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cycle. The pending fields (designation_state.pending_dna and designation_state.pending_protec-
tion_mode) store the requested target designation for this Target. The pending settings are originally
stored in RECEIVETARGETDESIGNATION but are updated in UPDATETARGETDESIGNATIONVA-
LIDITY whenever the Target is automatically undesignated. Otherwise, SETTARGETDESIGNATION
leaves the stored active and pending settings unmodified. Instead, it uses local variables (active_-
dna, pending_dna, and pending_protection_mode) to configure the target designation setting to be
provided to the TRM. The bulk of SETTARGETDESIGNATION involves setting those local variables
and that will be described next.
The local value of pending DNA (pending_dna) is initialized to the stored setting of pending DNA
(designation_state.pending_dna). The final value of pending_dna will be stored in intruder.dna in
the TRMINTRUDERINPUT output. A pending designation for DNA is not honored (is suspended)
when the Target is not valid for TRM processing or there are multiple threats and this Target is one
of the threats. A threat is a Target for which the TRM has generated an RA. In those cases, DNA is
deactivated (pending_dna is set to false) and designation_state.status is set to reflect the reason for
the suspension. When the Target is one of multiple threats, active_dna is set to false to reflect the
temporary suspension of DNA processing.
SETTARGETDESIGNATION next determines if CSPO-3000 can be used, independent of the status of
DNA (ok_cspo3000). First, the local value of pending protection mode (pending_protection_mode)
is initialized. If the pending designation for DNA was honored, pending_protection_mode is initial-
ized to the stored setting of pending protection mode (designation_state.pending_protection_mode).
Otherwise, the stored setting of active protection mode (designation_state.active_protection_mode)
is used to initialize the local value of pending protection mode (pending_protection_mode). Do-
ing so allows an active CSPO-3000 designation to be maintained, if possible. The final value of
pending_protection_mode will be stored in intruder.protection_mode.
A pending designation for protection mode is not honored (is suspended) when the Target is not
valid for TRM RA processing. A pending designation for protection mode is also not honored (is
delayed) when the protection mode used for TRM processing would change and there is an active
RA on the Target (designation_state.active_ra is true). In either case, designation_state.status is set
to reflect the reason for the suspension or delay.
Designation to DNA requires the protection mode to be S_standard_protection_mode. SETTAR-
GETDESIGNATION ensures that if the Target will be processed for DNA, the pending protection
mode is S_standard_protection_mode and not PROTECTION_MODE_Xo_CSPO3k. Similarly, if
the Target will be processed for CSPO-3000, SETTARGETDESIGNATION ensures the flag for pend-
ing DNA will be false. If the protection mode change is delayed, the flag for pending DNA is set to
the value of active_dna. Using the value of active_dna preserves the active DNA designation until
the Xo mode is switched to CSPO-3000.
SETTARGETDESIGNATION finishes by calling SETINTRUDERDESIGNATIONDATA to populate fields
in TRMINTRUDERINPUT (intruder) based on the local values of pending_dna and pending_pro-
tection_mode and on the valid and status fields in D ESIGNATIONSTATE (designation_state).
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ACAS Xa/Xo MOPS, Vol. II
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