S25FL004A Meet Spansion Inc., S25FL004A Datasheet - Page 17

• Manufacturer Part Number: S25FL004A
• Description: 4-megabit Cmos 3.0 Volt Flash Memory With 50 Mhz Spi Bus Interface
• Manufacturer: Meet Spansion Inc.

9.4
July 9, 2007 S25FL004A_00_B3
Write Enable (WREN)
The Write Enable (WREN) command (see
enables the device to accept a Write Status Register, program, or erase command. The WEL bit must be set
prior to every Page Program (PP), Erase (SE or BE) and Write Status Register (WRSR) command.
The host system must first drive CS# low, write the WREN command, and then drive CS# high.
CS#
SCK
SI
SO
Mode 3
Mode 0
Hi-Z
Figure 9.3 Read Identification (RDID) Command Sequence and Data-Out Sequence
Manufacturer Identification
0
1
01h
D a t a
Table 9.1 Read Identification (RDID) Data-Out Sequence
CS#
2
SCK
SO
SI
Figure 9.4 Write Enable (WREN) Command Sequence
Command
3
4
Mode 3
Mode 0
Hi-Z
S h e e t
5
6
S25FL004A
Figure
7
0 1
MSB
8
Manufacturer Identification
9.4) sets the Write Enable Latch (WEL) bit to a 1, which
9
2 3
Command
10 11 12
4 5 6 7
Memory Type
02h
13
14 15 16
Device Identification
15
Device Identification
14
17 18
13
Memory Capacity
3
28 29 30 31
2
12h
1
0
17