CYNSE70256-66BHC Cypress Semiconductor Corp, CYNSE70256-66BHC Datasheet - Page 65

• Manufacturer Part Number: CYNSE70256-66BHC
• Manufacturer: Cypress Semiconductor Corp

Specifications of CYNSE70256-66BHC

• Operating Temp Range: 0C to 70C
• Operating Temperature Classification: Commercial
• Package Type: BGA
• Mounting: Surface Mount
• Lead Free Status / Rohs Status: Not Compliant

The following is the sequence of operation for a single 288-bit Search command (see also Subsection 10.2, “Commands and
Command Parameters,” on page 19).
The logical 288-bit Search operation is shown in Figure 10-47. The entire table of 288-bit entries is compared to a 288-bit word
K that is presented on the DQ bus in cycles A, B, C, and D of the command using the GMR and the local mask bits. The GMR is
the 288-bit word specified by the two pairs of GMRs selected by the GMR indexes in command cycles A and C in each of the
four devices. The 288-bit word K that is presented on the DQ bus in cycles A, B, C, and D of the command is compared to each
entry in the table starting at location 0. The first matching entry’s location address L is the winning address that is driven as part
of the SRAM address on the SADR[23:0] lines (Section 12.0, “SRAM Addressing,” on page 86).
Notes:
Document #: 38-02035 Rev. *E
CFG = 0101010101010101, HLAT = 010, TLSZ = 01, LRAM = 0, LDEV = 0.
Note: |(LHI[6:0]) stands for the boolean ‘OR’ of the entire bus LHI[6:0].
Note: |LHO[1:0] is logical “or” of LHO[0] and LHO[1].
21. CMD[2] = 1 signals that the Search is a 288-bit search. CMD[8:3] in this cycle is ignored.
22. For 288-bit searches, the host ASIC must supply four distinct 72-bit data words on DQ[71:0] during cycles A, B, C, and D. The GMR index in cycle A selects a
• Cycle A: The host ASIC drives CMDV HIGH and applies Search command code (10) on CMD[1:0] signals. {CMD[10],CMD[5:3]}
• Cycle B: The host ASIC continues to drive CMDV HIGH and applies Search command code (10) on CMD[1:0]. The DQ[71:0]
• Cycle C: The host ASIC drives CMDV HIGH and applies Search command code (10) on CMD[1:0] signals. {CMD[10],CMD[5:3]}
• Cycle D: The host ASIC continues to drive CMDV HIGH and applies Search command code (10) on CMD[1:0]. CMD[8:6]
signals must be driven with the index to the GMR pair used for bits [287:144] of the data being searched in this operation.
DQ[71:0] must be driven with the 72-bit data ([287:216]) to be compared against all locations 0 in the four-word 72-bit page.
The CMD[2] signal must be driven to logic 1.
is driven with the 72-bit data ([215:144]) to be compared against all locations 1 in the four 72-bits-word pages.
signals must be driven with the index to the GMR pair used for bits [143:0] of the data being searched. CMD[8:6] signals must
be driven with the bits that will be driven on SADR[23:21] by this device if it has a hit. DQ[71:0] must be driven with the 72-bit
data ([143:72]) to be compared against all locations 2 in the four 72-bits-word page. The CMD[2] signal must be driven to logic 0.
signals must be driven with the index of the SSR that will be used for storing the address of the matching entry and the hit flag
(see page 14 for the description of SSR[0:7]). The DQ[71:0] is driven with the 72-bit data ([71:0]) to be compared to all locations
3 in the four 72-bits-word pages. CMD[5:2] is ignored because the Learn instruction is not supported for ×288 tables.
pair of GMRs in each of the banks of each of the four devices that apply to DQ data in cycles A and B. The GMR index in cycle C selects a pair of GMRs in each
of the banks of each of the four devices that apply to DQ data in cycles C and D.
SADR[23:0]
CMD[10:2]
|(LHI[6:0])
|LHO[1:0]
CMD[1:0]
CMD[2]
CLK2X
PHS_L
ALE_L
CMDV
WE_L
OE_L
CE_L
SSV
SSF
Figure 10-46. Timing Diagram for 288-bit Search Device Number 3 (Last Device)
DQ
0
0
0
0
0
1
cycle
A B A B A B A B
A B C D A B C D
1
Search1
cycle
01
D1
[21]
2
cycle
3
Search2
D2
cycle
01
4
cycle
A B A B
A B C D
5
Search3
D3
cycle
01
6
1
cycle
Search1
(Miss on
this device.)
7
z
z
z
z
z
cycle
8
0
0
Search2
(Miss on
this device.)
cycle
9
z
z
z
z
z
cycle
10
[23]
1
0
0
0
0
Search3
(Global miss.)
1
CYNSE70256
0
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