Paradise Datacom 4 RU Chassis, Руководство по эксплуатации

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94 201627 REV X 4 RU SSPA Chassis Operations Manual
7.4 Example 1 Check SSPA settings
Assumptions:
unit unique network address - 5;
PC Host unique network address - 10;
Request ID - 111;
Unit attached to the serial line;
PC request string:
Byte
Count
Bytes Description
1 170 Frame Sync Byte 1
2 85 Frame Sync Byte 2
3 5 Destination Address of Unit
4 10 Source Address of Request Originating PC Host
5 0 Protocol Version Compatibility. Field must always be “0”.
6 111
Request ID byte is set by originator, will be echoed back by
respondent.
7 1 Command field for “Get” type of the request
8 0
“System Settings” tag indicates which data from respondent
required in response frame
9 1
Data Address field indicates the beginning data address inside
of the “System Settiongs” data set to 1 (first element)
10 28
Data Length field indicates how many data bytes of the
“System Settings” requested from the unit
11 156 Arithmetic checksum of bytes number 3 through 10