Specifications

Sheet 38 of 39 Document 12245 Rev. I
b
CONTROL_MODE_LOCAL_OR_MAINTENANCE
= Control Mode is set to Local or Maintenance.
b
CONTROL_MODE_REMOTE_OR_MAINTENANCE
= Control Mode is set to Remote or Maintenance.
b
OTHER_UNIT_ONLINE
= The other unit (in a 1:1 system) is on line, or there is a
problem reading the switch position, or the switch is changing
state.
b
OTHER_UNIT_STANDBY
= The other unit (in a 1:1 system) is in standby, or there is a
problem reading the switch position, or the switch is changing
state.
b
ANTENNA
= RF output is directed to the Antenna; or there is a problem
with the Ant/DL switch (if b
DUMMY_LOAD
is also set).
b
DUMMY_LOAD
= RF output is directed to the Dummy Load; or there is a
problem with the Ant/DL switch (if b
ANTENNA
is also set).
Previously, the summary warning flag indicated that any warning was Active. The distinction between Active
and Latched was meaningless, because all warnings in firmware versions prior to 2.50 were not latched. New
warnings added in version 2.50 will be latched, so the flag will report when any warning is Latched. If a Non-
Latched warning occurs, such as LOCAL MODE WARNING, the b
LSUM_ANY_WARNING
flag will be set while the
warning is active, and will be clear when the user exits LOCAL mode. If a Latched warning occurs (such as
FAN FAILURE) the flag will be set until faults are reset.
For both the THIS_UNIT and the OTHER_UNIT ONLINE/STANDBY flag pairs, if there is a problem reading
the 1:1 switch, or if the switch is being changed, both ONLINE and STAND-BY flags will be set. If the switch
is not connected, both will be clear. (Under normal conditions, only one flag of each pair would be set, and
the other would be clear.)
For the ANTENNA and DUMMY_LOAD flag pair, if there is a problem reading the Ant/DL switch, or if the
switch is being changed, both flags will be set. If the switch option is not installed, both will be clear.
Otherwise, the flag that is set indicates the switch position.
4 Faults and Alarms
One of the major functions of the serial I/O port is the reporting of problems to the host controller. A problem
is referred to as a fault, and any fault will generate an alarm. These two terms (fault and alarm) are often used
interchangeably.
4.1 Reporting of Faults
If a fault condition is detected by the SSPA, the following actions are taken:
 The bit corresponding to the detected condition is set in the Latched Fault Mask.
 The same bit is set in the Active Fault Mask.
 The service request relay contact is closed (if the Serial I/O port relay is programmed for “Service
Request”; see Section 4.3).
The host can detect the fault either by monitoring the service request relay contact, or by polling the unit using
the Get Faults message (see section 3.3). The host computer can clear the service request relay contact by
issuing a Clear Service Request command (see section 3.4). This contact will not close again unless another
fault condition occurs. This command does not disturb the state of any other fault indicators.
When the fault condition clears, either because it has been repaired or it went away by itself, the following
actions are taken:
 The Active Fault Mask bit corresponding to the condition is cleared.
 If the fault is of a non-latched type, the same bit in the Latched Fault Mask is cleared.
 If all faults in the Latched Fault Mask are cleared, the service request relay contacts are cleared.