32Mb, 64Mb, 128Mb: 3V Embedded Parallel NOR Flash
Program Operations
mand requires two bus WRITE operations fewer than the standard WRITE TO BUFFER
PROGRAM command.
The UNLOCK BYPASS WRITE TO BUFFER PROGRAM command behaves the same way
as the WRITE TO BUFFER PROGRAM command: the operation cannot be aborted, and
a bus READ operation to the memory outputs the status register.
The WRITE TO BUFFER PROGRAM CONFIRM command is used to confirm an UN-
LOCK BYPASS WRITE TO BUFFER PROGRAM command and to program the n + 1
words/bytes loaded in the program buffer by this command.
ENHANCED WRITE TO BUFFER PROGRAM Command
The ENHANCED WRITE TO BUFFER PROGRAM (33h) command enables loading 256
words into the writer buffer to reduce system programming time. Each write buffer has
the same A[22:8] addresses. Execution speed is identical to the 256-word WRITE TO
BUFFER program speed (See the Program/Erase Characteristics table for details).
When issuing this command, the VPP/WP# pin can be held HIGH or raised to VPPH (pro-
gramming acceleration).
Note: The ENHANCED WRITE TO BUFFER PROGRAM command is available only in
the 128Mb x16 device,
The following successive steps are required to issue the command: Two unlock cycles
begin the command, followed by a third bus write cycle that sets up the command with
setup code that can be addressed to any location within the targeted block. The fourth
bus write cycle loads the first address and data to be programmed. There are a total of
256 address and data loading cycles.
The command must be followed by an ENHANCED WRITE TO BUFFER PROGRAM
CONFIRM command to program the buffer content, which confirm cycle ends the
command.
Note that address/data cycles must be loaded in an increasing address order (A[7:0]
from 00h to FFh) that includes all 256 words. Invalid address combinations or the cor-
rect sequence of bus write cycles will result in an abort.
Status register bits DQ1, DQ5, DQ6, and DQ7 enable monitoring the device status dur-
ing operation. A 12V external supply can be used to improve programming efficiency.
The ENHANCED WRITE TO BUFFER PROGRAM command should not be used to
change a bit set to 0 back to 1. Any attempt to do so is masked during the operation. The
ERASE command should be used to set memory bits from 0 to 1.
UNLOCK BYPASS ENHANCED WRITE TO BUFFER PROGRAM Command
The UNLOCK BYPASS ENHANCED WRITE TO BUFFER PROGRAM (33h)command can
be used to program the memory in fast program mode. The command requires two ad-
dress/data loading cycles less than the regular ENHANCED WRITE TO BUFFER PRO-
GRAM command. This command behaves identically to the ENHANCED WRITE TO
BUFFER PROGRAM command. The operation cannot be aborted and a bus read opera-
tion to the memory outputs the status register. This command is confirmed by the EN-
HANCED WRITE TO BUFFER PROGRAM CONFIRM command, which programs the
256 words loaded in the buffer.
PDF: 09005aef84dc44a7
m29ew_32Mb-128Mb.pdf - Rev. B 11/12 EN
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