LEDA Back to Index page
 
Prolog 
Control Block Contents 
   LEDA 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.


  LEDA Prolog Top of page
  
 NAME       : HCPLEDA
 DESCRIPTION: Locate Record Extended data area
 DSECT      : LEDA
 FUNCTION   : Maps the contents of the Locate Record
              Extended data area.
 LOCATED BY :
              HCCWADDR - The Locate Record Extended CCW data
              address field contains the address of
              the locate record extended data area.
 CREATED BY :
              Storage for this control block cannot be
              specifically allocated/deallocated using
              HCPGETST/HCPRELST.
              Track cache manager -
              Data area is part of a larger free storage
              area used to build ECKD channel programs
              which is allocated in modules HCPFMU/HCPFMP.
 DELETED BY :
              Storage for this control block cannot be
              specifically allocated/deallocated using
              HCPGETST/HCPRELST.
              Track cache manager -
              Data area is part of a larger free storage
              area used to build ECKD channel programs
              which is deallocated in modules HCPFMU/HCPFMP.
 SERIALIZED :
              Track cache manager -
              TCMTSLK  - Track cache lock
 RELOCATION CONSIDERATIONS : None
 COMMENTS   :
              Track cache manager -
              None
 
 
  LEDA Control Block Content Top of page
  




 LEDA DSECT
Top of page


Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      LEDA           Locate Record Extended data area
0000    0 Bitstring   16 LEDAREA (0)    Locate Record Extended data area
             Byte 0 (Operation byte)
             Although defined as BITs, the contents of the
             operation byte are, architecturally, multiple
             codes.
0000    0 Bitstring    1 LEDOP          Operation byte
          11.. ....      LEDOR          X'C0' LEDOR Operation byte, bits
                                        0 and 1 ------- Codes for use
                                        with LEDOR
          .... ....      LEDORCA        X'00' LEDORCA Orient on count
                                        area
          .1.. ....      LEDORHA        X'40' LEDORHA Orient on home
                                        address
          1... ....      LEDORDA        X'80' LEDORDA Orient on data area
          11.. ....      LEDORIX        X'C0' LEDORIX Orient on index
                                        -------
          ..11 1111      LEDOOC         X'3F' Operation byte, bits 2
                                        through 7 ------- Codes for use
                                        with LEDOOC
          .... ...1      LEDOCWD        X'01' Write data
          .... ..11      LEDOCFW        X'03' Format write
          .... .11.      LEDOCRD        X'06' Read data
          .... 1.11      LEDOCWT        X'0B' Write track
          .... 11..      LEDOCRT        X'0C' Read tracks
          ...1 .11.      LEDOCR         X'16' Read
          ..11 1111      LEDOCX         X'3F' Extended Op Code -------
             Byte 1 (Auxiliary byte)
0001    1 Bitstring    1 LEDAUX         Auxiliary byte
          1... ....      LEDAVTLF       X'80' LEDAVTLF Validate transfer
                                        length factor
          .... ...1      LEDARCS        X'01' LEDARCS Read count suffix
             Byte 2 (Zeros)
0002    2 Bitstring    1 LEDZEROS       Must be zeros
             Byte 3 (Count)
0003    3 Bitstring    1 LEDCOUNT       Count
             Bytes 4 through 7 (Seek address)
0004    4 Bitstring    4 LEDSEEK (0)    Seek address (CCHH)
0004    4 Bitstring    2 LEDSCC         CC of CCHH
0006    6 Bitstring    2 LEDSHH         HH of CCHH
             Bytes 8 through 12 (Search argument)
0008    8 Bitstring    5 LEDSRCH (0)    Search argument (CCHHR)
0008    8 Bitstring    2 LEDRCC         CC of CCHHR
000A   10 Bitstring    2 LEDRHH         HH of CCHHR
000C   12 Bitstring    1 LEDRR          R of CCHHR
             Byte 13 (Sector number)
000D   13 Bitstring    1 LEDSECT        Sector number
          1111 1111      LEDNOSCT       X'FF' LEDNOSCT Sector orientation
                                        not performed
             Bytes 14 and 15 (Transfer length factor)
000E   14 Bitstring    2 LEDTLF         Transfer length factor
             Byte 16  (Reserved)
0010   16 Bitstring    1 LEDRES         Reserved for IBM use
             Byte 17  (Extended Operation)
0011   17 Bitstring    1 LEDEOP         Extended Operation
          .... ....      LEDOTHOP       X'00' LEDOTHOP Use operation code
                                        in byte 0
          .... 1..1      LEDWRANY       X'09' LEDWRANY Write Any
          .... 1.1.      LEDRDANY       X'0A' LEDRDANY Read Any
          .... 111.      LEDRDTKS       X'0E' LEDRDTKS Read Trackset
          ...1 ....      LEDPRETS       X'10' LEDPRETS Prestage Trackset
          ...1 ...1      LEDWRTKS       X'11' LEDWRTKS Write Trackset
          ...1 ..11      LEDUWRTK       X'13' LEDUWRTK Update Write
                                        Trackset
             Bytes 18-19 (Extended Parameter Length)
0012   18 Bitstring    2 LEDEPLEN       Extended Parameter Length
             Bytes 20-21 (Extended Parameter)
0014   20 Bitstring    1 LEDEPRM1       Extended Parameter byte 1
0015   21 Bitstring    1 LEDEPRM2       Extended Parameter byte 2
             Length equates
          00000016       LEDBSIZE       *-LEDAREA Size of LEDA in bytes
          00000003       LEDSIZE        ((*-LEDAREA)+7)/8 Size of LEDA in
                                        DWs
 
