S25FL008A Meet Spansion Inc., S25FL008A Datasheet - Page 15

• Manufacturer Part Number: S25FL008A
• Description: 8-megabit Cmos 3.0 Volt Flash Memory With 50 Mhz Spi Bus Interface
• Manufacturer: Meet Spansion Inc.

9.2
9.3
June 29, 2007 S25FL008A_00_B2
Read Data Bytes at Higher Speed (FAST_READ)
Read Identification (RDID)
The FAST_READ command reads data from the memory array at the frequency (f
input, with a maximum speed of 50 MHz. The host system must first select the device by driving CS# low. The
FAST_READ command is then written to SI, followed by a 3-byte address (A23-A0) and a dummy byte. Each
bit is latched on the rising edge of SCK. The memory array data, at that address, are output serially on SO at
a frequency f
The FAST_READ command sequence is shown in
specified can be at any location. The device automatically increments to the next higher address after each
byte of data is output. The entire memory array can therefore be read with a single FAST_READ command.
When the highest address is reached, the address counter reverts to 00000h, allowing the read sequence to
continue indefinitely.
The FAST_READ command is terminated by driving CS# high at any time during data output. The device
rejects any FAST_READ command issued while it is executing a program, erase, or Write Status Register
operation, and continues the operation uninterrupted.
The Read Identification (RDID) command outputs the one-byte manufacturer identification, followed by the
two-byte device identification, to the host system.
JEDEC assigns the manufacturer identification byte; for Spansion devices it is 01h. The device manufacturer
assigns the device identification: the first byte provides the memory type; the second byte indicates the
memory capacity. See
The host system must first select the device by driving CS# low. The RDID command is then written to SI,
and each bit is latched on the rising edge of SCK. The 24-bit device identification data is output from the
memory array on SO at a frequency f
The RDID command sequence is shown in
Driving CS# high after the device identification data has been read at least once terminates the READ_ID
command. Driving CS# high at any time during data output also terminates the RDID operation.
The device rejects any RDID command issued while it is executing a program, erase, or Write Status Register
operation, and continues the operation uninterrupted.
SCK
SO
CS#
SI
Mode 3
Mode 0
Hi-Z
Figure 9.2 Read Data Bytes at Higher Speed (FAST_READ) Command Sequence
SCK
0
, on the falling edge of SCK.
1
2
Command
Table 9.1 on page 16
3
D a t a
4
5
6
7
23 22 21
S h e e t
8
SCK
9
24-Bit Address
S25FL008A
, on the falling edge of SCK.
10
Figure 9.3 on page 16
or
28 29 30
3
Table 9.4 on page 23
2
1
Figure 9.2
31 32 33
0
7
6
Dummy Byte
34 35 36 37 38
5
and
4
3
Table 9.4 on page
and
2
for device ID data.
1
Table 9.4 on page
39
0
MSB
7
40 41
6
5
42 43 44 45
DATA OUT 1
SCK
4
) presented at the SCK
23. The first byte
3
2
23.
1
46
0
47
MSB
7
DATA OUT 2
15