HCCW Back to Index page
 
Prolog 
Control Block Contents 
   HCCW 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.


  HCCW Prolog Top of page
 
 NAME       : HCPHCCW
 DESCRIPTION: HOST CHANNEL CONTROL WORD
 DSECT      : HCCW
 FUNCTION   : PROVIDE SYMOLIC REFERENCES FOR THE FIELDS OF THE FORMAT
              ONE CCWS USED BY CP
 LOCATED BY : N/A
 CREATED BY : N/A
 DELETED BY : N/A
 RELOCATION CONSIDERATIONS : None
 
 
  HCCW Control Block Content Top of page
 

 HCCW DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure HCCW HOST CHANNEL CONTROL WORD 0000 0 Dbl-Word 8 HCCW1 (0) AN ENTIRE FORMAT 1 CCW 0000 0 Signed 4 HCCWCFCT (0) Format 1 CCW first word - cmd, flag, and count 0000 0 Bitstring 1 HCCWCMND CCW COMMAND CODE 0001 1 Bitstring 1 HCCWFLAG CCW FLAG BITS 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 0002 2 Signed 2 HCCWCNT CCW DATA COUNT 0004 4 Address 4 HCCWADDR CCW DATA ADDRESS 00000007 HCCWADRX *-1 CCW FINAL BYTE OF ADDRESS 0008 8 Dbl-Word 8 HCCWNEXT (0) CCW FOLLOWING CURRENT CCW 0000000F HCCWIS B'1111' ICM/STCM MASK FOR 31 BIT ADDRESS 00000004 HCCWMC 04 MVC/CLC LENGTH FOR 31 BIT ADDRESS 00000080 HCCWIDAL B'10000000' IDAL INVALID BIT MASK 00000008 HCCWLEN 8 LENGTH OF A SINGLE CCW (8 BYTES)
 
 
  HCCW Storage Layout Top of page
 
          
*** HCCW - HOST CHANNEL CONTROL WORD
*
*     +------+------+-------------+---------------------------+
*   0 |:WCMND|:WFLAG|  HCCWCNT    |         HCCWADDR          |
*     +------+------+-------------+---------------------------+
*
*** HCCW - HOST CHANNEL CONTROL WORD
 
 
  HCCW Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
CCWCC          0001 40
CCWDC          0001 80
CCWIDA         0001 04
CCWINVAL       0001 03
CCWMIDA        0001 01
CCWPCIR        0001 08
CCWSILI        0001 20
CCWSKIP        0001 10
CCWSUSPN       0001 02
CCWUNDEF       0001 01
HCCWADDR       0004
HCCWADRX       0004 00000007
HCCWCFCT       0000
HCCWCMND       0000
HCCWCNT        0002
HCCWFLAG       0001
HCCWIDAL       0008 00000080
HCCWIS         0008 0000000F
HCCWLEN        0008 00000008
HCCWMC         0008 00000004
HCCWNEXT       0008
HCCW1          0000
 
This information is based on z/VM 7.3.0 Last updated on 22 Jun 2022 at 15:51:03 EDT.
Copyright IBM Corporation, 1990, 2022