Cypress CY7C1550V18 Manual De Usuario
CY7C1546V18, CY7C1557V18
CY7C1548V18, CY7C1550V18
CY7C1548V18, CY7C1550V18
Document Number: 001-06550 Rev. *E
Page 24 of 28
Switching Waveforms
Read/Write/Deselect Sequence
Figure 5. Waveform for 2.0 Cycle Read Latency
DON’T CARE
UNDEFINED
1
2
3
4
5
6
7
8
9
10
READ
READ
READ
NOP
WRITE
WRITE
t
NOP
11
K
K
LD
R/W
A
tKH tKL
tCYC
tHC
tSA tHA
SC
A0
A1
A2
A3
A4
CQ
CQ
QVLD
QVLD
t
NOP
t
QVLD
t
tCCQO
tCQOH
t
tCQOH
QVLD
t
NOP
DQ
KHKH
12
(Read Latency = 2.0 Cycles)
NOP
NOP
CCQO
tSD
HD
tSD
tHD
t
CLZ
tCHZ
D20 D21
D30
D31
t
CQDOH
Q00
Q11
Q01 Q10
tDOH
tCO
Q40 Q41
tCQD
t
t
tCQH
CQHCQH
Notes
29. Q00 refers to output from address A0. Q01 refers to output from the next internal burst address following A0, that is, A0 + 1.
30. Outputs are disabled (High-Z) one clock cycle after a NOP.
31. The third NOP cycle between read to write transition is not necessary for correct device operation when Read Latency = 2.0 cycles; however at high frequency operation,
30. Outputs are disabled (High-Z) one clock cycle after a NOP.
31. The third NOP cycle between read to write transition is not necessary for correct device operation when Read Latency = 2.0 cycles; however at high frequency operation,
it is required to avoid bus contention.
32. In this example, if address A4 = A3, then data Q40 = D30 and Q41 = D31. Write data is forwarded immediately as read results. This note applies to the whole diagram.