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CY7C024/0241
CY7C025/0251
Document #: 38-06035 Rev. *B
Page 9 of 20
Switching Waveforms
Notes:
19. R/W is HIGH for read cycles
20. Device is continuously selected CE = VIL and UB or LB = VIL. This waveform cannot be used for semaphore reads.
21. OE = VIL.
22. Address valid prior to or coincident with CE transition LOW.
23. To access RAM, CE = VIL, UB or LB = VIL, SEM = VIH. To access semaphore, CE = VIH, SEM = VIL.
tRC
tAA
tOHA
DATA VALID
PREVIOUS DATA VALID
DATA OUT
ADDRESS
7C024–14
tOHA
Read Cycle No. 1 (Either Port Address Access)[19, 20, 21]
tACE
tLZOE
tDOE
tHZOE
tHZCE
DATA VALID
tLZCE
tPU
tPD
7C024–15
ISB
ICC
DATA OUT
OE
CE and
LB or UB
CURRENT
Read Cycle No. 2 (Either Port CE/OE Access)[19, 22, 23]
UB or LB
DATA OUT
7C024–16
tRC
ADDRESS
tAA
tOHA
CE
tLZCE
tABE
tHZCE
tHZCE
tACE
tLZCE
Read Cycle No. 3 (Either Port)[19, 21, 22, 22, 23]