Rainbow Electronics AT45DB642 - Manual (Page 20)

20
AT45DB642
1638F–DFLSH–09/02
Read Operations
The following block diagram and waveforms illustrate the various read sequences available.
Main Memory Page Read
Main Memory Page to Buffer Transfer (Data from Flash Page Read into Buffer)
Buffer Read
FLASH MEMORY ARRAY
PAGE (1056 BYTES)
BUFFER 2 (1056 BYTES) BUFFER 1 (1056 BYTES)
I/O INTERFACE
MAIN MEMORY
PAGE TO
BUFFER 1
MAIN MEMORY
PAGE TO
BUFFER 2
MAIN MEMORY
PAGE READ BUFFER 1
READ
BUFFER 2
READ
SO I/O7 - I/O0
SI or I/O7 - I/O0
(INPUT)
CMD PA12-5 PA4-0, BA10-8 BA7-0 X X
CS
n n+1 SO or I/O7 - I/O0
(OUTPUT)
SI or I/O7 - I/O0
(INPUT)
CMD PA12-5 PA4-0, XXX X
Starts reading page data into buffer
CS
SO or I/O7 - I/O0
(OUTPUT)
SI or I/O7 - I/O0
(INPUT)
CMD X BFA10-8 BFA7-0
CS
n n+1 SO or I/O7 - I/O0
(OUTPUT)
X
Each transition
represents 8 bits
n = 1st byte read
n+1 = 2nd byte read