGICAL DISPLAY DEVICE SIMULATION
                                            BLOCK
    0000    0 Dbl-Word     8 LDDBKID (0)    BLOCK IDENTIFIER
    0000    0 Character    5 LDDNAME        BLOCK NAME 'LDDBK'
    0005    5 Bitstring    1 LDDVERS        BLOCK VERSION NUMBER
              00000001       LDDCURVR       LDDMAR1 CURRENT VERSION OF THE
                                            LDDBK
              00000001       LDDMAR1        X'01' VM/XA MA RELEASE 1
    0006    6 Signed       2 LDDLDNUM       LOGICAL DEVICE NUMBER
    0008    8 Signed       4 LDDBUFAD       PENDING DATA BUFFER ADDRESS
    000C   12 Signed       4 LDDSUSP        CPEBK ADDRESS FOR SUSPENDED TASK
    0010   16 Signed       4 LDDCOUNT       PENDING CCW DATA COUNT
    0014   20 Bitstring    1 LDDCRCW        CURRENT CCW OPCODE
    0015   21 Bitstring    1 LDDSENSE       SENSE INFORMATION
    0016   22 Bitstring    1 LDDUSTTS       UNIT STATUS INFORMATION
    0017   23 Bitstring    1 LDDEXTCD       EXTERNAL INTERRUPT CODE TO
                                            REFLECT TO HOST MACHINE
              00000001       LDDKILLD       X'01' CP HAS TERMINATED THIS
                                            DEVICE
              00000002       LDDWRT         X'02' A WRITE WAS ISSUED TO THIS
                                            DEVICE
              00000003       LDDNTFY        X'03' A PREVIOUS PRESENT IS NOW
                                            COMPLETE
              00000004       LDDRDBUF       X'04' READ-BUFFER ISSUED TO THIS
                                            DEVICE
              00000005       LDDRDMOD       X'05' READ-MODIFIED ISSUED TO
                                            THIS DEVIC
    0018   24 Bitstring    1 LDDWTNG        FUNCTION WE ARE WAITING FOR
              1... ....      LDDACCWT       X'80' ACCEPT - WRITE CCW PENDING
              .1.. ....      LDDPRBWT       X'40' PRESENT - READ-BUFFER
                                            PENDING
              ..1. ....      LDDPRMWT       X'20' PRESENT - READ-MODIFIED
                                            PENDING
              ...1 ....      LDDSTAWT       X'10' WAITING FOR STATUS DIAGNOSE
              .... 1...      LDDWACWT       X'08' IN WRITE/ACCEPT CHAIN -
                                            DON'T MOVE CCW INTO DATA BUFFER
              .... .1..      LDDPREXT       X'04' PRESENT IN PROGRESS -
                                            REFLECT INTERRUPT CODE 3 ON
                                            COMPLETION
    0019   25 Bitstring    1 LDDCURPR       CURRENT PROCESSING FLAGS
              1... ....      LDDPRES        X'80' PRESENT IN PROGRESS
              .1.. ....      LDDACCPT       X'40' ACCEPT IN PROGRESS
              ..1. ....      LDDEXTRN       X'20' External interrupt being
                                            reflected (not reason code 3)
              ...1 ....      LDDMVPTL       X'10' MOVE PARTIAL DATA ON ACCEPT
              .... 1...      LDDPRDBU       X'08' PRESENT of read buffer data
              .... .1..      LDDEXT3        X'04' External interrupt reason
                                            code 3 being reflected
    001A   26 Bitstring    1 LDDSCHAR       SPECIAL DEVICE CHARACTERISTICS
              1... ....      LDDACCST       X'80' STATUS MUST FOLLOW ACCEPT
                                            FUNCTION
              .1.. ....      LDDEXTFT       X'40' EXTENDED FEATURES SUPPORTED
              ..1. ....      LDDNOEWA       X'20' Erase/Write Alternate NOT
                                            supported
              ...1 ....      LDDDEVID       X'10' Device identifier provided
              .... 1...      LDDDEVIP       X'08' Device identifier pointer
                                            provided
    001B   27 Bitstring    1 LDDSTATS       MISCELLANEOUS STATUS
              1... ....      LDDPURGE       X'80' PRESENT DATA BUFFER WAS
                                            PURGED
              .1.. ....      LDDCPBUF       X'40' BUFFER AT LDDBUFAD IS IN CP
                                            STORAGE.
              ..1. ....      LDDLERR        X'20' ERROR DETECTED DURING LIST
                                            FORM PRESENT
              ...1 ....      LDDDEAD        X'10' LOGICAL DEVICE IS DECEASED
              .... 1...      LDDBUFPG       X'08' Buffer at LDDBUFAD is a
                                            page and was obtained via
                                            HCPPTFGF
              .... .1..      LDDSELR        X'04' SELECTIVE RESET HAS BEEN
                                            DONE ON THIS LDDBK.
              .... ..1.      LDDNTYDN       X'02' PRESENT LIST FORMAT EXT INT
                                            DONE
              .... ...1      LDDHVM24       X'01' HVM addressing mode is 24
                                            bit
    001C   28 Signed       4 LDDBUFL        PENDING DATA BUFFER LENGTH -
                                            BYTES
    0020   32 Signed       4 LDDPARNT       VMDBK ADDRESS OF THE VIRTUAL
                                            MACHINE THAT CREATED THE LOGICAL
                                            DEVICE
    0024   36 Signed       4 LDDFPNTR       FORWARD POINTER TO NEXT LDDBK
    0028   40 Signed       4 LDDBPNTR       BACK POINTER TO PREVIOUS LDDBK
    002C   44 Signed       4 LDDRDEV        ADDRESS OF RDEV FOR LOGICAL
                                            DEVICE
    0030   48 Dbl-Word     8 LDDLOCK (3)    LDDBK LOCK SEMAPHORE
    0048   72 Bitstring   16 LDDIDENT       Logical device identifier
              0000000B       LDDSIZE        (*-LDDBK+7)/8 SIZE OF LDDBK IN
                                            DOUBLEWORDS

