S29PL-N_07 SPANSION [SPANSION], S29PL-N_07 Datasheet - Page 27

• Manufacturer Part Number: S29PL-N_07
• Description: 256/128/128 Mb (16/8/8 M x 16-Bit) CMOS, 3.0 Volt-only Simultaneous Read/Write, Page-Mode Flash Memory
• Manufacturer: SPANSION [SPANSION]

June 6, 2007 S29PL-N_00_A5
7.4.2
Write Buffer Programming
Write Buffer Programming allows the system to write a maximum of 32 words in one programming operation.
This results in a faster effective word programming time than the standard word programming algorithms. The
Write Buffer Programming command sequence is initiated by first writing two unlock cycles. This is followed
by a third write cycle containing the Write Buffer Load command written at the Sector Address in which
programming occurs. At this point, the system writes the number of word locations minus 1 that is loaded into
the page buffer at the Sector Address in which programming occurs. This tells the device how many write
buffer addresses are loaded with data and therefore when to expect the Program Buffer to Flash confirm
command. The number of locations to program cannot exceed the size of the write buffer or the operation
aborts. (Number loaded = the number of locations to program minus 1. For example, if the system programs
6 address locations, then 05h should be written to the device.)
The system then writes the starting address/data combination. This starting address is the first address/data
pair to be programmed, and selects the write-buffer-page address. All subsequent address/data pairs must
fall within the elected-write-buffer-page.
The write-buffer-page is selected by using the addresses A
The write-buffer-page addresses must be the same for all address/data pairs loaded into the write buffer.
(This means Write Buffer Programming cannot be performed across multiple write-buffer-page. This also
means that Write Buffer Programming cannot be performed across multiple sectors. If the system attempts to
load programming data outside of the selected write-buffer-page, the operation
After writing the Starting Address/Data pair, the system then writes the remaining address/data pairs into the
write buffer.
Note that if a Write Buffer address location is loaded multiple times, the address/data pair counter
decrements for every data load operation. Also, the last data loaded at a location before the Program Buffer
to Flash confirm command is programmed into the device. The software takes care of the ramifications of
loading a write-buffer location more than once. The counter decrements for each data load operation,
each unique write-buffer-address location. Once the specified number of write buffer locations have been
loaded, the system must then write the Program Buffer to Flash command at the Sector Address. Any other
address/data write combinations abort the Write Buffer Programming operation. The device then goes busy.
The Data Bar polling techniques should be used while monitoring the last address location loaded into the
write buffer. This eliminates the need to store an address in memory because the system can load the last
address location, issue the program confirm command at the last loaded address location, and then data bar
poll at that same address.
The write-buffer embedded programming operation can be suspended using the standard suspend/resume
commands. Upon successful completion of the Write Buffer Programming operation, the device returns to
READ mode.
If the write buffer command sequence is entered incorrectly the device enters write buffer abort. When an
abort occurs the write-to buffer-abort reset command must be issued to return the device to read mode.
The Write Buffer Programming Sequence is
Use of the write buffer is strongly recommended for programming when multiple words are to be
programmed. Write buffer programming is approximately four times faster than programming one word at a
time. Note that the Secured Silicon, the CFI functions, and the Autoselect Codes are not available for read
when a write buffer programming operation is in progress.
Load a value that is greater than the page buffer size during the Number of Locations to Program step.
Write to an address in a sector different than the one specified during the Write-Buffer-Load command.
Write an Address/Data pair to a different write-buffer-page than the one selected by the Starting Address
during the write buffer data loading stage of the operation.
Write data other than the Confirm Command after the specified number of data load cycles.
D a t a
S h e e t
S29PL-N MirrorBit
( P r e l i m i n a r y )
ABORTED
™
Flash Family
under any of the following conditions:
max
– A5.
ABORTS
.)
NOT
for
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