User's Manual Part 3

Backplane/Interface Boards - 129 -
Affinity
®
LBD-200C-N1 Transmitter
Product Manual
frozen by the main firmware thus minimizing disturbance to the transmitter. When the input is
reapplied, the tracking resumes.
PAS Manager Support
In the Power Amplifier Segment (PAS) quad system, the MSI monitors two signals,
PAS_fault
and
PAS_presence, for each PAS. The monitoring is performed in the Main CPLD in a system
called the PAS Manager. The failed PAS is detected by the MSI main firmware by reading the
registers in the Main CPLD.
The MSI main firmware uses a calibration variable
QUAD_MASK to inform the MSI CPLD of the
number of installed PAS modules. This is necessary to set the proper ALC reduction for the
given number of PAS.
Auxiliary Port Management
The MSI Auxiliary Serial Port (aux port) is used to monitor and control a device connected to the
Affinity® transmitter, such as a modulator. The Port MCU handles port management; however,
the commands and requests for status of the modulator originate in the top-level management
system and pass through the Main MCU as TNET serial messages. The Main MCU copies the
command or status request from the TNET message and passes the request to the Port CPLD,
which sends the appropriate control or monitoring message to the managed port device.
Refer to SNMP document for a list and description of the variables managed in the auxiliary
equipment connected to the Auxiliary Port.
Port MCU Firmware
The Port MCU is dedicated solely to the management of a device connected to the Auxiliary
Serial Port. Equipment such as a modulator may be connected to the aux port. In the factory,
the firmware program appropriate to the end-user’s purchased equipment is loaded in the Port
MCU.
The Port MCU periodically reads fault alarms for various modulator systems from the modulator
and writes the conditions of the systems (pass/fail) to the Port CPLD. The alarm status is
available to the Main MCU for fault notification to the top-level management system.
At any time, the top-level management system can issue a command to the modulator. The
command is received by the Main MCU and passed through the Port CPLD to the Port MCU.
The Port MCU develops the corresponding message with arguments given in the original
command, and sends messages to the modulator connected to the aux port.