ICS ELECTRONICS 4863 Manual page 111

3.9.4
When no Network protocol is selected (SYST:COMM:SER:NET OFF),
the RS-485 interface operates like the RS-232 interface does with echo off.
See the examples in paragraphs 3.9.2 and 3.9.3.
3.9.5 Addressed Network Protocol
The 2363 supports a multi-device or multidrop network connections when
the NETwork Address mode is selected. When Address is selected, the
2363 recognizes commands addressed to it by checking the first two
characters of the message for the correct address sequence. The first
character must be the STX character. The second character must be the
address character (0-9 and :;<=>?). All responses are the same as for normal
3
RS-232 and RS-485 operation. The Address command message format is
e.g. The IDN query example becomes:
3.9.6
Network messages can be made more secure by enclosing the commands
in a packet that is protected with a checksum. When Packet Protocol is
selected, the 2363 recognizes commands addressed to it by checking the
first two characters of the packet message for the correct address sequence
as described in 3.9.5. The Packet is then checksumed and the result
compared against the checksum at the end of the packet. If the checksum
matches, the command is parsed and executed (assuming it is a valid
command). If the checksum does not match, a NAK response packet is sent
to the controller.
RS-485 Protocol
STX Addr Message LF
STX 4 *IDN? LF
ICS Electronics, 2363, S/N 910123, Rev. X1.X0 LF
> LF
Packet Protocol
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