Basic Protocol; Packet Structure - Comtech EF Data LPOD Series Installation And Operation Manual

5.3.4 Basic Protocol

All data is transmitted in framed packets. The host controller is assumed to be a PC or ASCII dumb terminal, which 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.

5.3.5 Packet Structure

Start of Packet Target Address
<
ASCII code 60 ASCII codes 48-57
(1 character) (4 characters)
Controller-to-Target examples:
Serial Interface Operation
Address Delimiter
0-9 /
ASCII code 47 ASCII codes 65-90, 97-122
(1 character)
(COMMAND) <0135/MUT=1{CR}
(QUERY) <0135/MUT?{CR}
Low Power Outdoor (LPOD) Amplifier/Block Up Converter (BUC)
Controller-to-Target
Instruction Code Code Qualifier
A-Z, a-z = or ?
ASCII codes
(3 characters) 61 or 63
(1 character)
5–6
Revision 15
Optional
End of Packet
Arguments
Carriage Return {CR}
ASCII code 13
(n characters) (1 character)
MN-LPOD