Cypress CY7C0837AV Manual De Usuario
CY7C0837AV, CY7C0830AV
CY7C0831AV, CY7C0832AV
CY7C0831AV, CY7C0832AV
CY7C0832BV, CY7C0833AV
Document #: 38-06059 Rev. *S
Page 17 of 28
Figure 10. Bank Select Read
Figure 11. Read-to-Write-to-Read (OE = LOW)
Switching Waveforms
(continued)
Q
3
Q
1
Q
0
Q
2
A
0
A
1
A
2
A
3
A
4
A
5
Q
4
A
0
A
1
A
2
A
3
A
4
A
5
t
SA
t
HA
t
SC
t
HC
t
SA
t
HA
t
SC
t
HC
t
SC
t
HC
t
SC
t
HC
t
CKHZ
t
DC
t
DC
t
CD2
t
CKLZ
t
CD2
t
CD2
t
CKHZ
t
CKLZ
t
CD2
t
CKHZ
t
CKLZ
t
CD2
t
CH2
t
CL2
t
CYC2
CLK
ADDRESS
(B1)
CE
(B1)
DATA
OUT(B2)
DATA
OUT(B1)
ADDRESS
(B2)
CE
(B2)
t
CYC2
t
CL2
t
CH2
t
HC
t
SC
t
HW
t
SW
t
HA
t
SA
t
HW
t
SW
t
CD2
t
CKHZ
t
SD
t
HD
t
CKLZ
t
CD2
NO OPERATION
WRITE
READ
READ
CLK
CE
R/W
ADDRESS
DATA
IN
DATA
OUT
A
n
A
n+1
A
n+2
A
n+2
D
n+2
A
n+3
A
n+4
Q
n
Q
n+3
Notes
34. In this depth-expansion example, B1 represents Bank #1 and B2 is Bank #2; each bank consists of one Cypress FLEx18 device from this data sheet. ADDRESS
(B1)
= ADDRESS
(B2)
.
35. ADS = CNTEN= BE0 – BE1 = OE = LOW; MRST = CNTRST = CNT/MSK = HIGH.
36. Output state (HIGH, LOW, or high-impedance) is determined by the previous cycle control signals.
37. During “No Operation,” data in memory at the selected address may be corrupted and should be rewritten to ensure data integrity.
38. CE
36. Output state (HIGH, LOW, or high-impedance) is determined by the previous cycle control signals.
37. During “No Operation,” data in memory at the selected address may be corrupted and should be rewritten to ensure data integrity.
38. CE
0
= OE = BE0 – BE1 = LOW; CE
1
= R/W = CNTRST = MRST = HIGH.
39. CE
0
= BE0 – BE1 = R/W = LOW; CE
1
= CNTRST = MRST = CNT/MSK = HIGH. When R/W first switches low, because OE = LOW, the Write operation cannot be
completed (labelled as no operation). One clock cycle is required to three-state the I/O for the Write operation on the next rising edge of CLK.