Paradise Datacom 4 RU Chassis, Руководство по эксплуатации

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4 RU SSPA Chassis Operations Manual 201627 REV X 83
7.2.2 Data Packet
The data sub-packet is comprised of 6 to 32 bytes of information. It is further divided
into seven (7) fields as shown in
Figure 7-6
. The first six (6) fields comprise the com-
mand preamble while the last field is the actual data.
7.2.2.1 Protocol ID
This field provides backward compatibility with older generation equipment protocol. It
should normally be set to zero (0). This field allows the amplifier to auto-detect other
firmware versions.
7.2.2.2 Request ID
This is an application specific field. The amplifier will echo this byte back in the re-
sponse frame without change. This byte serves as a request tracking feature.
7.2.2.3 Command
This one byte field tells the receiver how to use the attached data. There are only four
(4) possible values for this field. The sender and receiver are limited to two commands.
For example: if the sender issued “Set Request” command, receiver must answer with
“Get Request” and “Get Response” form of the command. The byte value for each
command is given in
Table 7-1
.
HEADER
(4 bytes)
DATA
(6-32 bytes)
TRAILER
(1 byte)
DATA FIELD
Protocol ID
1 Byte
Request ID
1 Byte
Command
1 Byte
Data Tag
1 Byte
Error Status /
Data Address
1 Byte
Data Length
1 Byte
Command Data
Sub Structure
0 - 26 Bytes
COMMAND PREAMBLE
Figure 7-6: Data Sub-Packet
Command Name Command Byte Value
Set Request 0
Get Request 1
Set Response 2
Get Response 3
Table 7-1: Command Byte Values