Comtech EF Data DT-4500-A Series - Manual (Page 114)

DT-4500-A Series Downconverters Revision 1
Appendix A MN-DT4500A
A–4
Example: 10V3 (Addresses the third converter controlled by the backup converter whose
physical address is 10.)
A.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.
A.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.
A.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.
A.5.2 Baud Rate
The supported baud rates are 1200, 2400, 4800, 9600 (default), 19200, and 38400 baud.
A.5.3 Asynchronous Character Format
The asynchronous character format is 8-N-1 (i.e., 8 data bits; no parity; 1 stop bit).
A.5.4 Character Set
The command syntax uses the printable ASCII character set.