ZCOM Tables and Data Structures

ZCOM Header Structure

HLABEL - ZMON identifier label

The identifier label contains the word ‘ZMON’ and provides compatibility with HP1000 version of ZCOM. The memory image file contains the word ‘TTGE’ in this position. The LDM overwrites this after the ZCOM subsystem has been initialized.

HZREVC - ZCOM revision code

TTGEN initializes this field with a 16-bit revision code, indicating the version of the table structures. This revision code is stored as four 4-bit digits. The first two digits represent the revision of a major release and the last two digits represent a minor release revision. Data structures and applications linked with a previous revision of the ZCOM software will be compatible if they have same major revision code. ZMON checks whether the revision code is acceptable. The different minor numbers indicate compatible revisions, such as bug fixes (as long as the major release revision code is the same).

HTREVC - TTGEN revision code

TTGEN inserts its integer revision code in this field in the memory image file. It is loaded into memory (unchanged) by ZMON and the LDM. This 16-bit revision code is stored in the same format as the ZCOM revision code (HZREVC). However, there is no validation of this field.

HNAME1 - Name of the TTGEN source file

Full path name of the source file used by TTGEN to generate the object file. This field is limited to 256 bytes and is null terminated.

HNAME2 - Name of TTGEN object file

Full path name of the TTGEN produced object file which was then used to startup (initialize) the ZCOM subsystem. This field is limited to 256 bytes and is null terminated.

HSNAME - ZCOM subsystem runtime instance name

Contains the contents of the System-Nameparameter supplied in the TTGEN configuration file. This field is limited to 80 bytes and is null terminated.

HSSOFF - System starting offset

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