Owner's manual

3-32 Operating Characteristics
3.13 Spooling
When the SECS link between the Host and the Equipment goes down (RTY error on the Equipment
side), the Equipment will spool appropriate messages so that the Host can read them once the link comes
back up (after a successful Connect Request transaction).
The Host can set spooling attributes on the Equipment by setting certain equipment constants with the
S2F15/16 transaction.
The Host can define streams and functions of messages to be spooled through the S2F43/44 transaction.
Stream one (S1Fx) messages are not eligible for spooling. The Host can also disable spooling for
messages through this S2F43/44 transaction. Stream 9 messages are not spooled.
The Host may read spooled messages or purge the Equipment’s spool through the S6F23/24 transaction.
3.13.1 A Word of Caution
If the Host does not intend to use the spooling features of the Equipment, the equipment constant
ConfigSpool should be set to zero. Setting this EC to zero disables the spooling feature. If this is not set
to zero, and the Host does not support spooling, the SECS connection with the Equipment will be
crippled. This happens because of the following:
1. When spooling becomes active (transmission error), the Equipment will not send “Non-
Stream 1” primary messages to the Host. That is, it will not send events, alarms, process
programs, terminal display, etc.
2. When spooling becomes active, the ONLY way to deactivate it is to read (purge) or delete
the spool from the Host. In complying with the GEM standard, the Equipment does not have
the ability to reset its spooling state.
3. Therefore, if your Host does not support spooling and spooling becomes active, you will
never again receive non stream 1 messages from the Equipment. If this occurs, you will need
to use a Host simulator such as SECSIM to delete the spool.
3.13.2 Spooling Sequence
Messages are sent to the spool only if the Host has enabled these messages for spooling. This
precondition will not be repeated throughout this section. Assume that the messages referred to in this
section have been enabled for spooling.
While spooling is active, the Host may initiate primary messages and the Equipment will respond, if it is
in the COMMUNICATING state.
Figure 3-7 and Table 3-24 describe the spooling sequence. Refer to Table 3-24 for definition of numbers
used in the figure.