S29GL128P90TFCR20 Spansion Inc., S29GL128P90TFCR20 Datasheet - Page 24

• Manufacturer Part Number: S29GL128P90TFCR20
• Description: IC 128M PAGE-MODE FLASH MEMORY
• Manufacturer: Spansion Inc.

7.7
24
7.7.1
Program/Erase Operations
Single Word Programming
These devices are capable of several modes of programming and or erase operations which are described in
detail in the following sections.
During a write operation, the system must drive CE# and WE# to V
command, and data. Addresses are latched on the last falling edge of WE# or CE#, while data is latched on
the 1st rising edge of WE# or CE#.
The Unlock Bypass feature allows the host system to send program commands to the Flash device without
first writing unlock cycles within the command sequence. See
function.
Note the following:
 When the Embedded Program algorithm is complete, the device returns to the read mode.
 The system can determine the status of the program operation by reading the DQ status bits. Refer to the
 An “0” cannot be programmed back to a “1.” A succeeding read shows that the data is still “0.”
 Only erase operations can convert a “0” to a “1.”
 Any commands written to the device during the Embedded Program/Erase are ignored except the
 Secured Silicon Sector, Autoselect, and CFI functions are unavailable when a program operation is in
 A hardware reset and/or power removal immediately terminates the Program/Erase operation and the
 Programming is allowed in any sequence and across sector boundaries for single word programming
 Programming to the same word address multiple times without intervening erases is permitted.
Single word programming mode is one method of programming the Flash. In this mode, four Flash command
write cycles are used to program an individual Flash address. The data for this programming operation could
be 8 or 16-bits wide.
While the single word programming method is supported by most Spansion devices, in general Single Word
Programming is not recommended for devices that support Write Buffer Programming. See
on page 69
When the Embedded Program algorithm is complete, the device then returns to the read mode and
addresses are no longer latched. The system can determine the status of the program operation by reading
the DQ status bits. Refer to
 During programming, any command (except the Suspend Program command) is ignored.
 The Secured Silicon Sector, Autoselect, and CFI functions are unavailable when a program operation is in
 A hardware reset immediately terminates the program operation. The program command sequence should
 Programming to the same address multiple times continuously (for example, “walking” a bit within a word)
Write Operation Status on page 36
Suspend commands.
progress.
Program/Erase command sequence should be reinitiated once the device has returned to the read mode
to ensure data integrity.
operation. See
progress.
be reinitiated once the device has returned to the read mode, to ensure data integrity.
is permitted.
for the required bus cycles and
Write Buffer Programming on page 26
Write Operation Status on page 36
S29GL-P MirrorBit
for information on these status bits.
Figure 7.1
D a t a
®
Flash Family
for the flowchart.
S h e e t
when using the write buffer.
Section 7.7.8
for information on these status bits.
IL
and OE# to V
S29GL-P_00_A13 November 17, 2010
for details on the Unlock Bypass
IH
when providing address,
Table 12.1