Seagate Kinetic HDD Product Manual, Rev. B
22
5.2
K
INETIC
P
ROTOCOL
D
ATA
U
NIT
A Kinetic PDU is composed of five fields
1. PDU version
2. Kinetic Message length
3. value length
4. Kinetic Message
5. Value
Some PDUs have a null value. It is important to note that the value is not encoded in the Kinetic Message; it is a separate
field of the Kinetic PDU.
Specifically, a Kinetic PDU structure is shown in Table 5.2.1.
Table 13: Kinetic PDU Structure
Figure 5.2.1 shows a visual of how the Kinetic PDU is structured.
Figure 7 Kinetic Protocol Data Unit Message Packet
Starting Offset
Type
Length
Description
0
Byte
1 Byte
PDU version:
currently hex 46, denoting the beginning of the message.
1
4-byte Big
Endian Integer
4 Bytes
The number of bytes in the Kinetic Message field.
The maximum length for a Kinetic Message is 1 MiB
(2^20 bytes).
5
4-byte Big
Endian Integer
4 Bytes
The number of bytes in the value field.
The maximum length for a value is 1 MiB (2^20 bytes).
9
Bytes
<= 1 MiB
The Kinetic Message.
9 + length of
Kinetic Message
Bytes
<= 1 MiB
The value.