 
  LEDA Storage Layout Top of page
  
          
*** LEDA - Locate Record Extended data area
*
*     +------+------+------+------+-------------+-------------+
*   0 |LEDOP |LEDAUX|:ZEROS|:COUNT|   LEDSCC    |   LEDSHH    |
*     +------+------+------+------+------+------+-------------+
*   8 |   LEDRCC    |   LEDRHH    |LEDRR |:SECT |   LEDTLF    |
*     +------+------+-------------+------+------+-------------+
*  10 |LEDRES|LEDEOP|  LEDEPLEN   |:EPRM1|:EPRM2| 16
*     +------+------+-------------+------+------+
*
*** LEDA - Locate Record Extended data area
 
 
  LEDA Cross Reference Top of page
  
 
Symbol         Dspl Value
-------------- ---- -----
LEDARCS        0001 01
LEDAREA        0000
LEDAUX         0001
LEDAVTLF       0001 80
LEDBSIZE       0015 00000016
LEDCOUNT       0003
LEDEOP         0011
LEDEPLEN       0012
LEDEPRM1       0014
LEDEPRM2       0015
LEDNOSCT       000D FF
LEDOCFW        0000 03
LEDOCR         0000 16
LEDOCRD        0000 06
LEDOCRT        0000 0C
LEDOCWD        0000 01
LEDOCWT        0000 0B
LEDOCX         0000 3F
LEDOOC         0000 3F
LEDOP          0000
LEDOR          0000 C0
LEDORCA        0000 00
LEDORDA        0000 80
LEDORHA        0000 40
LEDORIX        0000 C0
LEDOTHOP       0011 00
LEDPRETS       0011 10
LEDRCC         0008
LEDRDANY       0011 0A
LEDRDTKS       0011 0E
LEDRES         0010
LEDRHH         000A
LEDRR          000C
LEDSCC         0004
LEDSECT        000D
LEDSEEK        0004
LEDSHH         0006
LEDSIZE        0015 00000003
LEDSRCH        0008
LEDTLF         000E
LEDUWRTK       0011 13
LEDWRANY       0011 09
LEDWRTKS       0011 11
LEDZEROS       0002
 
This information is based on z/VM 7.1.0 Last updated on 22 Jun 2018 at 11:50:29 EDT.
Copyright IBM Corporation, 1990, 2018