Comtech EF Data DT-4500 Series, Инструкция по установке и эксплуатации

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DT-4500 Series C- and Ku-Band Down Converters MN/DT4500.IOM
Serial Interface Operation Revision 2
8–5
8.4.3 IP Address
The IP address is a unique address on a network that supports Internet Protocol
(i.e., IPv4). An example of a network address using IPv4 is 192.168.1.4 (factory
default IP address). This value must be configured correctly to allow a Telnet
session to control the unit.
8.5 Basic Protocol
Whether in EIA-232 or EIA-485 mode, all data is transmitted as asynchronous
serial characters, suitable for transmission and reception by a UART.
All data is transmitted in framed packets. The Controller is assumed to be a PC or
ASCII dumb terminal that is in charge of the process of monitor and control. The
Controller is the only device that is permitted to initiate, at will, the transmission
of data. Targets are only permitted to transmit when they have been specifically
instructed to do so by the Controller.
All bytes within a packet are printable ASCII characters, less than ASCII code 127.
In this context, the Carriage Return and Line Feed characters are considered
printable.
All messages from Controller-to-Target require a response, with one exception: This
will be either to return data that has been requested by the Controller, or to
acknowledge reception of an instruction to change the configuration of the Target.
The exception to this is when the Controller broadcasts a message (such as Set
Time/Date) using Address 0, when the Target is set to EIA-485 mode.
8.5.1 Transmission Mode
The transmission mode is half duplex implemented in Command/Response
convention. This method requires the external system monitor and control unit
to initiate all communications by command and all converters to respond with
either confirmation or an error message. The confirmation may contain status
information.