CYNSE70256-66BHC Cypress Semiconductor Corp, CYNSE70256-66BHC Datasheet - Page 14

• 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

7.2
The device contains two banks of 32 72-bit GMRs (sixteen pairs) dynamically selected in every Search operation to select the
Search subfield. The addressing of these registers is explained in Figure 7-2. The 4-bit GMR index supplied on the command
bus can apply sixteen pairs of global masks during Search and Write operations, as shown below.
Each mask bit in the GMRs is used during Search and Write operations. In Search operations, setting the mask bit to 1 enables
compares; setting the mask bit to 0 disables compares at the corresponding bit position (forced match). In Write operations to
the data or mask array, setting the mask bit to 1 enables Writes; setting the mask bit to 0 disables Writes at the corresponding
bit position.
7.3
The device contains two banks of eight search successful registers (SSRs) to hold the index of the location at which a successful
search occurred. The format of each register is described in Table 7-2. The Search command specifies which SSR stores the
index of a specific Search command in cycle B of the Search instruction. Subsequently, the host ASIC can use this register to
access that data array, mask array, or external SRAM using the index as part of the indirect access address (see Table 10-3 and
Table 10-6).
The device with a valid bit set performs a Read or Write operation. All other devices suppress the operation.
Note:
Document #: 38-02035 Rev. *E
6.
In 72-bit Search and Write operations, the host ASIC must program both the even and odd mask registers with the same values for each of the banks.
Mask Registers
Search Successful Registers (SSR[0:7])
Figure 7-1. Comparand Register Selection during Search and Learn Instructions
Search and Write Command Global Mask Selection
Figure 7-2. Addressing the GMR Array
Address
index
Index 143
10
12
13
14
15
15
11
0
1
0
1
2
3
4
5
6
7
8
9
143
72
30
0
2
4
6
10
12
14
16
18
20
22
24
26
28
30
72
0
2
4
6
8
72
31
1
3
5
7
72
13
15
17
19
21
23
25
27
29
31
0
11
1
3
5
7
9
0
[6]
CYNSE70256
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