DT-4500 Series C- and Ku-Band Down Converters
MN/DT4500.IOM
Serial Interface Operation
Revision 2
8–3
username (default: comtech) and the password (default: comtech), the Telnet
server accepts the same operands used by the serial remote interface.
8.3
Access Methods
You may access a converter directly by using a physical address, or indirectly
through a backup converter by using a virtual address.
8.3.1
Direct (Physical) Access
You may directly access a converter via the EIA-232 interface, or the EIA-485
interface in a bus configuration.
In this control network, all converters including the backup converter are
paralleled on a common EIA-485 cable. Both up- and down converters can be
mixed on the cable as long as each converter has a unique physical address. Only
one EIA-485 port is required on the system's M&C PC. If you directly execute a
configuration change to a converter in a redundant system, the backup
converter detects the change via the High Speed Bus and updates its backup
tables.
For EIA-232 control, a direct EIA-232 cable connection is required for each
accessible converter. When using an external M&C PC, one EIA-232 port per
converter is required. This mode is commonly used with an ASCII terminal for
bench testing.
8.3.2
Indirect (Virtual) Access
You may indirectly address a converter in Redundancy Mode by adding a virtual
address to the backup converter's physical address. The virtual address
corresponds to the converter's position in the redundant subsystem. The backup
converter recognizes the virtual address and executes the command via the High
Speed Bus.
For control via the EIA-485 interface, you must use a common EIA-485 bus cable
to connect one or more backup converters to the system's M&C PC or ASCII
terminal. Only one EIA-485 port is required on the M&C PC. The backup
