gtpd2m1pData Communications Services Reference

Core Table Headers Categories

Message switching core tables are loaded from 1055 byte file records. The amount of core required per table will determine how many file records are needed. Because of the programming techniques used in handling these core tables, the tables are divided into three categories.

Single File Record Core Table

These message switching core tables are composed from only one file record because of built-in limits.
XN1XN
XJ1LC
XE1SC
XP1XP

Multiple File Record Core Tables - Header Dropped

This group of core table records are loaded with headers dropped from all file records but the first record of that core table. The reason for this is that all data must be accessed from adjacent core locations. Therefore, the second record must be loaded consecutively into core after the first, etc.
XC1CC
XK1CT
XF1FF
XX1ON

Multiple File Record Core Tables - Header Not Dropped

The following core tables have provisions to skip header entries of other than the first file record comprising that core table. The file records must, however, be loaded consecutively one after the other.
XW1OC*
XY0XY*
XR1TR**

*
It should be noted that the XW1OC and XU2TQ can also be placed in Category B (Header Dropped). The XR1TR cannot be placed in Category B because it is keypointed from core.

**
XR1TR is keypointed from core. This is done to preserve indexes and status indicators over a restart.