at45db021d-ssh-sl955 ATMEL Corporation, at45db021d-ssh-sl955 Datasheet - Page 40

• Manufacturer Part Number: at45db021d-ssh-sl955
• Description: 2-megabit 2.7-volt Minimum Dataflash
• Manufacturer: ATMEL Corporation

23. Read Operations
The following block diagram and waveforms illustrate the various read sequences available.
23.1
23.2
40
SO (OUTPUT)
Main Memory Page Read
Main Memory Page to Buffer Transfer (Data from Flash Page Read into Buffer)
SI (INPUT)
AT45DB021D
SO (OUTPUT)
SI (INPUT)
CS
CS
MAIN MEMORY
PAGE (256/264 BYTES)
BUFFER (256/264 BYTES)
PAGE TO
BUFFER
BUFFER
CMD
READ
ADDRESS FOR BINARY PAGE SIZE
CMD
A17-A16
PA9-7
FLASH MEMORY ARRAY
PA6-0, BA8
A15-A8
I/O INTERFACE
6 DON’T CARE BITS + A17-A8 + 8 DON'T CARE BITS
X···X, PA9-7
SO
A7-A0
BA7-0
MAIN MEMORY
PAGE READ
BINARY PAGE SIZE
X
4 Dummy Bytes
PA6-0, X
Starts reading page data into buffer
X
XXXX XXXX
n
n+1
3638F–DFLASH–4/08