Owner manual

Operating Characteristics 3-5
3.1.1.2 Communications States
The current Communication State will be one of the following values. There is no
Variable indicating the Communication State. The communication State is presented
to the Operator on the main Operator Interface screen.
3.1.1.2.1 DISABLED
The SECS link to the Host is disabled at the GES-1993. The Equipment will send no
messages to the Host. The Equipment will not respond to a Host-initiated ENQ.
3.1.1.2.2 ENABLED
When communications are Enabled, the Equipment's intention is to be in
communication with the Host. Whether or no the GES-1993 is currently
communicating with the Host determines which sub-state of the Enabled super-state
the GES-1993 is in.
3.1.1.2.3 ENABLED/COMMUNICATING
The SECS link between the GES-1993 and the Host is operating normally.
Periodically, the Equipment will send a "Heartbeat" message S1F1 to ensure that the
link is still operating. The heartbeat frequency is controlled by Equipment Constant
HEARTBEAT. HEARTBEAT (VID 26) can range from 0 to 32000, with default
value 30.
If the Equipment encounters a SECS-I Retry Limit (RTY) error when attempting to
send a block to the Host, it discards any messages queued for send and the
communication state transits to ENABLED.
3.1.1.2.4 ENABLED/NOT COMMUNICATING
The SECS link to the Host is enabled at the GES-1993, and the Equipment is
attempting to determine if the link is active. The Equipment periodically sends
S1F13 (Establish Communications Request).
If the connect is not successful for any reason, the Equipment will try again
periodically forever. The time between attempts is controlled by the Equipment
Constant ESTABLISHCOMMUNICATIONSTIMER. This variable (VID 44) can
range from 0 to 32000 seconds, with default of 60 seconds.
Once the Host has responded with S1F14 (Establish Communications
Acknowledge), the Communication State will change to COMMUNICATING.