Manual

Operating Characteristics 3-21
3.3.6 Related Collection Events
Many of the GES-1993's collection events relate to process state changes. For a
complete listing of these, see "Appendix B -- Collection Events".
3.4 Data Collection
Note the three types of variables: Status Variable (SV), Data Variable (DV), and
Equipment Constants (EC). The Host sets only ECs. DVs are time stamped by being
associated with Collection Events Ids (CEID), and will be reported by FmNT in
Event Reports ([RefGWGEMUser] p 77 ‘Data Collection’).
FmNT specifies all of the CEIDs in the GCD file, including the ones standard for
GEM ([RefGWGEMUser] p 200 ‘Collection Events’). See Appendix B for a full list
of the collection events managed by FmNT.
3.4.1 Variables
The GES-1993 has a fixed set of Variables which can be read by the Host. Each
Variable is identified by a unique Variable ID (VID). The Variables which exist are
shown in "Appendix A -- Data Dictionary Variables".
There are three types of Variables: Status Variables, Data Variables, and Equipment
Constants. The Host can read Variables of any type, but can set values only for
Equipment Constants. The Host can read values for Status Variables and Equipment
Constant whenever the GES-1993 is On-Line, but values for Data Variables are
typically meaningful only immediately after certain Collection Events (CEIDs), and
so are typically reported only in Event Reports (S6F11).
Appendix A lists all Variables for both FmNT and standard GEM operations.
3.4.2 Are You There
The Host can send S1F1 at any time to determine if the SECS link is operational.
The GES-1993 responds with S1F2, if the equipment is in the ONLINE &
COMMUNICATING states. This indicates Model Number (MDLN) and Software
Revision Number (SOFTREV).
GWGEM automatically provides this service.