8.1.1.3 Source Address
The source address specifies the address of the node that is sending the packet. All unique addresses, except the broadcast address, are equal and can be assigned to individual units. The host computer must also have a unique network address.
8.1.2 Data Packet
The data
HEADER (4 bytes)
DATA
TRAILER
(1 byte)
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Protocol ID | Request ID | Command | Data Tag | Error Status / | Data Length | Command Data | |
Data Address | Sub Structure | ||||||
1 Byte | 1 Byte | 1 Byte | 1 Byte | 1 Byte | |||
1 Byte | 0 - 26 Bytes | ||||||
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Figure 8-4: Data Sub-Packet
8.1.2.1 Protocol ID
This field provides backward compatibility with older generation equipment protocol. It should normally be set to zero. This field allows the unit to
8.1.2.2 Request ID
This is an application specific field. The amplifier will echo this byte back in the response frame without change. This byte serves as a request tracking feature.
8.1.2.3 Command
The SSPA protocol is a table based protocol. It allows the user to view and modify data tables located on the controlled device. Throughout the remainder of this description, “sender” will refer to the host PC, and “receiver” will refer to the SSPA unit.
Sender and receiver are limited to two commands and two command responses. The Get Request command issued by a command sender allows monitoring of existing conditions and parameters on the receiver. The Get Request frame should not have any bytes in the Data Filed and be no longer than 11 bytes.
The Response frame from the receiver will contain a Get Response designator in the Command field. If the receiver does not detect any errors in the Get Request frame, the requested data will be attached to the response frame. The length of the Get Response frame
62 | 208143 REV - | Operations Manual, HPA3, Mini Compact Outdoor SSPA |