#### LDDBK Storage Layout

    *** LDDBK - LOGICAL DISPLAY DEVICE SIMULATION BLOCK
    *
    *     +----------------------------------+------+-------------+
    *   0 |             LDDNAME              |:VERS |  LDDLDNUM   |
    *     +---------------------------+------+------+-------------+
    *   8 |         LDDBUFAD          |         LDDSUSP           |
    *     +---------------------------+------+------+------+------+
    *  10 |         LDDCOUNT          |:CRCW |:SENSE|:USTTS|:EXTCD|
    *     +------+------+------+------+------+------+------+------+
    *  18 |:WTNG |:CURPR|:SCHAR|:STATS|         LDDBUFL           |
    *     +------+------+------+------+---------------------------+
    *  20 |         LDDPARNT          |         LDDFPNTR          |
    *     +---------------------------+---------------------------+
    *  28 |         LDDBPNTR          |         LDDRDEV           |
    *     +---------------------------+---------------------------+
    *  30 |                                                       |
    *     =                       LDDLOCK                         =
    *     |                                                       |
    *     +-------------------------------------------------------+
    *  48 |                       LDDIDENT                        |
    *     |                                                       |
    *     +-------------------------------------------------------+
    *  58
    *
    *** LDDBK - LOGICAL DISPLAY DEVICE SIMULATION BLOCK

#### LDDBK Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    LDDACCPT       0019 40
    LDDACCST       001A 80
    LDDACCWT       0018 80
    LDDBKID        0000
    LDDBPNTR       0028
    LDDBUFAD       0008
    LDDBUFL        001C
    LDDBUFPG       001B 08
    LDDCOUNT       0010
    LDDCPBUF       001B 40
    LDDCRCW        0014
    LDDCURPR       0019
    LDDCURVR       0005 00000001
    LDDDEAD        001B 10
    LDDDEVID       001A 10
    LDDDEVIP       001A 08
    LDDEXTCD       0017
    LDDEXTFT       001A 40
    LDDEXTRN       0019 20
    LDDEXT3        0019 04
    LDDFPNTR       0024
    LDDHVM24       001B 01
    LDDIDENT       0048
    LDDKILLD       0017 00000001
    LDDLDNUM       0006
    LDDLERR        001B 20
    LDDLOCK        0030
    LDDMAR1        0005 00000001
    LDDMVPTL       0019 10
    LDDNAME        0000
    LDDNOEWA       001A 20
    LDDNTFY        0017 00000003
    LDDNTYDN       001B 02
    LDDPARNT       0020
    LDDPRBWT       0018 40
    LDDPRDBU       0019 08
    LDDPRES        0019 80
    LDDPREXT       0018 04
    LDDPRMWT       0018 20
    LDDPURGE       001B 80
    LDDRDBUF       0017 00000004
    LDDRDEV        002C
    LDDRDMOD       0017 00000005
    LDDSCHAR       001A
    LDDSELR        001B 04
    LDDSENSE       0015
    LDDSIZE        0048 0000000B
    LDDSTATS       001B
    LDDSTAWT       0018 10
    LDDSUSP        000C
    LDDUSTTS       0016
    LDDVERS        0005
    LDDWACWT       0018 08
    LDDWRT         0017 00000002
    LDDWTNG        0018

This information is based on z/VM V5R2.0. Last updated on 12 Apr 2006 at 17:00:44 EDT.
Copyright IBM Corporation, 1990, 2005