CYNSE70032
Document #: 38-02042 Rev. *E
Page 15 of 126
9.0
Information Register
Table 9-1 describes the information register fields.
TLSZ
[3:2]
01
Table Size. The host ASIC must program this field to configure the chips into a table of
a certain size. This field affects the pipeline latency of the Search and Learn operations
as well as the Read and Write accesses to the SRAM (SADR[21:0], CE_L, OE_L, WE_L,
ALE_L, SSV, SSF, and ACK). Once programmed, the Search latency stays constant.
The latency by number of CLK cycles is as follows:
00: One device
4
01: Up to eight devices 5
10: Up to 31 devices
6
11: Reserved.
HLAT
[6:4]
000
Latency of Hit Signals. This field further adds latency to the SSF and SSV signals by
the following number of CLK cycles during searches and ACKs in an SRAM Read access:
000: 0
100: 4
001: 1
101: 5
010: 2
110: 6
011: 3
111: 7.
LDEV
[7]
0
Last Device in the Cascade. When set, this is the last device in the depth-cascaded
table and is the default driver for the SSF and SSV signals. In the event of a Search failure,
the device with this bit set drives the hit signals as follows: SSF = 0, SSV = 1.
During nonSearch cycles, the device with this bit set drives the signals as follows:
SSF = 0, SSV = 0.
LRAM
[8]
0
Last Device on the SRAM Bus. When set, this device is the last device on the SRAM
bus in the depth-cascaded table and is the default driver for the SADR, CE_L, WE_L, and
ALE_L signals. In cycles where no CYNSE70032 device (in a depth-cascaded table)
drives these signals, the signals are driven as follows: SADR = 22’h3FFFFF, CE_L = 1,
WE_L = 1, and ALE_L = 1. OE_L is always driven by the device for which this bit is set.
CFG
[16:9]
00000000
Database Configuration. The device is divided internally into four partitions of 8K × 68
bits, each of which can be configured as 8K × 68 bits, 4K × 136 bits, or 2K × 272 bits, as
follows:
00: 4K × 68 bits
01: 2K × 136 bits
10: 1K × 272 bits
11: Reserved.
Bits[10:9] apply to configuring the first partition in the address space.
Bits[12:11] apply to configuring the second partition in the address space.
Bits[14:13] apply to configuring the third partition in the address space.
Bits[16:15] apply to configuring the fourth partition in the address space.
[67:17]
0
Reserved.
Table 9-1. Information Register Description
Field
Range
Initial Value
Description
Revision
[3:0]
0001
Revision Number. This is the current device revision number. Numbers
start at one and increment by one for each revision of the device.
Implementation
[6:4]
000
This is the device implementation number.
Reserved
[7]
0
Reserved.
Device ID
[11:8]
0001
This is the device identification number.
Device ID
[12]
0 or 1
Reserved.
Device ID
[15:13]
000
These are the three most significant bits of the device identification
number.
MFID
[31:16]
1101_1100_0111_1111
Manufacturer ID. This field is the same as the manufacturer identifi-
cation number and continuation bits in the TAP controller.
Reserved
[67:32]
Reserved.
Table 8-1. Command Register Description (continued)
Field
Range
Initial Value
Description