Altera SerialLite II Protocol - Manual (Page 39)

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SerialLite II Protocol Reference Manual
SerialLite II Specification
Figure 2–18. Link Management Packet Encapsulation
Link Management Packet Size
The link management packet has a fixed length of four bytes: a single byte
identifier followed by three bytes of payload.
Link Management Packet Payload Format
Table 2–18 shows the link management packet payload format using the
following parameters:
■ FC_TIME = Flow control time
■ ACK = Acknowledgement
■ NACK = Negative acknowledgement
■ SID = Segment identification
■ BIP-8 = 8 bits of bit interleaved parity
■ CLASS = Packet type class
Link Management Packet Type (LMP[23:20])
SerialLite II currently has the following management packets defined:
■ Flow Control Packets (Link Packet Type = 0x1); see detailed
description in
“Flow Control (Optional)” on page 2–61 .
■ Retry-on-Error Control Packets (Link Packet Type = 0x2); see
detailed description in
“Retry-on-Error (Optional)” on page 2–64 .
Link Management Packet Parameter (LMP[19:8])
This field contains parameters specific to the type of link management
packet. See
“Flow Control (Optional)” on page 2–61 and “Retry-on-Error
(Optional)” on page 2–64 for details.
SLP Link Management Packet Payload
Table 2–18. Link Management Packet Format
Bits
[23:20] [19:16] [15:12] [11:8] [7:4] [3:0]
Type Parameter Description Protection
Flow control packet 0x1 CLASS FC_TIME BIP-8
Retry-on-error control packet 0x2 CLASS 0x0 SID BIP-8