CYNCP80192 Cypress Semiconductor, CYNCP80192 Datasheet - Page 17

• Manufacturer Part Number: CYNCP80192
• Description: Network Database Coprocessor
• Manufacturer: Cypress Semiconductor

SSRAM Address Prefix. In the implementation with a SSRAM connected to the NSE (see Figure 13-1), these three bits are used
as an SSRAM address prefix (SAP) to generate the address of the associative SSRAM. (Refer to the data sheet specifications
of the CYNSE70XXX devices for further information.)
Start. When the command and associated parameters have been written to the command descriptor, a process running on the
network processor can set this bit to initiate the operation by the CYNPC80192.
Search Size. This two-bit field is used only by Search and Learn instructions and describes the word size for these operations.
Note. Learn command is not supported in the 272-bit wide table. The following describes the data that will be presented to the
NSE for various search sizes.
Note. The two-bit search size must contain 00 for non-Search/Learn instructions.
Access Location. This two-bit field is used by Read, Write, Move, and Swap instructions, and indicates the region accessed in
the NSEs or the associative data SSRAMs.
Direct/Indirect. This one-bit field is used by Read and Write instructions and controls the address generation to the NSEs and
the associated data SSRAMs. When this bit is set, it specifies indirect addressing using SSRs in the NSEs. (Refer to the
specifications of CYNSE70XXX for further information.)
Layer Attribute and Valid Bit for Data 0. This field contains the three-bit layer attribute as well as a valid bit to accompany data
in the Data 0, in the context descriptor. The layer attributes bits may be used for maintaining multiple search tables (of different
widths) in the NSE(s). However, if multiple search tables are not used, these bits can be used for any purpose.
Layer Attribute and Valid Bit for Data 1. This field contains a three-bit layer attribute as well as a valid bit to accompany data
in the Data 1, in the context descriptor. The layer attributes bits may be used for maintaining multiple search tables (of different
widths) in the NSE(s). However, if multiple search tables are not used, these bits can be used for any purpose.
Layer Attribute and Valid Bit for Data 2. This field contains the three-bit layer attribute as well as a valid bit to accompany data
in the Data 2, in the context descriptor. The layer attributes bits may be used for maintaining multiple search tables (of different
widths) in the NSE(s). However, if multiple search tables are not used, these bits can be used for any purpose.
Layer Attribute and Valid Bit for Data 3. This field contains the three-bit layer attribute as well as valid bit to accompany data
in the Data 3, in the context descriptor. The layer attributes bits may be used for maintaining multiple search tables (of different
widths) in the NSE(s). However, if multiple search tables are not used, these bits can be used for any purpose.
Commands. NDC currently supports six basic commands. Command bits 7 through 3 are reserved and must be programmed
as 0s for the following commands:
7.3.1
Read Command (00 H). Table 7-4 shows the format for the Read command. The Read command’s structure is rd(ADR). The
Read command uses two 64-bit words in the context descriptor, command descriptor word, and Data 0 word. The Read command
is issued through the command descriptor. The Read access location, either data array, mask array, NSE register, or external
SSRAM is encoded in the command descriptor word. Bits 15–0 of the Data 0 word contain the Read address. Bits 23–19 of the
Data 0 word supply the NSE ID (SEID).
Document #: 38-02043 Rev. *B
000: ×68 ({Data 0, layer attribute/valid bit for Data 0})
001: ×136 ({Data 1, layer attribute/valid bit for Data 1; Data 0, layer attribute/valid bit for Data 0})
010: ×272 ({Data 3, layer attribute/valid bit for Data 3; Data 2, layer attribute/valid bit for Data 2;
Data 1, layer attribute/valid bit for Data 1; Data 0, layer attribute/valid bit for Data 0}.
000: NSE data array.
001: NSE mask array.
010: SRAM connected to the NSE.
011: NSE internal registers.
000: Read
001: Write
010: Search
011: Learn
100: Move
101: Swap.
Command Description and Parameters
CYNCP80192
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