Released
PMC-Sierra, Inc.
PM9311/2/3/5 ETT1™ CHIP SET
Data Sheet
PMC-2000164
ISSUE 3
ENHANCED TT1™ SWITCH FABRIC
Table 3. LCS Format from Linecard to Switch
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Req
Valid
Label_1 [13:7]
Byte 0
Byte 1
Byte 2
Byte 3
Byte 4
Byte 5
Byte 6
Byte 7
Label_1 [6:0]
Type_1
[3]
Request
Field
Type_1 [2:0]
Rsvd
Rsvd
Payload
Valid
Seq_Number[9:3]
Payload
Field
Seq_Number[2:0]
Payload_Hole_Request[3:0]
Rsvd
Hole Field
CRC Field
CRC-16[15:8]
CRC-16 [7:0]
Payload Data
Bytes 8-71 or
8-83
Payload
Table 4. Definitions of LCS Fields from Linecard to Switch
Field
Size (bits)
Definition
Req Valid
Label_1
1
14
4
Indicates that request field is valid (Request Label_1).
Label that is being requested (e.g. unicast-QID/multicast-label/TDM-label).
Segment type that is being requested (e.g. Control Packet).
Indicates that the Payload Data field contains a valid payload.
A sequence number for synchronizing grants with payloads.
Type_1
Payload Valid
Seq_Number
1
10
4
Payload_Hole_
Request
Request for a “hole” in the payload stream from switch to linecard. (Priority 3,2,1,0 for bits
[3:0], respectively.) (See Section 1.2.4 “End-to-End Flow Control” on page 22 for
explanation).
a
CRC-16
16
16-bit CRC calculated over complete 64-bit prepend.
Payload Data
64 or 76
bytes
Payload Data
a. See Section 1.6.4.1 “Use of CRC-16 Field” on page 73 for details of CRC calculation and Section 3.4.2.2 “Reset and
Control” on page 169, bit 4.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
65
PMC [ PMC-SIERRA, INC ]
